Legume Host Impact on Performance of Adult (Westwood) (: )

A. R. PANIZZP AND F. SLANSKY, JR. Department of Entomology and Nematology, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida 32611

Environ. Entomol. 14: 237-242 (1985) ABSTRACT Laboratory studies of adult PiezodorU8 guildinii feeding on the seeds or pods of five legumes demonstrated that this polyphagous stink bug exhibits differences in repro- ductive parameters, survival, longevity and body weight depending on food source. Results of these laboratory studies, coupled with previous field observations, suggest that Indigofera hirsuta and Crotalaria lanceolata serve as important wild hosts in the seasonal phenology of P. guildinii.

Piezodorus guildinii (Westwood) is a neotropical lanceleaf crotalaria (Crotalaria lanceolata E. Mey.) pentatomid with numerous species of wild and green pods, soybean (Glycine max [L.] Merrill var. cultivated plants reportedly serving as hosts; the 'Bedford') pods at full green bean stage (R6 of fruiting structures of these plants are the primary Fehr et al. [1971]), air-dried soybean seeds at har- feeding sites (Panizzi and Slansky 1985a). This stink vest maturity (R8 of Fehr et al. [1971)), green bean bug is a serious pest of soybeans in South America; (Phaseolus vulgaris L.) green pods, and raw, several studies have investigated the effect of its shelled peanuts, Arachis hypogaea L. (the latter feeding on seed yield and quality, and economic two foods were commercially obtained and their thresholds have been determined (Panizzi and varieties were unknown). Slansky 1985a). However, little information is I. hirsuta and C. lanceolata were chosen to available on the host plants of P. guildinii in North compare with soybean because they apparently are America, or on the impact of various plants on its two important wild hosts of P. guildinii during biology in either North or South America. Because autumn in this area of Florida (Panizzi and Slan- P. guildinii apparently prefers to feed on various sky 1985b). Peanuts, if suitable as a food for P. legumes, critical evaluation of the suitability of guildinii, would be readily available commercially these plants is necessary to determine their poten- for use in laboratory rearing; green beans are com- tial as hosts, and in particular the role of various monly used as suitable laboratory food for another wild plants in serving as sources of stink bugs col- polyphagous stink bug, Nezara viridula L. (Harris onizing crop plants. The objective of our study was and Todd 1981). to determine the impact of certain legumes on Food was replaced every 2 days and water reproduction, survival, longevity, and body weight (moistened cotton balls) was provided for adults of adult P. guildinii. feeding on the mature soybean seeds and peanuts. Rearing jars were randomly placed in an environ- mental chamber maintained at 25 ± 2°C and Materials and Methods 70 ± 10% RH under a photoperiod of LD 14:10. During November 1983, fourth and fifth instar Daily records were made of female oviposition and nymphs of P. guildinii were collected from the fecundity (number of egg masses and eggs per wild legume hairy indigo (Indigofera hirsuta L.) mass), egg fertility, and adult survival. Fresh body growing near a field of mature soybeans in the weight (mg) was measured weekly until death of University of Florida Agronomy Farm (Alachua the stink bugs, using a Mettler AC-100 electronic County, north-central Florida). They were reared balance. Data were analyzed with analysis of vari- in the laboratory on I. hirsuta pods. Immediately ance and Duncan's multiple range test using the after the imaginal molt, adults were sexed by vi- Statistical Analysis System (Ray 1982). sually examining the genitalia (McPherson 1982). Single female-male pairs were placed in glass rearing jars (17.0 by 6.5 cm) covered with filter Results and Discussion paper. Ten pairs each were fed each of the follow- Reproduction. Most females feeding on I. hir- ing legumes: I. hirsuta green (immature) pods, suta or C. lanceolata pods oviposited and laid their first eggs when ca. 13 to 14 days old, whereas on

I Current address: Centro Nacional de Pesquisa de Soja, EM- other foods tested many females failed to oviposit, BRAPA, Caixa Postal 1061, Londrina, PR., 86100, Brasil. and the timing of those that did was highly vari-

237 238 ENVIRONMENTAL ENTOMOLOGY Vol. 14, no. 3

Table 1. Reproductive perfonnance of P. guildinii females feeding on six different foods in the laboratory

Females Female age (days) at No. per female'> Egg fertility" (%) Food ovipositing first oviposition' Egg masses Eggs (x ± SE) (no.) (x ± SE) (f ± SE) (x ± SE) I. htrsuta pods 90.0 12.9 (±1.0)c 12.2 (±2.2)a 204.8 (±35.9)a 73.2 (±3.5)a (9) C. lanceo/ata pods 90.0 14.1 (±1.7)bc 5.2 (±1.1)ab 58.2 (±14.6)b 62.6 (±12.6)a (9) Green beans 70.0 46.1 (±16.4)a 4.0 (±1.2)bc 45.0 (±16.9)bc 67.4 (±13.0)a (7) Soybean pods (R6) 40.0 31.2 (±14.7)abc 2.2 (±1.3)b& 28.0 (±16.0)bc 45.5 (±26.4)a (4) Soybean seeds (R8) 30.0 33.7 (±12.3)ab 2.0 (±0.6)bc 9.3 (±2.4)cd 41.1 (±21.6)a (3) Peanuts 30.0 33.0 (±1O.8)abc 1.3 (±0.3)cd 3.3 (±1.2)d 30.0 (±15.3)a (3)

