REPRODUCTIVE AND DEVELOPMENTAL BIOLOGY OF CHELINIDEA VITTIGER t'HLER
(HEMIPTERA: COHEIDAE)
by STANLEY CLAY CARROLL, B.S.
A THESIS IN ENTOMOLOGY
Submitted to the Graduate Faculty of Texas Tech University in Partial Fulfillment of the Reauirements for the Degree of MASTER OF SCIENCE
Approved
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AC~~OWLEDG1'IENTS
Special appreciation is extended to Dr. James K.
Wangberg for his encouragement, direction, and guidance as the chai~~an of my committee. Dr. Darryl P. Sanders and
Dr. Joe R. Goodin are also extended my appreciation for the suggestio~s and constructive criticism during the development and completion of my graduate studies. Sincere thanks also go out to Dr. David E. Foster, former Texas Tech professor, for his guidance at the initiation of this study.
My wife, Cheryl, is also thanked for her patience and assis- tance in preparing my thesis.
This study was conducted through the facilities and financial resources provided by Texas Tech University. To this institution I am indebted.
ii TABLE OF CONTENTS
ACK1~0WLEDG11ENTS ...... i i
LIST OF TABLES ...... i v
LIST 0 F FIGURES ...... v
LIST OF APPENDICES ...... vi
I . INTRODUCTION...... 1
Review of Lit era ture...... 5
I I . METHODS AND \lATER I ALS ...... 16
Laboratory Colonization of Chelinidea vittiger ...... 16
Rearing Techniques for Data Collection ...... 18
III. RESULTS ru~D INTERPRETATIONS ...... 26
Temperature Effects on Nymphal Development ...... 26
Staggered Nymphal Development ...... 32
P reov1pos. 1•t• 1on...... 3°...;
Reproduction Potential ...... 36
Adult Longevity ...... 44
IV. SUMMARY AND CONCLUSIONS ...... 45
LITERATURE CITED ...... 48
.APPEi\TD I CE S ...... 50
iii LIST OF TABLES
1. Duration (Days) of the various life stages of Chelinidea vittiger as reported by previous researchers ...... 13
2. Percentage of Chelinidea vittiger nymphs dying in each life stage whe~ reared at six constant temperatures (Based upon the most advanced stage reached by each nymph). Lubbock, Texas, 1978-79: ...... 27
3. Relative humidity ranges recorded for the six temperature treatmen~s. The ranges are based on the lowest and highest relative humidity readings and also the most common range observed. Lubbock, Texas} 1978-79 ...... 28
4. Developmental time requirements for those 1st instar Chelinide~ vittlger nyTiphs reaching the adult stage when reared at three constan~ temperatures. Lubbock, Texa.s, 1978-79 ...... 31
5. Preoviposition requirements for Chelinidea vittiger when reared at three constan~ temperat1rres. Lubbock, Texas, 1978-79 ...... 34
iv LIST OF FIGURES
1. Life stages of Chelinidea vittiger (left to right: adult, third instar nymph, eggs) ...... 2
2. Heavy infestation of Opuntia in the Rolling Plains of Texas...... 2
3. Chlorotic lesions; the initial symptom caused by the feeding activity of Chelinidea vittiger ...... 10
~- Vinyl plastic cage and enclosed prickly pear cactus plant utilized in rearing Chelinidea vittiger ...... 19 o. Mean number of eggs produced per week by the ovipositing Chelinidea vittiger females caged at three constant temperatures for the initial fourteen weeks of the adult stage. Weekly means based on the number of ovipositing females living at each inspection. Lubbock, Texas, 1978-79 ...... 39
6. Mean number of eggs produced per week by Chelinidea vittiger females (both ovipositing and non-ovipositing) caged at three constant temperatures for the initial fourteen weeks of the adult stage. Weekly means based on the total number of females living at each inspection. Lubbock, Texas, 1978-~9 ...... 40
7. Cumulative mean number of eggs produced by the ovipositing Chelinidea vittiger females caged at three constant temperatures for the initial fourteen weeks of the adult stage (after Lublinkhof 1976). Lubbock, Texas, 1978-79 ...... 42
8. Cumulative mean number of eggs produced by Chelinidea vittiger females (both ovipositing and non-ovipositing) caged at three constant temperatures for the initial fourteen weeks of the adult stage (after Lublinkhof 1976). Lubbock, Texas, 1978-79 ...... 43
v LIST OF APPENDICES
A. Developmental data for the nymphs of Chelinidea vittiger reared at six constant temperatures. Lubbock, Texas, 1978-79 ...... 51
B. Chi-Square analysis of the Chelinidea vittiger nymphs reaching the adult stage when reared at six constant temperatures. Lubbock, Texas, 1978-79 ...... 57
c. Analysis of variance and Duncan's multiple range test for the time Chelinidea vittiger nymphs require to reach the adult stage when reared at three constant temperatures. Lubbock, Texas, 1978-79 ...... 58
D. Nymphal development of Chelinidea vittiger nymphs reared under similar environmental conditions. The nymphs originated from seven pairs of adults producing eggs at 31°C. Lubbock, Texas, 1979 ...... 59
E. Analysis of variance for the immature develop ment of Chelinidea vittiger. Analysis is based upon the egg incubation and nymphal development periods combined for 24 nymphs originating from four pairs of adults. Lubbock, Texas, 1979 ...... 62
F. Analysis of variance for the comparison of the i~~ature development of the males versus females of Chelinidea vittiger. Analysis is based upon the combined egg incubation and nymphal development periods for eight females and thirteen males reared under similar environ- mental conditions. Lubbock, Texas, 1979 ...... 63
G. Analysis of variance and Duncan's multiple range test for the preoviposition time require ments of Chelinidea vittiger females producing eggs when reared at three constant temperatures. Lubbock, Texas, 1978-79 ...... 64
H. Reproductive behavioral responses of ~_e_l_i_n_l_·d__ e_a vittiger females reared at six constant temp- eratures. Lubbock, Texas, 1978-79 ...... 65
vi Appendix
J. Chi-Square analysis for egg production of Chelinidea vittiger females reared at six constant temperatures. Lubbock, Texas, 1978-79 ...... -71
J. Analysis of variance and Duncan's multiple range test for the reproductive potential of Chelinidea vittiger females producing eggs when reared at three constant temperatures. Analysis is based upon the mean number of eggs produced per week over the lifetime of each female but excluding the preoviposition period. Lubbock, Texas, 1978-79 ...... 72
K. Egg production in the initial 14 weeks of the adult stage for Chelinidea vittiger females reared at six constant temperatures. Lubbock, Texas, 1978-79 ...... 7 ~
L. Longevity of the adult stage in Chelinidea vittiger females and males when reared at six constant temperatures. Lubbock, Texas, 1978-79 ...... 78
vii CHAPTER I
INTRODUCTION
Chelinidea vittiger Uhler, one of four species collec tively known as the cactus bugs, is documented as one of the most important of the native enemies of prickly pear (Fig ure 1). Hunter et al. (1912) concluded in their study of the insects affecting cactus that the cactus bugs are by far the most important native enemy of prickly pear cactus
(Opuntia spp.) found in the United States. This decision was based upon the prolific breeding and the wide distribu tion of C. vittiger in the United States.
This cactus bug attacks most, if not all, species of prickly pear cactus within tts range of distribution (Mann
1969). It is reported to be found in essentially all regions of the prickly pear distribution, extending from the Atlantic coast across to the Pacific coast and into northern ~exico
(Dodd 1940, Mann 1969).
Prickly pear infests millions of acres of rangeland often unchecked by other less competitive range plant species
(Figure 2). Although many control methods have been inves tigated for prickly pear cactus, biological control is often the only feasible approach. Prickly pear species often
1 2
.Figure 1. Life stages of Chelinidea vittiger (left to right; adult, third instar nymph, eggs).
Figure 2. He.:-avy infestation of _9pu~t . \i~~ ~r~ the Rolli.ng n-- .· · · f ,.., ..: .L~.J.l1!-> o. _ exas. 3
invade relatively inferior land, and the low-value-per-acre
of the rangeland prohibits the use of other control methods.
Due to the permanent nature of the control, biological
control programs utilizing insect species have already proved
successful in suppressing prickly pear infestations at a
relatively low cost.
In recent months there has been a renewed interest i~
a possible biological control program against prickly pear
in the southern areas of the United States. Since Opuntia
species serve some regions as a valuable forage for livestock
in periods of drought and also as a source of human food,
the cactus is not considered to be a pest in some areas. If
a conflict of interest exists, it might be necessary to uti
lize indigenous arthropod species instead of inGroducing
exotic species. Understanding the life histories of the
indigenous insects such as C. vittiger is an important ele ment in the establishment of future biological control pro-
grams.
Several aspects of C. vittiger's biology have been noted t~at point toward its potential as a biological control agent. T~J.e grega::-ious nature of the nymphs and adults leads to a more concentrated attack against the host plant (Mann
1969). Its wide distribution in the United States and extensive host range within the genus Opuntia suggests C. vittiger may adapt easily to a variety of environmental 4 conditions. Although never confirmed, this cactus bug may be a vector of numerous fungal pathogens which promote decay of the plant tissue (Hewitt et al. 1974).
The literature suggests one disadvantage ln the use of
C. vittiger as a biocontrol agent. Hamlin (1924) and others noted the reluctance of cactus bugs to fly or migrate to new areas. They suggest that evolution of cactus insects with a host affording such a high degree of protection may be responsible for the sluggish nature.
Previous biological control programs in Australia and
Santa Cruz Island, California have contributed greatly to the existing literature on the biology of this cactus bug.
Field observations and rearing attempts from these control programs have provided impor~ant information on nymphal development and reproduction. This study was designed to establish the effects of temperature upon the nymphal devel opment and reproduction of C. vittiger. The major objectives were as follows:
1. To evaluate the effect of temperature upon
the nymphal development of C. vittiger,
2. To investigate and theorize the cause for
the unexplained staggered development of
the nymphs of C. vittiger, and
3. To evaluate the effect of tempera~ure upon the reproductive potential of the females
of C. vittiger.
Although temperature is only one variable affecting establishment, development, and reproduction of this insect species, the study could be instrumental in predicting the potential of this species as a biological control agent in
a specific region. The study presents data which could supplement future studies in the development of life tables
for C. vittiger.
Review of Literature
Since 1912 a limited number of researchers have inves-
tigated the life histories of arthropods which damage prickly pear cactus. The investigations resulted in several excel-
lent reviews presenting biological data on C. vittiger
(Hunter et al. 1912, Hamlin 1924, Dodd 1940, Goeden et al. -- - 1967 and Mann 1969). The following discussion summarizes the curren~ literature on the biology of C. vittiger with emphasis on those aspects pertinent to its reproductive and developmental biology.
Host Plant
Pri~kly pear cactus is native to the Western Hemisphere.
~ost prickly oear species belong to the subgenus Phatyouuntia or flat-segment section of the genus Opuntia (Dodd 1940). 6
A few species are found in a closely related genus, Nopalea.
Prickly pear is a very competitive plant in comparison to most range species. Poor range management is probably the major cause of extensive prickly pear populations
(Goeden et al. 1967, Schaffner 1938). Outside the Western
Hemisphere, i~troduced prickly pear species established readily because most of the native enemies were not carried into new areas along with the host plant (Yann 1969). Dodd
(1940) gives three reasons for the establis~~ent of prickly pear in areas outside the Western Hemisphere: 1) cultivation of prickly pear as a food source for the dye-producing cochineal insects, 2) cultivation of the fruit for human food, and 3) cultivation as an ornamental.
Systematics
Chelinidea vittiger was described by Uhler in 1863. He established the genus based upon specimens collected in Utah and Montana which he described as C. vittiger (Hamlin 1924).
Four species now comprise the genus of cactus bugs within the hemipteran family Coreidae.
McAtee (1919) and Hamlin (1924) chose to divide C. vittiger into two subspecies. The subspecies level is based on the degree of carination of the pronotum and the oromi nence of the anterior, lateral pronotal tubercles. These researchers have noted a color variety within each of the subspecies. In Texas, two color varieties exist with the 7 differences more noticeable in the nymphs. Some nymphs have a pea-green colored abdomen while others have abdomens of dark crimson. Hunter et al. (1912) repeatedly cross-bred the adults of the two color varieties and reported that the resulting adults could not be distinguished.
General Biology
Slater and Baranowski (1978) describe the distribution of C. vittiger as occurring throughout the southern United
States from Virginia to Florida and across to California in locations where prickly pear cactus occurs. The southern limits of C. vittiger extend into the northern states of
Mexico and the.northern limits extend as far north as Wyoming and Idaho (Hunter et al. 1912).
Chelinidea vittiger passes the winter in the adult stage. During the quiescent period the adults usually cluster together under prickly pear pads that are lying flat against the soil surface or in the debris surrounding the prickly pear plant (Hamlin 1924, Hunter et al. 1912).
Mann (1969) explains that the dormancy is not complete since the bugs often emerge from the overwintering site and feed on warm winter days. ~ann noted at the higher elevations and colder latitudes that C. vittiger may be in a quiescent state for two or three months.
Both the ~ymphs and the adults of C. vittiger are gregarious on the host plant. The adults are slightly less 8 gregarious except during the overwintering period (Hamlin
1924). Chelinidea vittiger is primarily nocturnal in its habits according to Hunter et al. (1912). Chelinidea vittiger produces two generations per year
(Alexander 1925, Mann 1969). Hunter et al. (1912) report the adults mate numerous times throughout the summer and fall.
The females of C. vittiger normally attach the eggs linearly to the underside of the cactus spines (Hewitt et al.
19 74). Goeden et al. (1967) state that 3-16 eggs per mass are attached to each spine. The females occasionally attach the eggs to the plant surface, ajacent plants, or the sides of rearing cages. Eggs deposited early in the spring by the overwintered adults hatch after approximately twelve days
(Mann 1969). The nymphs pass through five instars. First generation adults appear from about May to July (Mann 1969).
Hamlin (1924) indicates that the first generation adults are initially heavy feeders. Mating and reproductive activities are more noticeable in older individuals. These adults oviposit from July to November and the second genera- tion adults represent the usual overwintering stage. Ovi- position is delayed until the following spring (~ann 1969).
Chelinidea vittiger is dependant on species of Cactaceae to complete its life cycle. Hewitt --et al. (1974) state C. vittiger feeds on the sap and sometimes the fruit of many species of prickly pear cactus. Hamlin (1924) reports 9
C. vittiger nymphs and adults feed upon the various Opuntia species, tasajillo (Opuntia leptocaulis De Candolla), and
Echinocereus species. Chelinidea vittiger is rarely found on the cylindical forms (Cylindropuntia) of Opuntia while a definite host preference exists for the Phatyopuntia (prickly pear).
The feeding activity by nymphs and adults of C. vittiger produces chlorotic lesions, necrotic plant tissue, structural weakening, pad abscission and occasional death of the plant
(Hamlin 1924, Goeden et al. 1967) (Figure 3). Hunter et al.
(1912) and Hamlin (1924) suggest a significant amount of indirect damage, occurs due to increased winter frost damage occurring on plants damaged by the cactus bugs. Growth of the plant is also retarded due to preferred feeding on new growth and flower buds as they sprout from the Joints. Mann
(1969) theorizes that the cactus bug!s greatest contribution to prickly pear control is the prevention of growth and fruiting rather than the destruction of joints and plants.
Hunter et al. (1912) and others (Hamlin 1924, Dodd 1940,
Mann 1969, and Hewitt et al. 1974) theorize C. vittiger is a vector of fungal pathogens which are detrimental to prickly pear cactus. The fungal spores are believed to be trans- mitted on the beaks of the bugs (Hamlin 1924). The feeding punctures serve as an entry site into the plant. 10
Figure 3. Chlorotic lesions; the initial symptom caused by the feeding activity of ~helinidea vittiger. 11
Additional studies have included starvation tests to determine the potential damage to other plant genera (Dodd
1940, Fullaway 1954). These host limitation tests have been conducted on C. vi~tiger to insure the safety of importing the insect to new areas. In the host limitation tests conducted for the Australia prickly pear control program, C. vittiger was capable of producing feeding scars on torna:o fruit as nymphs and various other fruit plants as adults (Dodd 1940). The researchers concluded that the nymphs lived a very short time on alternate hosts and the life cycle could not be completed without Opuntia. Authori- ties felt there was no danger to economic plants and authorization was given to release C. vittiger into Australia.
Chelinidea vittiger produced feeding scars on pineapple plants in host limitation tests for the control program in
Hawaii (Fullaway 1954). Due to the economic importance of pineapple in Hawaii, C. vittiger was rejected for release into Hawaii.
Hamlin (1924) reported several parasites and predators of C. vittiger. A tachinid parasite, Trichopoda pennipes
Fabricius was found to be a common parasite of C. vi~tiger. ' - An egg parasite, Hadronotus sp., was reared from C. vittiger eggs at Uvalde, Texas. Another insect, Y.onomorium minimum
Buckley, was observed preying on the eggs at Uvalde. Hamlin also noted two spiders, Phidippus workm~ni Peckman and 12
Phidippus £alifornicus Peckham, to be common predators to the nymphs of C. vittiger.
Nymphal Development
In the past, researchers have carefully observed the time requirements for incubation and nymphal development of
C. vittiger. Their published records hc<-Ve been summarized in Table 1.
Previous researchers recognized the effect that temperature has upon the incubation and developmental time requirements of C. vittiger. Hamlin (1924) recorded the duration for tne fourth and fifth instars during September and early October and theorized that these st~di~ would be much shorter in the summer than at other times. Similar speculations were made by Hunter et al. ( 1912) and ~fann
(1969). Attempts have not been made to study nymphal development under controlled temperatures.
An unexplained phenomenon regarding the nymphal development of C. vittiger has been observed by numerous researchers. A staggered rate of nymphal development, even under indentical conditions, has besn observed (Hamlin 1924,
Hunter et al. 1912 and j1ann 1969). Hunter et al. ( 1912) reported that some nymphs from the same female reached the adult stage while others had not completed the third instar.
The staggered r~te of nymphal development is more pronounced in the autumn men ths ( Jclann 1.969) . 13
Table 1. Duration (Days) of the various life sta~es of Chelinidea vitti~er as reported by previous ------researchers. r-1 r;:; r-< +..) s:: ~ h h h h. r:.:.. c: (1) -' ~ :.,_, 0 ro ..; d d cj (1) .,...j ,.-- ~ ~ ~ ..r--> > . c •r-1 +-> ,__, r- .., ..w [/) ~ rn rn en rn...... ?-...... ,....., ~'"d ..... ,.... s:: c c: ~- ...... 0 H H H H- H ,...... ~-- ,....; lJ ~-~ ,.) (1) ro ,....; ~ ...... -- ~ (.) v +-> .._; "0 ..c ..c +..l,....., > (1) .,._, (J -..; s:: en c: ::-. +.> '-' ,-., ·"" ~ H -~. C'f:) ~ '1'"1 LD ~ ~ u Literature . C\l ~ E--.
Hunter et al. (1912) 12-20 7 4 4 12 14 41
Hamlin (1924) 9-12 7 7 15 18 53
Goeden et al. (1967) 12-20
Mann (1969)a/ 53-73
· Mann (1969)b/ 12 8-11 7-9 11-14 13-15 15-18 54-67 66-79
Hewitt et al. (1974) 9-20
~/ Nymphal development of C. vitti~er recorded in October and November in Australia.
b/ ~ymphal development of C. vittiger recorded from January to ~arch in Australia. 14
The unequal rate of nymphal development, in addition to long-lived females producing eggs over a two or three month period, is responsible for early researchers being confused about the number of generations produced per year
(Mann 1969). Hamlin (1924) estimated that four to five generations were produced per year. Hunter et al. (1912) declined to even estimate the number of generations produced.
Alexander (1925) studied C. vittiger closely and determined there were actually two generations per year.
Reproductive Potential
Preoviposition periods are not specifically discussed in the literature. Since the adults of the second genera- tion do not oviposit un~il the following spring (Hunter et al. 1912), it can be assumed that under field conditions the preoviposition period extends from the late fall until the following spring. The first generation bugs reach the adult stage in May to July and oviposit from July TO ~ov- ember. This observation would indicate that the preovipo- sition period could be from four to twelve weeks.
The number of eggs deposited has been documented by
Hunter et al. (1912). They observed that five females produced 198 eggs in a fifteen day period. This observation represents an average of 40 eggs per female. The test was not continued, but the authors stated the egg-laying capac- ity is most likely much longer than these observations 15 indicate. Mann (1969) noted a record number of 230 eggs oviposited by a second generation female utilized in the
Australia program. The female produced numerous eggs in
October and November and a few eggs in February and March.
Adults of the second generation are not reported to produce eggs until the following spring. Therefore, it is beli.eved this female must have been reared at a relatively high temperature or observed in Australia where it was subject to different seasonal patterns. Another female produced
220 eggs in 27 separate egg masses within a two month period.
Eggs will be produced over a period of several weeks accord ing to Hamlin (1924). Mann (1969) reports the overwintering females, as a group, oviposit for a three month period in the early spring. The first generation females, as a group, produce eggs from July to November.
The observations by Mann (1969) suggest an extended longevity of the adults of C. vittiger. The same female which produced the 230 eggs survived 542 days. CHAPTER II
METHODS AND ~IATERIALS
Laboratory Colonization of Chelinidea vittiger
A laboratory colony of C. vittiger was established for
this research program in the insectary of the Texas Tech
University Department of Entomology. The colony provided
first instar nymphs and newly emerged adults for the experi ments at times when it would have been impossible or diffi
cult to locate these life stages in the field. Although numerous techniques were utilized in the development of a , colony, only the most advantageous modifications will be discussed.