• Data transformed to log(x + 0.1) for analysis. Means followed by the same letter are not significantly different (P < 0.05; Duncan's multiple range test). b Data from females ovipositing. C Data transformed to arc sine for analysis. Means followed by the same letter are not significantly different (P < 0.05; Duncan's multiple range test). d Data were included in the analysis, although not normally distributed.

able and greatly delayed (Table 1). Females feed- served, although, like males, they tended to live ing on 1. hirsuta produced significantly more egg longer on green beans (Fig. 1). masses (2- to lo-fold more) than females on all Males lived a mean of ca. 21 days longer than other foods except C. lanceolata, and their fecun- females on green beans and ca. 37 days longer on dity was significantly greater than on any other soybean pods, although only the difference on soy- food (Table 1). Fecundity of females feeding on bean pods was significant (Fig. I). Reduced sur- mature soybean seeds or peanuts was <5% of that vival and longevity of reproductive females com- of females on 1. hirsuta. Egg fertility varied from pared with males may be due to the great strain 73% for females feeding on 1. hirsuta to 30% for of egg production, which, by diverting energy and females on peanuts, although these differences were nutrients away from the maintenance of the fe- not significant (Table 1). male, shortens its life (Slansky 1980a,b). Males of Compared with females on 1. hirsuta, the re- two other hemipterans, Oncopeltus fasciatus duced reproductive performance of females on the (Dallas) and Euschistus heros (Fab.), live longer other foods could have been caused either by re- than females (Slansky 1980a, Villas Boas and Pa- duced quality of these foods and/or by the switch nizzi 1980). from nymphal diet (1. hirsuta) to the different adult On peanuts and on mature soybean seeds, where foods. We are unable to evaluate this because we egg production (and thus presumably reproduc- did not raise nymphs on foods other than 1. hirsuta tive strain) was very low, the longevity of female and then switch them to different foods as adults. P. guildinii was similar to or greater than that of Fecundity in other species of seed-sucking males, respectively (Fig. 1), apparently supporting is affected by both nymphal and adult foods (AI- the strain of reproduction hypothesis. However, Munshi et al. 1982, Ananthakrishnan et al. 1982, substantial female mortality on these two foods, Kester and Smith 1984, Panizzi and Herzog 1984), and on soybean pods, occurred prior to oviposition. but the impact of switching foods from nymph to Also, survival of the sexes was similar on I. hirsuta adult has not been rigorously examined. and C. lanceolata in spite of high egg production, Survivorship and Longevity. Ninety percent or and survival and longevity of P. guildinii females more of both sexes feeding on green beans and on the different foods was similar (Fig. 1) in spite males on soybean pods survived up to 40 days (Fig. of large differences in fecundity (and thus presum- 1). Survival of adults on most of the other foods ably large differences in reproductive strain; Table ranged from ca. 40 to 60%, but no males on ma- 1). Thus, these results, and the similar longevity of ture soybean seeds survived to day 40. Survival the sexes in several other hemipterans (Miner 1966, and longevity of adults on 1. hirsuta beyond 40 Panizzi and Smith 1977, AI-Munshi et al. 1982, days and on C. lanceolata beyond 30 days could Panizzi and Herzog 1984), suggest that reproduc- not be determined because of lack of pods. Males tion is not a life-shortening strain on females of lived significantly longer when they fed on green these species. In P. guildinii, differences in surviv- beans or soybean pods than on peanuts or mature al and longevity are apparently determined by food soybean seeds; for females, no significant differ- quality differences acting more directly on the ences in mean longevity among foods were ob- physiology of these stink bugs. June 1985 PANIZZI AND SLANSKY: HOST PLANT IMPACT ON ADULT P. guildinii 239

••.••. 9 ...~ ~ , CROTALARIA " , LANCEOLATA d'''

o

-~100 ---o. ~ -a.. "00---<> J: en a: GREEN BEANS SOYBEAN o PODS (Re) > Longevity (days) = > 99.1 t 13.8 (d') e8.1 t 13.1 (d') a: 2 17.8 t 11.8(9) 51.2 t 12.e(9) en:> o

q,...... , SOYBEAN "", SEEDS (R8) , ,

23.3 t 3.1 (d') '.t, 45.5 t 9.8 (9) 'b...... o o 10 20 30 40 0 10 20 30 40 LONGEVITY (DAYS) Fig. 1. Survival up to 40 days and longevity of adult P. guildinU feeding on six different foods. Longevity data for adults on I. hirsuta and C. lanceolata were not obtained because pods of these plants were not available in the field after 40 days. necessitating termination of these two treatments. The only significant differences in mean longevity were between males and females on soybean pods, and between males on green beans and soybean pods versus males on peanuts and mature soybean seeds (P < 0.05; Duncan's multiple range test).