The colony was initiated and maintained with field collected C. vittiger nymphs and adults. The collections were made from January, 1978, until May of 1979, on the
Sneed Ranch located 20 miles (32 km) southeast of D~~as,
Texas (Moore County). The ranch had an adequate amount of prickly pear with an accessible population of C. vittiger at all ti~es of the year. The primary host of C. vittiger on the Sneed Ranch is Opuntia polyacantha Haworth.
Tbe colony was maintained on propagated prickly pear plants. Plant material utilized for propagation was obtained by cutting segmenGS, or pads, from plants located
16 17 on the Sneed Ranch. Potting entire plants tended to result in inferior quality plants, large amounts of accompanying debris, and the introduction of other cactus infesting arthropods into the laboratory.
Procedures presented by Shreve (1931) were utilized in propagating the cactus. Stems consisting from 1-4 pads were selected for good color, sturdy structure, and the absence of disease and insect damage. These plants were planted upright in three-liter (15 x 17 em) plastic pots. Approxi- mately one-half of the length was placed into the potting soil. The pot~ing soil was formed by mixing two-parts field collected sandy loam soil and one-part VermiculiteQD. The resulting mixture allowed the small volume of soil to ~old an adequate amount of water yet have a loose texture. Due to problems with root rot, I suggest the use of sterilized soil in any future rearing attempts.
The plants were watered approximately every ten days.
Watering the cactus numerous times with water containing high amounts of dissolved salts resulted in an accumulation of salts on the soil surface. Distilled water was used to eliminate insect mortality due to the salts. Increased sand content of the soil and higher volumes of water might also lower the salt accumulation.
The insectary was maintained at a variety of environ- mental conditions. A hygro-thermograph recorded the 18
temperature in the insectary which varied from 24° to 35°C.
Depending upon the temperature and the amount of water uTilized, the relative humidity varied from 35-75%. The
insecTary was programed for a 15-hr. photoperiod with
I fluorescent gro-light lamp banks.
The nymphs and adults were released onto the plants withouT any cages to confine the insects. The uncaged plants resulted in decreased costs, easy access to the bugs, ease in working with the plants, and allowed the bugs to move to undamaged plants for a new food source.
Rearing Techniques for Data Collection
The following section will present information on the method of caging C. vittiger which was utilized in three experiments dealing with nymphal development and reproductive biology. A separate discussion on each experiment will then complete this chapter.
Experimental Caging of Chelinidea vittiger
A method of caging C. vitTiger was adopted that allowed efficient handling of the insects, easy visual observation, minimum number of escapes, adequate light penetration for the plant, and easy care of the cactus plant (Figure 4).
Plants of 1-4 pads were propagated in three-liter pots as described in the section on laboratory colonization. The only variation was the addition of a 3-5 em layer of sand 19
Figure 4. Vinyl plastic cage and enclosed prickly pear cactus plant utilized in rearing Chelinidea vittiger. 20
to the surface of the potting soil to avoid an accumulation of salts on the soil surface. A cylinder of clear vinyl plastic sheeting, approximately 25 em tall, was pushed slightly into the soil surface around the inside edge of each pot. A 20 x 20 em sheet of fine mesh cloth covered the top end of the cylinder. Rubber bands secured the netting around the cage. The netting provided an opening for the removal and replacement of the bugs and a convenient site for watering the plant without removal of the cylinder.
The caged plants within each experiment were watered varying amounts depending upon the temperature and relati .....:e humidity. Plants were replaced as necessary to insure a good food source at all times.
Temperature Effects on ~~ymphal Development
Environmental chambers were programed at six tempera- ture levels; 1 0 0 , 170 , ~n40 , 310 , 380 , an d 4~0n~v ~._...... \ 15-hr. gro-light photoperiod was set for each treatment. Control over the relative humidity within the chambers was not possible. Hygro-thermographs were utilized periodically to record the relative humidity in each chamber.
To study the effect of temperature on nymphal devel- opment, newly hatched first instar nymphs were collected from the laboratory colony. The available nymphs were divided among the six treatments so that each treatment constantly possessed from five to ten nymphs. Each nymph 21
was placed on a separate plant. As nymphs reached the adult stage or died prior to the adult stage, they were replaced. An unequal number of replications were observed in the six treatments for two reasons. First, at the extreme low and high temperature treatments (10° and 45°C) a relatively small number of replications confir~ed the fact that nymphal development was greatly retarded or non- existent. These treatments were terminated after a pattern of retarded development was established so that the chambers could be programed for other treatments. Secondly, at some treatments development was accelerated so that replications required less time . • Weekly inspections were made to record the life stage
(instar) for each nymph (based upon a visual judgment).
Descriptions of the nymphal stages provided by Hunter et a~.
(1912) served as a guide for the life stage determinations.
The major characteristics utilized were color of the nymphs, relative size, and the presence of wing-pads in the later instars. When the adult stage was observed, the length of the nymphal stage was estimated by assuming that the nymph reached the adult stage the previous day. A similar un- biased assumption was made for those nymphs found dead.
The day prior to the inspection date was considered the last day the nymph was alive. 22
The experiment was based on a completely randomized design. An analysis of variance and Duncan's multiple range test yielded information on the rate of nymphal development between the six treatments. In addition, a
Chi-Square analysis was directed toward evaluatin~o differ- ences in the percentage of nymphs reaching t~e adult stage at the different temperature treatments.
Staggered Nymphal Development
The nymphal development of C. vittiger nymphs reared under similar environmental conditions was studied. Ny~phs from 382 eggs produced over a four month period by seven pairs of adults were utilized in this experiment. The eggs were produced by adults in the 31°C treatment of the repro- ductive potential experiment.
By transferring the paired adults onto fresh plants for short periods of time, plants could be collected with a small number of eggs of known age. Within three days after the eggs were produced, the plants were placed in a laboratory with a temperature of 25°C + 3°C and a relative humidity varying from 35-70%.
The egg incubation and nymphal development patterns were traced by weekly inspections. Data were collected on percent egg eclosion, number of nymphs located in each life stage (nymphal instar or adult stage), number of mortal- ities and the condition of the plant. Plants were wa~ered 23
or replaced as necessary to provide a good supply of fresh plant material.
Based upon the completely randomized design, an analy-
sis of variance of these data was performed to determine if
differences existed in the rate of development in nymphs
from different parent bugs. In addition, the rate of
development of males versus females was analyzed by an analysis of variance.
Preoviposition
Preoviposition periods were calculated for C. vittige~
females caged at the six temperatures noted earlier. The
preoviposition period for each ovipositing female was deter- mined as the number of weeks from initiation of the adult
stage until the weekly inspection in which eggs were first
observed. An analysis of variance (based on the completely
randomized design) and Duncan's multiple range test were
calculated to determine if the mean 9reoviposition periods
differed among the six temperature levels.
Reproductive Potential
To study the reproductive pote~tial of C. vittiger,
newly emerged females were individually caged with a male
on plan~s at each of the six prescribed temperature treat- ments. The environmental chambers programed for the SlX
temperature treatments (10 0 , 170 , 24 0 , 31 0 , 38 0 , and 45 0 C) 24
in the nymphal development experiment were also used for this reproductive biology experiment. The relative humidity ranges were also indentical to those in the nymphal develop ment experiment.
The females originated from late instar nymphs col lected from the laboratory colony. When available, field collected nymphs from near Dumas, Texas, supplemented the colony nymphs. ~ear the termination of the study a group of late instar nymphs were collected at a second location.
The nymphs were collected 10 miles (16 &~) southeast of
Jayton, Texas, in Stonewall County. Since different popu- lations of the same species could possibly respond differ- ently to the temperature treatments, adults originating from collections near Jayton, Texas, are labeled as such in the data.
Weekly records were made of the number of eggs pro- duced, distribution of eggs on the cactus spines, condition of the caged plants, and any other interesting aspects on the biology of C. vittiger. Newly hatched nymphs were removed to prevent excessive damage to ~he plants. Plants were reulaced as needed to insure a good food supply for ~ the adults.
The number of eggs produced per week by the females at each treatment served as an index of the reproductive potential. At the initiation of the study, egg eclosion 25
was considered as a possible estimate of the reproductive potential. This concept was soon abandoned when it was observed that environmental conditions within the treatments
(probably both temperature and humidity) greatly affected the fertility of the eggs. Egg counts served as a more reliable measurement of reproduction.
Differences in the percentage of ovipositing females at each treatment were analyzed with a Chi-Square analysis.
In addition, the mean number eggs produced per week at the treatments in which eggs were oviposited were calculated.
An analysis of variance and Duncan's multiple range test were utilized to establish differences in the reproductive potential of ovipositing females at each treatment.
Adult Longevity
The longevity of the adult stage was calculated, when possible, for the males and females in the reproductive potential experiment. Longevity was calculated as the number of days from the initiation of the adult stage ~ntil one day prior to the inspection in which the death of an adult was observed. CHAPTER III
P£SL~TS AND INTERPRETATIONS
Temperature Effects on Nymphal Development
The observed nymphal responses to six constant temp- erature treatme~ts are presented in Appendix A. These data reveal that many of the nymphs in all six treatments did not reach the adult stage. The percentage of the nymphs which reached each of the other life stages also varied within the different treatments (Table 2). The high mortality in the nymphal instars was probably due to three ' primary factors. They were: 1) the detrimental effects of laboratory rearing, 2) genetic characteristics, and 3) the detrimental effects of some temperature treatments (espe- cially the extreme low and high treatments). llortality due to the first cause was minimized by attempting to pro- vide laboratory conditions similar to field conditions.
Attempts were also made to create similar conditions at each treatment to prevent .a biased test. Secondly, observed high nymphal mortality under all environmental conditions presented 1n this study indicates that genetic characteris- tics are a supplementary cause of mortality. Effects of temperature (and the prevailing humidities) are believed to be the major cause of developmental differences. The
26 27
Table 2. Percentage of Cheli.nidea vittiger nymphs dying in each life stage when reared at six constant temperatures (Based upon the most advanced stage reached by each nymph). Lubbock, Texas, 1978-79.
Nymphal Instar Adult 1 2 3 4 5 Stage
----~------
17° 100%
..;0.!1 ;z: • 8"'/o 13. 0~ 8.7% 4. 3% 34.8%
...... 7('1 33.3% ':J • ,0 4.4% 17.8% 22.2%
~so ..)• 30.~% 8.7% 2 3. 9% 17.4% 15.2CS
45° 100% 28
Table 3. Relative humj_dit.y ranges recorded for 1:he six temperature treatments. The ranges are based on the lowest and highest relative humid~~ t y readings and also the most common range observed. Lubbock, Texas, 1978-79.
Temperature Most Common Widest Relative Treatn1ent (°C) Relative Humidity Range Humidity Range
50-90% 5 0-..,Cl50.' ,()
75-90% 40-95%
55-90% 40-100~
60-80% 45-95%
40-6 O;o0' 30-65%
40-60% 25-70% 29
h~midity ranges which occurred at each treatment differed
greatly (Table 3).
The Chi-Square analysis permitted a comparison of the
nymphs reaching the adult stage versus the nymphs dying
prior to the adult stage (Appendix B). The analysis re-
vealed a highly significant difference in the percentage of
nymphs reaching the adult stage at the six ~reatments.
Nymphal development beyond the first instar was not
observed for 10, 92, and 29 nymphs reared at the 10°, ~ """'10 ..l. ' and 45°C t::~eatwf~nts, resp€ctively. At the extreme tempera
tures (10° and 45°C) survival did not exceed eight days. . 0 The 10 and 45°C treatments appear to represent point3
beyond the extremes in temperature where C. vittiger nJ~phs
are capable of establishment and survival on the host plant.
~ Nymphs confined at 17°C were partially successful in estab-
lishment on the host plant as is evidenced by the extended
survival of some nymphs. Although unable to molt beyond
the first instar, 27 percent of the 92 nymphs survived 30
days or longer in the first instar stage. One nymph had a
recorded longevity of 49 days. Six nymphs were observed to
have died dur~~g the molting process (firs~ instar to second
instar) at. the 17°C treatment. A caste ski~ was never
observed which would have indicated a successful molt into
the second instar.
Nymphs were able to reach the adult stage when reared 30
0 0 0 at 24 , 31 , and 38 C, respectively (Table 4). Calculated nymphal longevity means of 111.3, 69.9, and 44.3 days were found for the 24°, 31°, and 38°C treatments, respectively.
Analysis of variance of these data indicates a highly sig- nificant difference in the mean number of days required for nymphal development (Appendix C). Comparison of the means with Dunc.an's multiple range test indicates nymphal develop ment at the 24°C treatment was significantly longer than both the 31° and 38°C treatments. The test fails to show a difference in the 31° and 38°C treatments. It is hypothe- sized that a la:r·ger sample size and an equal nlUTiber of replicatio~s within treatments couJd possibly show a significant difference between the 31° and 38°C rates of nymphal development. Regardless of the statistical differ- enees, these data indicate that the rate of nymphal develop- ment is directly 8orrelated with temperature.
The optimal temperature for development can be defined in one of two ways; the temperature that permits the most raptd development, or the temperature that allows the greatest survival to adulthood. At the 24°C treatment, survival of nymphs to the adult stage is greatest but devel opment is slowest. The opposite is true at the 38°C treatr:!ent where survival is lowest and rate of development is h::ghest. In a situation where the optimal temperature for development is desired, a decision would have to be 31
Table 4. Deve2opmental time requirements for those 1st instar Chelinidea vitiiger nymphs reaching the adult stage when reared at three constant temp eratures. Lubbock, Texas, 1978-79.
Days to Reach Days to reaeh Nymph Adult St ao·eb ~ymph Adult Stage
'24°C 4 179 8 141 5 89 10 94 6 63 11 122 7 98 12 104 a. Total Days ...... 890 b. Total ~umber Nymphs ...... 8 c. ~ean Number Days to Reach the Adult Stage ...... 111.25
--31°C 7 43 -- 16 72 9 138 23 46 -:>- 12 71 28 ..;;) 13 93 39 52 14 64 40 85 a. Total Days ...... 699 b. Total Number Nymphs ...... i· ••••• 10 c. Mean Number Days to Reach the Adult Stage ...... 69.9
38°C 2 66 --- 26 39 4 45 28 43 15 53 31 29 24 35 a.. 1,ot al Days ...... 310 b . To t a 1 N1lffi b e r ~ ym p h s ...... 7 c. Mean ~umber Days to Reach the Adult Stage ...... 44.29 32
made as to whether survival to the adult stage or rate of development is more critical.
An interesting observation made during the development study is that the color of the nymph is regulated by temp- 0 erature. At 24 C many of the nymphs had an almost black body while nymphs at 38°C were usually very light green.
Wigglesworth (1950) reports that such a color change influ- ences the heat absorption by the body of the insect.
Staggered Nymphal Development
The nymphal development of the C. vittiger nymphs reared under similar environmental conditions was recorded-
(Appendix D). At the environmental conditions utilized in this experiment, staggered nymphal development, as reported ln the literature, was not observed.
The percent egg eclosion did vary greatly for the seven pairs of adults (Appendix D). Adult palrs 1, 5, and 6 all had a mean egg hatch of zero. Pairs 2, 3, 4, and 7 had a mean egg eclosion of 77%, 64%, 47%, and 20%, respectively.
Although not analyzed, it appears that since the eggs from each pair were produced and held at the same environmental condi~~ons, differences in the percent egg eclosion between eggs of different adults must be associated with the repro- ductive condition of the adult.
The analysis of variance for the difference in the rate of development for nymphs from four different pairs of adults 33
proved to be non-significant (Appendix E). Since these
data did not show a significant difference in the rate of
development of nymphs from different adults, a comparison
of nymphal development of males vers11s females was conducted
(Appendix E'). The rates of development of 13 males were
compared to the rates of 8 females. This test indicates
the developmental time requirements of males does not differ
from that of the females. For a valid statistical test in
both of the previous tests, the assumption had to be made
that the host plants used in the study did not cause ~ny
variation in development (all plants utilized were propa-
gated from the same cactus species and location).
Although staggered nymphal development was not ob-
served in this experiment, it is very possible that under
-- a different set of environmental conditions the phenomenon
would be expressed.
Preoviposition
Preoviposition periods were determined at the 24 0 , 31 0 ,
and 38°C treatments (Table 5). One female produced four
eggs at 17°C but tl1is treatment was dropped from the analysis
due to the small sample size. This female had a preovipo-
sition period of approximately fourteen weeks. Eg~s were
not produced at the 10° and 15°C treatments.
0 The 24° , 3~~ , an d "8°CJ treat~en t s h a d mean preovlposl-. .
tion periods cf 8.67, 5.86, and 4.36 weeks, respectively. 34
Table 5. Preoviposition requirements for Chelinidea vittiger when reared at three constant tempera tures. Lubbock, Texas, 1978-79. ------·------Preoviposition Preoviposition i Female Period (Weeks)aj Female Period (Weeks)a
4 8 8 11 5 7 a. Total VYeeks ...... 26 b. Total Number Females ...... 3 c. ~ean Preoviposition Period (Weeks) ...... 8.67
31°C
1 8 17 6 2 5 18 6 3 6 19 0 4 4 20 12 3 21 7 6 3 22 2 7 6 24 6 8 5 25 9 9 8 27 5 10 5 28 6 ,.7 11 I 29 7 12 3 30 7 13 7 31 7 14 5 32 6 15 ·~1
a. Tot.al ~·Veeks ...... 170 b. Total ::Jurr.ber Females ...... 29 c . .'!ean P:reovj_t)osj_tion P2riod (Weeks) ...... 5.86
~/ Preoviposition period recorded as the number of weeks from initiation of the ~dult stage to the first weekly inspec tion in whtch eggs were observed. 35
Table 5. Continued
Preoviposition I Preoviposition Female Period (Weeks)a Female Period (Weeks)a/
38°C
1 4 5 5 2 4 7 4 3 ..1 13 8 4 5 a. Tot:al ~\leeks ...... 34 b. Total Number Females ...... 7 c. Mean Preovipositional Period (Weeks) ...... 4.86 a; Preoviposition period recorded as the number of weeks from initiation of the adult stage to the first weekly inspection in which eggs were observed. 36
These means are based upon the preoviposition of 3, 29, and
7 females at the 24°, 31°, and 38°C treatments, respectively.
An analysis of variance shows a significant difference in the three preoviposition periods (Appendix G). Duncan's multiple range test does not show a sign_ificant difference in the 31°C (5.86 weeks) and the 38°C (4.86 weeks) treat- ments. The 8.67 week preoviposition period at 24°C is significantly longer than the 31° and 38°C preoviposition periods.
These data suggest the preoviposition period of C. vittiger is inversely correlated with temperature. A temperature increase of only 14°C almost cuts the mean preoviposition time requirement by one-half as seen by the
38° versus 24°C treatments.
The 31° and 38°C preoviposition periods were very similar. Although the means show a slightly longer preovi position period at the 31° versus the 38°C treatment, the data show some of the females at the 31 0 C treatment pro- duced eggs before females at 38°C (Table V).
Reproductive Potential
Observations on the reproduction of C. vittiger indicate the various temperature gradients greatly affect their reproductive potential. Since the relative humidity within each of these treatments varied (Table III), this factor cannot be discounted either. 37
Data pertinent to the reproductive potential of C. vittiger were collected for statistical analysis (Appendix H).
The Chi-Square analysis conducted to determine if a differ ence exists in the percentage of females producing eggs at the six temperatures resulted in a highly significant value
(Appendix I). This indicates the percentage of ovipositing females is affec~ed by temperature. No eggs were produced by 5 and 4 females observed at the extreme temperatures of
10° and 45°C, respectively (Appendix H). Twenty-one females were observed at the 17°C treatment with only one female producing eggs. At 24°C 3 out of 25 females produced eggs
(12%). The critical point for tnitiation of reproduction was located at some point between 24° and 31°C. When twelve females, which had never produced eggs, were transferred from a temperature of 24°C to 31°C, nine of the females produced eggs within a three week period. It was also observed that once the reproductive cycle is initiated by a 31°C exposure, some females will continue to produce eggs at 24°C. The 31°C treatment had 29 ovipositing females out of a total of 32 females (90.6%). Of the three females not producing eggs, two had an adult stage longevity more brief than the mean preoviposition period at that temperature.
A: 38°C the percent ovipositing females started to drop again with only 7 out of 39 females producing eggs (18%).
The mean number of eggs produced per week by ovipositing 38
females was found to be 4.25, 9.02, and 16.07 at the 24°,
310 , and 380 C treatments, respectlvely.. An analysis of variance for these means shows a highly significant differ-
ence (Appendix J). Duncan's multiple range test indicates
the mean number of eggs deposited at 38°C was significantly
higher than both the 31° and 24°C treatments. The means
of 4.25 and 9.02 eggs per week at 24° and 31°C were not
significantly different. If the number of ovipositing
females would have been larger in the 24°C treatment then
the means may have been significantly different.
Weekly egg production records for each female were
compiled over a fourteen week period (Appendix K). Since
egg production occurred mainly at the 24°, 31°, and 38°C
treatments, only these treatments were studied more closely.