Body Weight. Fresh weight gain by P. guildinii tide, flight muscle and gonad formation, and varied with age, sex, and host plant (Table 2). Fresh nutrient storage in the fat body (Slansky 1980a, body weight increased significantly up to day 8 or Kester and Smith 1984). Lipid content of newly 15 for females and males fed I. hirsuta or soybean molted female P. guildinii feeding on green beans pods, and for females fed green beans or C. lan- doubled by day 4, after which it leveled off (un- ceolata pods, but not for females and males fed published data). Because body weight tended to peanuts or mature soybean seeds, or males fed level off after day 15, adults feeding on I. hirsuta green beans or C. lanceolata pods. High food in- pods, soybean pods or green beans tended to weigh take and increase in weight during the teneral pe- more than adults on C. lanceolata, peanuts or soy- riod in certain hemipterans is associated with cu- bean seeds throughout the rest of their lives. Fe- 240 ENVIRONMENTAL ENTOMOLOGY Vol. 14, no. 3

.s

=Q Ill) ;a= ...~ '"~ f

~ - 1l os Cl 11 ... Q

c os'" 1J c '" c os '" -=c ., 1J -=c os ~ >. os ~ o ~ c.i ~ c:s (I) ~ June 1985 PANIZZIANDSLANSKY:HOST PLANT IMPACTON ADULT P. guildinii 241

Table 3. Fresh body weight (mg) of adult female P. proteins, and presence and concentration of alle- guildinii on the day nearest to first oviposition (mean ± lochemicals) contributing to these differences re- SE, range in parentheses below). Because weights were m"asured weekly,this day ranges from 1 to 7 days before quires further investigation. oviposition The abundance of P. guildinii eggs, nymphs, and adults on I. hirsuta and C. lanceolata plants Food(no.females) Bodyweight growing near soybean fields in north-central Flor- I. hirsuta 64.4 (±3.4) ida (Panizzi and Slansky 1985b), when coupled (9) (51.7-79.5) with the suitability of I. hirsuta and C. lanceolata C. /anceo/ata 58.7 (±4.8) for adults, strongly suggests that these two plants (8) (41.9-77.4) serve as important wild hosts, maintaining popu- Greenbeans 66.0 (±2.8) lations of this stink bug when cultivated plants are (7) (52.1-74.2) unavailable. In Colombia, I. hirsuta and Crota- Soybeanpods(R6) 71.1 (±6.3) laria pallida Aiton apparently provide sources of (4) (61.0-88.4) P. guildinii that infest soybeans (Hallman 1979). Soybeanseeds(R8) 58.7 (±1.8) (3) (56.5-62.2) Fruiting structures of I. hirsuta and C. lanceolata Peanuts 68.2 (±5.8) are present only in late summer and autumn in (3) (59.5-79.3) north-central Florida. Thus, P. guildinii undoubt- edly must exhibit seasonal shifts in host-plant use, Therewerenosignificantdifferencesamongmeans(P > 0.05; but the extent to which individual stink bugs ex- analysisof variance). hibit polyphagous feeding habits is unknown. Al- though soybean pods do not appear to be a highly suitable food source (Panizzi and Smith 1977), P. guildinii is commonly found in soybean fields in males tended to weigh more than males, although South America (Panizzi and SIansky 1985a) and differences between the sexes were significant on seems to be increasing in abundance on soybeans only some of the foods at certain ages (Table 2). in north-central Florida (Menezes 1981). Pods in It has been proposed that consumption of a par- earlier stages than those used here may be more ticular amount of suitable food or the storage of a suitable foods for P. guildinii, or these later-stage particular level of nutrients may serve as an inter- pods may be suitable foods if adult stink bugs are nal stimulus contributing to the initiation of neu- able to feed occassionally on other foods as well. roendocrine events leading to egg production in Further research on food-switching behavior of P. O. fasciatus (Slansky 1980b). In our study, age at guildinii is necessary to resolve these questions. first oviposition was quite variable (see Table 1 for mean values); for individual females, it ranged from 6 days on I. hirsuta to 134 days on green Acknowledgment beans. Although there were significant differences We thank W. A. Jones, R. I. Sailer, and C. M. Smith in mean body weight among females feeding on for their comments on an earlier draft of this paper. the different foods at each age (Table 2), there This work was partially supported by the University of were no significant differences in their mean body Florida, Department of Entomology and Nematology weight measured on the day nearest to the onset Hatch Project 02362 and by a scholarship to A.R.P. from of oviposition (Table 3). Thus, the slowed weight Empresa Brasileira de Pesquisa Agropecuaria (EMBRA- gain of females on soybean seeds and peanuts (Ta- PA). This article is Fla. Agric. Exp. Stn. Journal Series ble 2) may have contributed to their delayed ovi- No. 5833. position (Table 1). However, oviposition was also delayed on soybean pods and green beans in spite References Cited of weight gain by females on these two foods being similar to weight gain by females on I. hirsuta and AI-Munshi, D. M., D. R. Scott, and H. W. Smith. 1982. Some plant host effects on Lygus hesperus (Hemip- on C. lanceolata. Thus, it appears that both weight tera: Miridae). J. Econ. Entomol. 75: 813-815. gain and the quality of the food being consumed Ananthakrishnan, T. N., K. Raman, and K. P. Sanja- influence the timing of oviposition in P. guildinii. yon. 1982. Comparative growth rate, fecundity In conclusion, the results demonstrate that adults and behavioral diversity of the dusky cotton bug, of P. guildinii exhibit differences in performance Oxycarenus hyalinipennis Costa (Hemiptera: Ly- depending on the food source utilized. Pods of I. gaeidae) on certain malvaceous host plants. Proc. In- hirsuta were the most suitable food, followed by dian Nat. Sci. Acad. 48B: 577-584. pods of C. lanceolata, on which a high percentage Fehr, W. R., C. E. Caviness, D. T. Burmood, and J. S. of females exhibited early oviposition, although fe- Pennington. 1971. Stage of development descrip- tions for soybeans, Glycine max (L.) Merrill. Crop cundity was reduced. Green beans, soybean pods, Sci. 11: 929-931. mature soybean seeds and peanuts were less suit- Hallman, G. 1979. Importancia de algunas relaciones able foods, allowing fewer females to oviposit and naturales plantas-artropodos en la agricultura de la causing delayed oviposition and reduced fecun- zona calida de) Tolima Central. Rev. Colomb. Ento- dity. The nature of the differences in food quality mol. 5: 19-26. (e.g., protein levels, amino acid composition of Harris, V. E., and J. W. Todd. 1981. Rearing the 242 ENVIRONMENTAL ENTOMOLOGY Vol. 14, no. 3