~he mean number of eggs produced per week varied at
the 24°, 31°, and 38°C treatments (Figures 5 and 6). When
comparing only the ovipositing females at each treatment,
females at 38°C had a higher reproductive potential t~an
the females at 24° and 31°C (Figure 5). In comparison,
when the mean number of eggs from all the females at each
treatment were evaluated; the reproductive potential was
decreased at the 24° and 38°C treatments (Figure 6). The
reason for this drop is that only 12% and 18% of the females
produced eggs at the 24° and 38°C treatments. The repro
ductive potential of the females at 31°C was essentially 39
35 • 30
0 ·-· : 24 c 25
• 20
'..... 0 ' 10 INS?EC710NS (W~:KLY) Figure 5. Mean number of eggs produced 9er week by the ovipositing Chelinidea vittiger females caged at three constant temperatures for the initial fourteen weeks of the adult stage. Weekly means based on the number of ovipositing females living at each inspection. Lubbock, Texas, 1978-79. 40 35 0 30 *'""''Y : 3 1 c IJ..I ·-· : 24 ° c ....I <( 25 ~ ~ '.J., ~ .,/) 2 0 (_j ;_j 0 z • -/ 7 8 9 10 11 12 lJ 1J. I N S P E C T ! 0 N S ( 'N E EK LY) Figure 6. Mean number of eggs produced per week by Chelinidea vittiger females (both ovipositing and non-ovipositing) caged at three constant temperatures for the initial fourteen weeks of the adult stage. Weekly means based on the total number of females living at each inspection. Lubbock, Texas, 1978-79. 41 the same when considering only the ovipositing females (Figure 5) or all the females (Figure 6)·. This was true because over 90% of the females at 31°C produced eggs and those that did not oviposit died early in the study. It was also observed that for some females, egg production started earlier at 31°C than at 24° and 38°C (Figures 5 and 6). Different preovi~osition periods and adult longevity do not affect the estimated reproductive potential when based on a weekly mean. The cumulative mean number of eggs produced by the ovipositing females was greatest at 38°C and decreased as temperature increased (Figure 7). Three females out of a total of seven produced greater than 200 eggs, each at 38°C. One of these females produced 260 eggs (Appendix H). When considering a cumulative mean based upon all the females at each treatment (ovipositing and non-ovipositing), a different trend is observed. The cumulative mean number of eggs per female at 24° and 38°C treatments is much less than the cumulative mean at 31°C (Figure 8). When consid ering all the females at each temperature, these data clearly point toward a maximum reproductive potential at the 31°C t~eatment. Due to the fact that greater than 90% of the feoales are reproductive at 31°C and oviposition often occurs earlier for females at 31°C, I believe that this temperature ls 42 1 .,1 0 0 120 *..... * : 3 l c ~ ~ < ~ I.U 100 ""- ~ './) ""' 0-- 80 .u 'v''""' 7- so !..U > <( ~ -10 ~ -~ ~ u 20 3 J. 5 6 7 8 9 10 11 1"2 iJ 14 INSPECTIONS (WE=KLY) Figure 7. Cumulative mean number of eggs produced by the ovipositing Chelinidea vittiger females caged at three constant temperatures for the initial fourteen weeks of the adult stage (after Lublinkhof 1976). Lubbock, Texas, 1978-79. 43 ..... • -.: 2 g'"' c ...... 0. I~· 0 *'""*-- J 1I r"- 0 • -.:2 4• c ~ w 100 '"',...~ r~ '-' 3 0 '.J..; 0 z 60 :.u > 4.0 20 -----c ·-~~---·-.a--""• .. 1 ... 3 4 5 6 7 8 9 10 11 12 ,,j 1.J. ! N S P : ( T I 0 N S ( \V E : i( Lv ) Figure 8. Cumulative mean number of eggs produced by Chelinidea vittiger females (both ovipositing and non-ovipositing) caged at three constant temperatures for the initial fourteen weeks of the adult stage (after Lublinkhof 1976). Lubbock, Texas, 1978-79. 44 near optimum for initiating the reproductive cycle in C. vittiger. I also believe that the optimal temperature for reproduction in general lies near 31°C (Figure 8). Adult Longevity Many males and females were still living at the term ination of the study (Appendix L). For this reason, statis tical analysis of these data was not appropriate. Consid- ering only those adults which died of natural causes before termination of the study would bias the test towards short- lived individuals. The data indicate that adult stage longevity is inversely correlated with temperature. The longest survival was at the 24°C treatment. At this treatment some individ- uals lived greater than 300 days until they died due to an equipment breakdown. As the temperature increased or decreased from 24°C, the longevity appeared to decrease. Longevity at the extreme low and high treatments (10 0 and 45°C) was ln most individuals limited to only a few weeks. Longevity of adults was also observed to be short for most individuals at the 31°C treatment. CHAPTER V SUMMARY AND CONCLUSIONS Chelinidea vittiger Uhler, an important native enemy of prickly pear cactus, is of importance as a potential biological control agent. Additional information on the life history of C. vittiger will be of importance in pre dicting the value of this species in a biological control program. The effect of six constant temperature treatments on , the nymphal development and reproductive potential of C. vittiger was examined. Treatments of 10°, 17°, 24°, 31°, 38°, and 45°C were programed into environmental chambers with a 15-hr. photoperiod held cons~ant for each ~reatrnent. In addition, a third experiment investigated the phenomenon of staggered nymphal development reported in the literatu~e. ~ymphal development was found to be influenced by• different temperatures. Survival of the nymphs to the adult stage was found to be inversely correlated with temperature. ~aximum survival to the adult stage occurred at 2 4 °c c> 34% ) . Che1inidea vittiger nymphs were observed to reach the adult stage a~ 24°, 31°, and 38°C. The recorded Yates of development indicate that the rate of nymphal development 45 46 is directly correlated to temperature. Nymphal development to the adult stage was most rapid at 38°C (X= 44.3 days). The optimum temperature of nymphal development varies depending upon the relative importance of nymphal survival to the adult stage versus rate of nymphal development. The test, designed to study the hypothesized, staggered rates of nymphal development (under similar environmental conditions), failed to show differences in the rate of development of C. vittiger nymphs. In addition, there was no difference in the rate of nymphal development in males versus females. It is suspecte~ that under different envi- ronmental conditions this phenomenon may have been expressed. The preoviposition period of C. vittiger is inversely correlated with temperature. Some females, at 31°C, deposited eggs before any other females began oviposition at either lower or higher temperatures. Thus, a temperature near 31°C may be optimum for the initiation of oviposition. The percentage of ovipositing females is affected by temperature. ~early all the females (>90%) were found to be reproductive when reared at 31 0 C. The highest egg production per unit time was observed ~~ong the ovipositi~g females at 38°C, however, only 18% of these females produced eggs. Therefore, 31°C is near the optimum temperature for reproduction. 47 Adult longevity appeared to be inversely correlated with temperature. ~'laximum longevity was observed at 24 °C with decreasing longevity as the temperature decreased or increased. This research has answered some fundamental questions about the reproductive and developmental biology of C. vittiger. The data gathered could prove valuable for future researchers, especially if a biological control program utilizing augmentation is developed. Information on the optimal environmental conditions for rearing large numbers of cactus bugs has obvious practical value. This research also sets the stage for the initiation of life table studies which is a logical step in developing a further understanding of this important cactus pest. LITERATURE CITED Alexander, W. B. 1925. Natural enemies of prickly pear and their introduction into Australia. Commonwealth Australia Inst. Sci. Ind. Bull. 29. 80 pp. Dodd, A. P. 1940. The biological campaign against prickly pear. Commonwealth Prickly Pear Board. A. H. Tucker, Brisbane, Australia. 117 pp. Fullaway, D. T. 1954. Biological control of cactus in Hawaii. J. Econ. Entomol. 47:697-700. Goeden, R. D., C. A. Fleschner, and D. W. Ricker. 1967. Biological control of prickly pear cacti on Santa Cruz Island, California. Hilgardia. 38:579-606. Hamlin, J. C. 1924. A review of the genus Chelinidea (Hemiptera-Heteroptera) with biological data. Ann. Entomol. Soc. Amer. 17:193-208. Hewitt, G. B., E. W. Huddleston, R. J. Lavigne, D. N. Ueckert, and J. G. Watts. 1974. Rangeland Ento mology. Range Science Series, No. 2, February 1974. Belke Printing Co., Denver Colorado. 127 pp. Hunter, W. D., F. C. Pratt, and J. D. Mitchell. 1912. The principle cactus insects of the United States. USDA Bur. Entomol. Bull. 113. 71 pp. Lublinkhof, J. 1976. Development and reproductive potential of the western flower thrips, Frankliniella occidentalis (Pergande) reared at three temperatures. M. S. thesis. Texas Tech Univ., Lubbock, Texas. 75 pp. Mann, J. 1969. Cactus feeding insects and mites. U.S. Nat. Mus. Bull. 256. 158 pp. McAtee, W. L. 1919. Notes on Nearctic Heteroptera. Bull. Brooklyn Entomol. Soc. 14:8-13. Schaffner, J. H. 1938. Spreading of Opuntia in over grazed pastures in Kansas. Ecology. 19(2):348-350. 48 49 Shreve, F. 1931. The cactus and its home. The Williams and Wilkins Company, Baltimore, Maryland. 195 pp. Slater, J. A. and R. M. Baranowski. 1978. How to know the true bugs. Wm. C. Brown Company Publishers, Dubuque, Iowa. 256 pp. Wigglesworth, V. B. 1950. The principles of insect physiology. E. P. Dutton and Co., Inc., NAw York. 544 pp. APPENDICES 50 51 Appendix A. D~ve~opmental data for the nymphs of CheliniQea v1tt1ger reared at six constant temperatures. Lubbock, Texas, 1978-79 . ...... ~I ...... Q) ~I ...... :::1 Q) "0 at ~ ...CI Q) clj.C "0 0£ ~ ~ Q) ..... ,...... ~ ~~ .,..., \.~ ..- ~ ..;...J ·r-i ~ 1/'J. ~ :> ~~ .c •r-i Q) l"""'iQ).-. ~ 1/'J. ~ ;:::..-. Q)..j.J Q)Q .c ·r-1 Q) ,...-1 m en c.. ~~U'l Q)..;...J c ~ ...... , c._. ~c~ 0.. Q)Q ~ ::.c ~ -W·r-1 t.l--1 ..j..) ~ -~ :!j c •r-; .1-J c 0 r:tl E c ~ r:tl ·r-i ~ z o~ ....::l' ~ c 0 c: 0 E--....::Je z o~ ....::l~ E-;....::J._,.. 10°C ~ 1 7-2-'78 1 8 6 7-12 ..L 6 2 7-2 1 8 7 7-12 1 5 3 7-2 1 8 8 7-12 1 5 4 7-2 1 8 9 7-12 1 5 5 7-2 1 8 10 7-12 1 5 17°C 1 7-2-' 78 1 15 19 9-20 1 8 2 7-6 1 11 20 10-2 1 24 3 7-6 1 4 21 10-2 1 24 4 7-6 1 45 22 10-17 1 30 ;) 7-6 1 38 23 10-17 1 30 6 7-18 1 6 24 10-17 1 36 7 7-18 1 6 25 11-10 1 20 8 7-23 1 11 26 11-10 1 6 9 7-23 1 11 27 11-20 1 10 10 7-23 1 11 28 11-20 1 10 11 8-03 1 34 29 11-20 1 24 12 8-03 1 34 30 11-20 1 10 13 8-03 1 34 31 11-29 1 28 14 8-17 1 49 32 11-29 1 22 15 8-30 1 20 33 11-29 1 15 16 9-17 1 25 34 11-29 1 8 17 9-17 1 11 35 12-19 1 8 ... 18 9-17 .1 25 36 12-19 1 8 a; Arabic numbers represent the five nymphal ins tars, "A'' represents the adult stage. b/ Developmental time required for 1st instar nymphs to reach the adult stage. For nymphs dying prior to reaching the adult stage, death was recorded as occurring on the inspection date death was first seen. 52 Appendix A. Continued ...... ,~, ...... <1) ..01 o:!l ...... "'0 0.0 >. (1) ..CI <1) C\!..C "'0 0.0 >. ~ <1) .....,;) ~~ .,..., d...C ~ d C/) d ~ ~~ .,..., .,..... >.-. ~ C/) C\! :;:..-. ..c <1) r-i <1) :JJ ..c ·r-1 (l) .- (I) CfJ. c. <1)~ 17°C (Continued) 37 12-19 1 8 65 5-08 1 44 38 12-19 1 8 66 5-23 1 22 39 1-15-79 1 17 67 5-23 1 9 40 1-15 1 17 68 5-23 1 43 41 1-15 1 24 69 8-06 1 10 42 1-15 1 17 70 8-06 1 24 43 1-15 1 24 71 8-06 1 24 44 1-15 1 35 72 8-06 1 24 45 2-01 1 14 73 8-o6 1 24 46 2-01 1 28 74 8-06 1 30 47 2-20 1 16 75 8-06 1 30 48 2-20 1 16 76 8-06 1 30 49 2-20 1 38 77 8-06 1 30 50 3-08 1 6 78 8-06 1 30 51 3-08 1 12 79 8-06 1 30 52 3-08 1 21 80 8-06 1 30 53 3-08 1 12 81 8-06 1 30 54 3-08 1 9 82 8-06 1 38 55 4-10 1 30 83 8-06 1 10 56 4-10 1 22 84 8-06 1 10 57 4-10 1 9 85 8-06 1 10 58 4-10 1 30 86 8-06 1 10 59 4-10 1 15 87 8-06 1 10 60 4-17 1 9 88 8-06 1 17 61 5-08 1 9 89 8-06 1 17 62 5-08 1 9 90 8-06 1 24 63 5-08 1 9 91 8-06 1 24 64 5-08 1 24 92 8-06 1 38 ~/ Arabic numbers represent the five nymphal instars, "A" represents the adult stage. Developmental time required for 1st instar nymphs to reach the adult stage. For nymphs dying prior to reaching the adult stage, death was recorded as occurring on the inspection date death was first seen. 53 Appendix A. Continued ...... ~I ...... 24°C 1 7-6-78 2 28 16 1-29 5 93 2 7-6 1 4 2)21 17 2-01 1 7 7-6 5 62 18c;2-20 3 58 4 7-6 A 179 19c;2-20 4 71 5 7-6 A 98 2cs 2-2o 3 71 6 7-18 A 63 21-14-17 2 15 f"7 I 8-03 A 98 22 5-08 4 72 8 9-13 A 141 23 5-08 1 9 9 9-20 2 29 24 5-08 2 24 10 10-17 A 94 25 5-08 1 9 11 10-17 A 122 26 5-08 1 9 12 11-10 A 104 27 5-23 5 78 13 11-20 1 10 28 5-23 1 -,..., 9 14 11-29 3 01 29 5-23 1 9 1~/1-15-79 ;:) 107 31°C 1 7-2-78 1 15 5 7-6 1 8 2 7-6 5 66 6 7-18 5 56 3 7-6 5 45 7 7-18 A 43 4 7-6 1 8 8 7-18 1 6 aj Arabic numbers represent the five nymphal instars, "A'' represents the adult stage. b/ Developmental time required for 1st instar nymphs to reach the adult stage. For nymphs dying prior to reaching the adult stage, death was recorded as occurrin~ on the inspection date death was first seen. ~/ Death due to unnatural causes, data excluded from nymphal development data analysis. 54 Appendix A. Continued ...... ~I ...... (]) .CI ~I -... (]) ...:JI '0 0..0 ~ (]) '0 ~..c +-J ""...... ;>, ..,..J ..;..J.w .,..., (]) ~..c .,_l .,_l-1-J .,...., . ~ C/) ~ .+-J .,..., >.....-.-. ~ C/) ..c (]) r--i (]) U2 C\! :>.....-.-. (]).!-) ..c: .,..., (]) ,...... ~ (])Q ~CD~ (]) (J1 ..;..J ·r-i CH ~ (])..;..J (])Q ~ E +-J s:: .!-) .,..., b!· >. ~ ~ s:: .,..., +-J E CH .+-J c: ~ oo8 ~ ~ s:: •...., ..;..J 0 z OH ....4 ~ ~....4-- 00 z QH ....4 ~ ~H'-' 31°C (Continued) 9 7-23 A 138 29 1-15 5 45 10 8-17 1 13 30 2-01 2 14 11 8-30 1 7 31 1-29 2 17 12 9-13 A 71 32 2-20 0- 51 13 9-13 A 93 33 2-20 3 22 14 9-13 A 64 34 2-20 3 28 15 9-13 1 6 35 3-08 2 25 16 9-20 A 72 36 3-08 2 21 17 11-22 1 8 37 4-10 2 30 18 11-22 1 8 38 4-10 1 9 19 11-29 3 22 39 4-10 A 52 20 11-29 1 8 40 4-10 A 85 21 11-29 1 8 41 4-10 5 37 22 12-19 2 15 42 4-17 4 30 .., 23 12-17 A 46 43 5-23 ~ 9 24 12-17 2 10 44 5-23 4 48 25 12-19 1 8 45 5-23 1 9 26 12-17 5 39 27 1-11-79 5 56 28 1-11 A 35 38°C 1 7-2-78 4 59 3 7-2 1 8 2 7-2 A 66 4 7-2 A 45 ~I Arabic numbers represent the five nymphal inst ars, !' Ar' represents the adult stage. b/ Developmental time required for 1st instar nymphs to reach the adult stage. For nymphs dying prior to reaching the adult stage, death was recorded as occurring on the inspection date death was first seen. 55 Appendix A. Continued ""'ct!l Q) ""' ""'ct!l ..GI Q) ""'~I '0 b.L ~ Q) ct!..C "C cr. >. 4-J Q) d..C 4-J +-'l 4-J~ ·1""1 +-'l -i-1~ ·-1 ct! r:r..ct! >,...... >,...... c ·1""1 Q) ct! U1 ~ MQ)CIJ ..c ·1""1 Q) r"'"'IQ)C.O c. Q>+-'l Q)Q ct!t..c~ +-'l ·1""1 0. 38°C (Continued) 5 7-2 5 66 24 11-29 A 35 6 7-23 5 38 25 12-17 1 10 7 8-17 3 19 26 12-17 A 39 8 8-30 1 7 27 12-17 3 32 9 8-30 5 64 28 1-10-79 A 43 10 9-13 1 5 29 1-'0..... ~ 4 29 11 9-13 2 21 30 1-10 3 29 12 9-13 1 5 31 1-15 A 29 13 9-13 1 5 32 1-29 5 ,..., 59 14 9-20 1 I 33 2-20 4 38 15 9-20 A 53 34 2-20 5 38 16C/ 9-20 3 21 35 2-20 4 45 17C/ 10-2 5 38 36 2-20 4 38 18 10-17 4 58 37 4-10 5 30 19 10-17 5 78 38 4-10 4 30 20 11-10 5 34 39 4-10 1 9 21 11-20 1 10 40 4-10 1 9 22 11-20 1 10 41 4-10 4 30 23 11-29 2 15 42 4-17 5 79 a/ Arabic numbers represent the five nymphal ins tars, ··A" represents the adult stage. b/ Developmental time required for 1st instar nymphs to reach the adult s~age. For nymphs dying prior to reaching the adult stage, death was recorded as occurring on the inspection date death was first seen. ~/ Death due to unnatural causes, data excluded from nymphal development data analysis. 56 Appendix A. Continued "C'dl <1,) "C'dl "..CI <1,) "..(:I "'d CJ: ~ <1,) '"0 b.O ~ ~..c .f-) <1,) .,__ ..;....> .f-)..;...> .,....., C'd.C .f-) J,..;l..f.) .,..., ~ r./'J.C'd >- ·.