southern green stink bug, Nezara vtridula, with rel- 1985b. New host plant records for the stink bug Pi- evant aspects of its biology. J. Ga. Entomol. Soc. 16: ezodorus guildinli in Florida. Ibid. (in press). 203-210. Panizzi, A. R., and J. G. Smith. 1977. Biology of Kester, K. M., and C. M. Smith. 1984. Effects of diet Piezodorus guildinii: oviposition, development time, on growth, fecundity and duration of tethered flight adult sex ratio and longevity. Ann. Entomol. Soc. of Nezara vtTidula. Entomol. Exp. Appl. 35: 75-81. Am. 70: 35-39. McPherson, J. E. 1982. The (Hemip- Ray, A. A. [ed.]. 1982. SAS user's guide: statistics. tera) of northeastern North America with emphasis Stat. Anal. Syst. Inst., Inc., Cary, North Carolina. on the fauna of Illinois. Southern Ill. Univ. Press, Siansky, F., Jr. 1980a. Quantitative food utilization Carbondale. and reproductive allocation by adult milkweed bugs, Menezes, E. B. 1981. Population dynamics of the Oncopeltus fasciatus. Physiol. Entomol. 5: 73-86. stinkbug (Hemiptera: Pentatomidae) complex on 1980b. Effect of food limitation on food consumption soybean and comparison of two relative methods of and reproductive allocation by adult milkweed bugs, sampling. Ph.D. dissertation, University of Florida, Oncopeltus fasciatus. J. Physiol. 26: 79-84. Gainesville. Villas Boas, G. L., and A. R. Panizzi. 1980. Biologia Miner, F. D. 1966. Biology and control of stink bugs de Euschistus heros (Fabricius 1798) em soja (Gly- on soybeans. Ark. Agric. Exp. Stn. Bull. 708: 1-40. cine max (L.) Merrill). An. Soc. Entomol. Brasil 9: Panizzi, A. R., and D. C. Herzog. 1984. Biology of 105-113. Thyanta perditor (Hemiptera: Pentatomidae). Ann. Entomol. Soc. Am. 77: 646-650. Received for publication 14 September 1984; accept- Panizzi, A. R., and F. Siansky, Jr. 1985a. Review of ed 1 February 1985. phytophagous pentatomids (Hemiptera: Pentatomi- dae) associated with soybean in the Americas. Fla. Entomol. (in press).