-1 G) C'd r./'1 C'd >- .c ~ <1,) (fJ .,....., <1,) <1,).,__ 38°C (Continued) 43 4-17 4., 37 47 5-23 3 22 44 5-8 j_ 9 48 5-23 1 9 45 5-8 4 37 49 5-23 4 36 46 5-8 1 9 45°C 1 8-9-78 1 7 16 9-17 1 2 2 8-9 1 7 17 9-17 1 2 3 8-9 1 7 18 9-17 1 2 4 8-9 1 7 19 9-17 1 2 ;:) 8-9 1 7 20 9-17 1 2 6 8-17 1 6 21 9-20 1 8 7 8-17 1 6 22 9-20 1 8 8 8-21 1 2 23 9-20 1 8 9 8-17 1 6 24 9-20 1 8 10 8-17 1 6 25 9-20 1 8 11 8-30 1 7 26 10-2 1 4 12 8-30 1 7 27 10-2 1 4 13 8-30 1 7 28 10-2 1 4 14 8-30 1 7 29 10-2 1 4 15 8-30 1 7 a/ Arabic numbers represent the five nymphal instars, "A" represents the adult stage. b/ Developmenta~ time required for 1st instar nymphs to reach the adult stage. For nymphs dying prior to reachinq the adult stage, death was recorded as occurring on the inspection date death was first seen. 57 Appendix B. Chi-Square analysis of the Chelinidea vittiger nymphs reaching the adult stage when reared at six constant temperatures. Lubbock, Texas, 1978-79. Treatments (°C) 10 17 24 31 38 45 Total Nymphs Reaching the Adult Stage 0 0 8 10 7 0 25 Nymphs dying Prior to Adult Stage 10 92 15 35 39 29 220 Total 10 92 23 45 46 29 245 Portion Reaching the Adult Stage .0000 .0000 .3478 .2222 .1522 .0000 .1020 p- .1020 q- .8980 ') 2 x~ value - 38.43** (X .01,5df - 15.09) **Si~nificant0 at the .01 level. 58 Appendix C. Analysis of variance and Duncan's multiple range test for the time Chelinidea vittiger nymphs require to reach the adult stage when reared at three constant temperatures. Lubbock, Texas, 1978-79. Analysis of Variance Source Degrees Sum of of of Mean Variation Freedom Squares Square F Value Treatments 2 17,353.13 8,676.57 10.:14** Error 22 18,109.83 823.17 Total 24 **Significant at the .01 level. Duncan's ~ultiple Range Test Mean Number of Days Temperature ( 0 C) to Reach thea/ Adult Stage- 38 44.3 a 31 69.9 a 24 111.3 b a; Means followed by the same letter are not significantly different at the .05 level. 59 Appendix D. Nymphal development of Chelinidea vittiger nymphs reared under similar environmental conditions. The nymphs originated from seven pairs of adults producing eggs at 31°C. Lubbock, Texas, 1979. r--1 Q.) -. b1l ~ b1l~ 1./l !:l !:l Q.) ~ ~r-<,!sa 0 .,.., bJ) !:l ~ ;:1 Q.) .,..., .c al Q.) E CIJ "'d Q.) ~ 0 !:l u~ E 0 ~;:::...._, :!j z 0 ~CIJ 0.~ b.Jj u •M Q.) o~ CD <1.) .,..., M ~1./l ~~ M C;:J,C Q) ...... ~ 1./l ~0 M Q.) Q.) ~ ~ Q.) C; ~ :I; ~M . ~ > E ~ - Q.) .,..., ..c Q.) 0 b1l u 0'0 0~ ("\ ... .._.. E--~ ~~ z .-< OE---~~CIJ Adult Pair 1 A 4 0.0 B 6 0.0 c 7 0.0 D 3 0.0 Adult Pair 2 A 8 87.5 1 17 (Female) B 11 100.0 -a/ c 8 100.0 4 17 ( :.1al e) 17 0·1ale) 17 (Female) 18 (Sex Unknown) D 9 44.4 E 12 58.3 2 12 (:'lale) 16 (Female) a/ Data other than the percent egg eclosion omitted because some nymphs died of unnatural causes or escaped from the cage. 60 Appendix D. Continued ~ a> -. Q Qj) cil oo 4-1 en 0 Q a> 4-1 ca~~ ·l""'i ·l""'i 00 c 4-1 ;::j (J) ..c cil 4-1 0 Q a>SCIJ"da> ~ 04-1 EO c::r.;s: z 0 ~CI) O.~b..C '-" 0 ·l""'i (J) ·l""'i r-oo. 0 (.!-, bi· (J) 00'11 ~ ~ 0::::4-1 ~..C(J) cil r:n b!; 0 r-1 (J) (J) 4-1 ....,,"-' 0. 4-lb.C ~r-i ,.... ·;::j ::> E a> ·'-' (J) 0 b.O 0 0::: O"d (J) ·l""'i ..c 0 4-1 ~~ ~~ z~ OE-;4-14-JCIJ Adult Pair 3 A 18 100.0 2 17 (Female) 17 (:.!ale) B 21 100.0 c 17 100.0 ... D 10 80.0 ..L 16 01ale) E 7 42.9 F 13 15.4 2 14 (Female) 15 (Female) G 12 25.0 H 11 72.7 -a/ I 13 15.4 J 7 14.3 Adult Pair 4 A 12 66.7 1 16 (Female) B 10 100.0 5 18 C·1ale) 18 ( ~A'al e) 20 C1ale) 20 o·~ale) 20 (Sex Unknown) c 20 80.0 -a/ D 10 30.0 E 14 21.4 2 12 (Male) 13 (Male) F 14 0.0 G 11 0.0 H 6 0.0 ~/ Data other than ~he percent egg eclosion omitted because some nymphs died of unnatural causes or escaped from the cage. 61 Appendix D. Continued ,...... ~ Adult Pair 4 (Continued) I 12 33.3 J 13 84. 6 K 16 100.0 2 14 (Hale) 17 (Sex Unknown) L 6 66.7 Adult Pair ;:) A 10 0.0 B 4 0.0 Adult Pair 6 A 3 0.0 B 8 0.0 c 6 0.0 Adult Pair 7 A 5 20.0 1 14 (Female) B ;:) 20.0 1 13 (Hale) 62 Appendix E. Analysis of variance for the immature develop ment of Chelinidea viLtiger. Analysis is based upon the egg incubation and nymphal development periods combined for 24 nymphs originating from four pairs of adults. Lubbock, Texas, 1979. Analysis of Variance Source Degrees Sum of of of :·.1ean Variance Freedom Squares Square F Value Treatments 3 19.0048 6.335 1.148 Error 20 110.3286 5.51643 Total 23 (F - 3.10) .05, 3 and 2 0 d.f. 63 Appendix F. Analysis of variance for the comparison of the immature development of the males versus females of Chelinidea vittiger. Analysis is based upon the combined egg incubation and nymphal development periods for eight females and thirteen males reared under similar environmental conditions. Lubbock, Texas, 1979. Analysis of Variance Source Degrees Sum of of of 0.1ean Variance Freedom Squares Square F Value Treatments 1 0. 148 0.148 .026 Error 19 108.85 5. 729 Total 20 (F 4.38) .05, 1 and 19 d.f. = 64 Appendix G. Analysis of variance and Duncan's multiple range test for the preoviposition time require ments of Chelinidea vittiger females producing eggs when reared at three constant temperatures. Lubbock, Texas, 1978-79. Analysis of Variance Source Degrees Sum of of of Mean Variance Freedom Squares Sauare F Value Treatments 2 30.618 15.309 4.02* Error 36 136.972 3.805 Total 38 *Significant at the .05 level. Duncan's Vultiple Range Test Mean Preoviposition Tempera t ure (oC) Period (Weeks) a/ 38 4.86 a 31 5.86 a 24 8.67 b a/ Means followed by the same letter are not significantly different at the .05 level. 65 Appendix H. Reproductive behavioral responses of Chelinidea vittiger females reared at six constant temp eratures. Lubbock·, Texas, 1978-79 . ..- r.n ..- ~ ~'"0 C) ~- ~- 0 C) C) 0 r.n 0 r.n ..... '"C S: ·r-i .!a ·r-i ~ ~ ~ C)'-' +-l C) ~ (]) ...... ~ CJ) ·r-i C) C,) C) r.n r:/1 C,) cd ~ r:/1~ ;j;::: bJ; c ::<: .W+J 0'-" 0 b.l; ~ 0.. C) [/) '"0'-" ...., 0.. 'Z; 0 ~ (])·r-i C) > ·r-i '"0 ~'"0 (]):>'"0 r--" +JC) :> 0 r-1 0.. 0 ·3:0Q :j .,_ _..... ~c.o 0 ...., cd r.n c ll ·- c = c (]) ~ ~ C.!: b.O~ z ~ ~ ~ :J) "0 c ~ (]) c b.C b.Q(]) Q) ,....._.. '"""' ~ ~~ ~~ ~~ ~c.. IX c "-" ;:-'~ 10°C 1 2 2 2 3 2 4 3 5 3 17°C 1 ;) 2 14 3 19 14 4 6 .667 4 13 5 33 6 31 7 32 8 27 9 21 10 12 11 2 12 17 13 6 14a/ 19b/ 1~a/;)- 1~/ 1~/ 8 17a/ 1~/ lSa/ 18b/ ~/ Female from the Jayton, Texas colony; all other femal~s from the Dumas, Texas, colony. b/ Study terminated prior to death of the female. 66 Appendix H. Continued U'J ,...... ~ c-c 17°C (Continued) 19a/ 9 2~/ 13b/ 21 1~ 24°C 1 4~/ 2 4~/ 3 ?)2! 4 41 8 133 34 3.912 ;) 35 7 140 29 4. 828 6 29S:./ 7 11 8 19 11 36 9 4.000 9 11c/ 10 31b/ 11 2~/ 12 27b/ 13 6 14~:1 1~/ 15a/ 1g.£/ .,~/ 2 i..,a/,_ 17b/ 1~/ 1~/ 1#/ 1~/ a/ Female from the Jayton, Texas, colony; all other females from the Dumas, Texas, colony. b/ Study terminated prior to death of the female. ~/ Death due to unnatural causes. 67 Appendix H. Continued -VJ ~ ~"d J.) - ~- l::::- 0 Q) Q) 0 U'1 0 U'1 ·.- "0 .,....., ~ a;....._,_,s= ·r-1 ~ +-' ::s +-' Q) +-' Q) .,...., r-1 0.0 ·r-1 Q) C,) C) U'1 r.n C,) oj >. U'l~ ;:j~ a.c 8 ><: ~~ 0...... ,_, b.G~ ~ Q) r:r.J. .,...., 0 '"d"-" 0. z 0 ~ Q)·r-1 Q) :> .,...., '"d H'"d Q.):>'"d r-1 ~ Q.) :> 0 r-1 0 • 3: 0 0 c. Q) .,..., :d .-c.n 0 ·r-1 ~ U'1 ·r-1 0 ;:: ::: Q Q.) H +-'0.0 b.CH Z H H)..... -J.) 'ij. 0 H.Q) 0 b.D b..GQ) Q.) c.. 'J.) ~ 31°C 1 1~/ 8 19 3 f3.333 2 gS:_/ 5 75 4 18.750 3 21 6 178 16 11.125 4 8 4 62 5 12.400 5 5 3 42 3 14.000 6 7 3 56 5 11.200 7 10 6 40 5 8.000 8 20 5 206 16 12.875 9 20 8 37 13 2. 846 10 14 5 172 10 17. 200 11 17 7 31 11 2. 818 12 11 3 108 9 12.000 13 16 7 117 10 11.700 14 25 0 125 21 5.952 15 24 4 78 21 3.714 16 2 ~/ Female from the Jayton, Texas, colony; all other females from the Dumas, Texas, colony. El Study terminated prior to death of the female. c/ Death due to unnatural causes. 68 Appendix H. Continued -.. r.n -.. ~ - ...... u (]) c-.. ::::::-.. 0 Q (]) 0 r.n 0 r.n ·I'"'! "d s: ·r-1 ~ ·~ ~ ~ ~ 17 17 6 54 12 4.500 18 19 6 79 14 5.643 19 22 5 202 18 11.222 2 QE:.I 16b/ 12 11 5 2.200 21a/ 19b/ 7 173 13 13.308 22a/ 19- 2 108 18 6.000 2~/ 4 2¢1 19b/ 6 189 14 13.500 25a/ 1g£/ 9 66 11 6.000 2~/ 7 27a/ 12, I 5 51 8 6.375 2 p}:_/ 140 13 10.769 lsE- 6,.., 29a/ 9C/ I 18 3 6.000 3~/ 1~/ 7 193 12 16.083 31a/ 18b/ 7 81 12 6.750 32a/ ls£1 6 30 13 2.308 38°C 1 19 4 207 16 12.938 2 8 4 147 5 29.400 3 21 4 260 18 14.444 ,1 4 26.150 -:1: 8 5 107 8.875 ;) 12 5 71 8 6 4 a/ Female from the Jayton, Texas, colony; all other females from the Dumas, Texas, colony. b/ Study terminated prior to death of the female. ~/ Death due to unnatural causes. 69 Appendix H. Continued -:.!1 ~ C'"d- (1) ::::- ::::::- 0 C) (1) .J Cf1 0 Cf1 ·~ u s: ·~ ~ ·~ ~ ..!-) :::s C)'--' 4-J C) ..!-) C) ·~ r--1 b.D ·~ C) :,) C) Cf1 Cf1 () ~ >. r.n;s:: ::::s: J.£ 0 ~ 4-J~ 0'--' 0 u'--' b£~ ~C) rJJ. ·~ ~ z 0 ~ (1)·,...; C) > ·~ '"d ~"d Q):>'"d r-1 4-JQ) :> 0 ,_., ~ 0 . s: 0 0 :t:l I"""" CD :J ·~ ~ Cf1 ·.-I 0 38°C 7 17 4 216 14 15.429 8 3 9 3 10 1 11 4 12 2 13 16 8 42 9 4.667 14 5 15 1 16 8 17 3 18 1 19 6 20 8 21 3 22 4 23 3 2c/ 2~ 25 ;:) 26 2 27a/ 4 2~/ 6 29a/ 3 3rftl 3 31a/ 3 ,2a/ 1 .) - """I 33 3 ~/ Female from the Jayton, Texas, colony; all other females from the Dumas, Texas, colony. ~/ Death due to unnatural causes. 70 ~ppendix H. Continued en -y _.. :::::"0- 34 11 3~/ 3 36 4 37 4 38 4 39 4 q~. -oc 1 2 2 3 3 1 4 1 a/ Female from the Jayton, Texas, colony; all other females from the Dumas,,Texas, colony. 71 Appendix I. Chi-Square analysis for egg production of Chelinidea vittiger females reared at six constant temperatures. Lubbock, Texas, 1978-79. Treatments (°C) 10 17 24 31 38 45 Total Eggs Produced 0 1 3 29 7 0 40 No Eggs Produced 5 20 22 3 32 4 86 Total 5 21 25 32 39 4 126 Portion Laying Eggs .0000 .0476 .1200 .9063 .1795 .0000 .31746 p = .31746 q- .68254 x2 value= 70.396** cx2.o1,5ct.f. - 15.09) **Significant at the .01 level. 72 Appendix J. Analysis of variance and Duncan's multiDle .1. range test for the reproductive potential of Chelinidea vittiger females producing eggs when reared at three constant temperatures. Analysis is based upon the mean number of eggs produced per week over the lifetime of each female but excluding the preoviposition period. Lubbock, Texas, 1978-79. Analysis of Variance Source Degrees Sum of of of _r... rean Variance Freedom Squares Square F Value Treatments 2 384.987 192.492 6.26** Error 36 1106.409 30.734 Total 38 **Significant at the .01 level. Duncan's Multiple Range Test ~1ean ~umber a/ Tempera ·cure ( oC) of eggsjweek- 24 4.25 a 31 9.02 a 38 16.07 b aj Means followed by the same letter are not significantly different at the .05 level. 73 Appendix K. Egg production in the initial 14 weeks of the adult stage for Chelinidea vittiger females reared at six constant temperatures. Lubbock, Texas, 1978-79. Weekly Egg Counts Female 1 2 3 4 5 6 7 8 9 10 11 I 12 13 14 10°C 1 2 3 4 ;) 17°C 1 2 3 4 4 5 6 f'( I 8 9 10 11 12 13 14a/ 1~/ 1~/ 17a/ 1~/ 1¢/ 2~/ 21a/ a/ Female originated from nymphs collected near Jayton, Texas; all other females from the Dumas, Texas, colony. 74 Appendix K. Continued Weekly Egg Counts Female 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1 2 3 4 25 10 ;) 30 31 22 15 14 6 7 8 8 8 12 5 9 10 11 12 13 14a/ 15a/ 16~/ 17a/ 1~/ 19a/ 2~/ 21 a/ 22~/ 2~/ 2~/ 25a/ 6b/ 1 1_~/ - 2 34 39 2 2 6 9 15 32 3 8 13 12 13 a/ Female originated from nymphs collec~ed near Jayton, Texas; all other females from the Dumas, Texas colony. b/ Female died of unnatural causes and data was omitted from the Clli~ulative mean data. 75 Appendix K. Continued Weekly Egg Counts Female 1 2 3 4 5 6 7 8 9 10 11 12 13 14 31°C (Continued) 4 24 24 1 13 ;) 12 25 5 .., 6 13 24 9 9 ..L ""7 I 24 1 15 37 1 16 7 16 31 22 31 8 10 ,.... 9 6 ;) ;) 11 3 10 35 16 12 19 28 27 19 10 4 2 11 10 7 5 3 2 12 10 11 14 12 7 21 33 13 3 10 18 14 10 32 13 14 2 6 16 10 6 5 18 7 7 10 15 9 11 8 8 11 8 -11.... 16 5 8 3 11 11 10 17 n 18 2 13 8 4 5 10 26 4- 19 14 22 28 34 6 8 8 7 2 eft_/ 2 7 21a/ 8 13 10 19 16 17 22a/ 2 5 2 8 13 14 3 2~/ 2¢/ 22 33 23 7 8 2~/ 5 17 4 15 26a/ 27a/ 11 17 3 20 2~/ 17 20 25 11 12 4 2¢/ 6 6 6 30a/ 18 7 19 32 23 20 27 j_ 31~/ 12 14 10 20 14 3 32a/ 3 4 5 38°C ') 3 ~ 25 1 6 20 9 35 22 27 20 2 10 67 26 15 29 1 24 10 26 3 23 47 5 21 20 10 4 4 52 8 47 a/ Female originated from nymphs collected near Jayton, Texas; all other females from the Dumas, Texas colony. 76 Appendix K. Continued Weekly Egg Counts Female 1 2 3 4 5 6 7 8 9 10 11- 12 13 14 3'8°C (Continued) 5 14 1 14 21 16 5 6 7 52 26 8 17 13 22 28 14 30 2 8 9 10 11 12 13 1 10 8 11 7 2 14 15 16 17 18 ' 19 20 21 22 23 24 2~/ 26a/ 27a/ 28a/ 2¢/ 3~/ 31a/ 32a/ 33 34 ..;D--1"),...a/ 36a 37a/ 3~/ 39a/ ~/ Female originated from nymphs collected near Jayton, Texas; all other females from the Dumas, Texas colony. 77 Appendix K. Continued Weekly Egg Counts Female 1 2 3 4 5 6 7 8 9 10 11 12 13 14 45°C 1 2 3 4 78 Appendix L. Longevity of the adult stage in Chelinidea vittiger females and males when reared at six constant temperatures. Lubbock, Texas, 1978-79. Adult Stage Adult Stage Female Longevity (Da"ys)a/ Male Longevity (Days)a/ 10°C 1 12 1 12 2 12 2 19 3 12 3 24 4 20 4 10 ;) 21 5 17 17°C 1 36 1 145 2 99 2 161 3 134 3 112 4 92 4 104 5 232 5 69 6 220 6 183 7 221 7 215 8 186 8 35 9 149 9 180 10 82 10 89 11 12 11 88 12 117 12 30 13 133 13b/ 40 131E,/ 14 32 14b/ 126£:../ 15 144 15-b; 1R 47 53 -- b I 16-fi; 17- 109 17b/ 12&£1 --- b I 126E,/ 126C/ 18b/ 1Sfi; 12eE-/ 19b/ 60 19b/ 20.::: 88 2~ 89 21 12~/ 21 101 aj Death was recorded as occurring on the inspection date death was first seen. b/ Adult from Jayton, Texas colony; all other adults from Dumas, Texas colony. cj Study terminated prior to death. 79 Appendix L. Continued Adult Stage Adult Stage Female Longevity (Days)a/ Male Longevity (Days)a/ 24°C 1 306d/ 1 54 d/ 2 307d/ 2 gd/ 3 5~ 3 5~ 4 284 4 306d/ 306d/ 5 242d/ 5 /" 0 20~ 6 23 7 76 7 256~/ 8 131d/ 8 12 9 72- 9 50 10 216c/ 10 167c/ 11 202c/ 11 166c/ 12 192c/ 12 8oS:. I 13 81 13b/ 40 126:;;./ 14 130 14-fi; 15 71 15b/ 131~/ 16 63 16b/ 10 121 c/ 17b/ 104 17b/ 126c/ 131c/ 1SE; 18-£; 126~/ 19fi; 10 19-£; 118c/ 131C/ 2G-fi; 20b/ 126c/ 118c/ 21b/ 21b/ 22- 126C/ 22b/ 118~/ 45 23 31 2 3-fi I 45 24 31 24-E; 2S.:: 11~/ 25 11 31°C 1 71d/ 1 65d/ 2 57d/ 2 57- a/ Death was recorded as occurrlng on the inspection date death was first seen. b/ Adult from Jayton, Texas colony: all other adults from Dumas, Texas colony. ~/ Study terminated prior to death. d/ Dea~h due to unnatural causes. 80 Appendix L. Continued Adult Stage Adult Stage Female Longevity (Days)a/ Longevity (Days)a/ 31°C (Continued) 3 148 3 76d/ 4 56 4 56d/ 5 36 5 83 6 44 6 54 7 68 7 47 8 138 8 121 9 137 9 119 10 95 10 111 11 115 11 135 12 75 12 110 13 110 13 132 14 172d/ 14 159 15 166- 15 30 16 12 16 152 17 117 17 33 18 131 18 158 19 59 19b/ 150 108 20 152 20fi; 131c/ 21 116 21b/ "36 22b/ 131C/ 22 2:3:5; 26 23 11 131£./ 24b/ 121d/ 24b/ 1~ 2~ 131c/ 25b/ 26c/ 47 26- 26 27b/ 131C/ 27 81 12~/ 28b/ 131c/ 28 2g$./ 68d/ 29 6oE( 30 123C/ 3J.!-I 68 123c/ 31b/ 12~/ 31 32b/ 124c/ --32 12~/ 33b/ 10 a/ Death was recorded as occurring on the inspec~ion date death was first seen. b/ Adult from Jayton, Texas colony; all other adults from Dumas, Texas colony. £./ Study terminated prior to death. d/ Death due to unnatural causes. 81 Appendix 1. Continued Adult Stage Adult Stage Female Longevity (Days)a/ Male Longevity (Days)a/ 38°C 1 132 1 81 2 52 2 eo£- I 3 143 3 143 I 4 52 4 6o£. 5 79 5 8oS-I 6 26 6 19 7 113 7 110 8 22 8 16 9 23 9 7 10 9 10 23 a 11 31 11 v 12 12 12 31 13 107 13 122 14 37 14 37 15 8 15 42 16 53 16 38 17 23 17 10 18 10 18 23 19 45 19 40 20 53 20 61 21 19 21 137 22 25 22 59 12 23 23d/ 23 24 16- 24 12 25 34 25 12 12 26 12 26b/ 27 12 27b/ 26 39 28 24 2Sfi; 19 29 10 29b/ 18 30.:::. 19 30 a/ Death was recorded as occurring on the inspection date death was first seen. b/ Adult from Jayton, Texas colony; all other adults from Dumas, Texas colony. £/ Study terminated prior to death. d/ Death due to unnatural causes. 82 Appendix L. Continued Adult Stage Adult Stage Female Longevity (Days)a/ ~.. fal e Longevity (Days)a/ 38°C (Continued) 31b/ 19 53d/ 32b/ 25 11 33 24 47 d/ 14- 3~b/ 74 3o- 18 11 36 25 26 37 25 33 38 25 19 39 31 19 26 33 12 33 33 39 39 39 11 81c/ 25 39 11 11 1 17 1 17 2 18 2 17 4 3 11 3 38 4 7 4 5 18 6 9 a/ Death was recorded as occurring on the inspection date death was first seen. b/ Adult from Jayton, Texas colony; all other adults from Dumas, Texas colony. ~/ Study terminated prior to death. d/ Death due to unnatural causes.