Proc. Fla. State Hort. Soc. 91: 250-253. 1978.

RESPONSE OF FLOWER CROPS AND THEIR INSECT PESTS TO THE SYNTHETIC PYRETHROID INSECTICIDE, PERMETHRIN1 James F. Price and David J. Schuster ducted during 1978 (Table 1). All greenhouse and open IFAS, University of Florida, field studies were conducted at the Agricultural Research Agricultural Research & Education Center, and Education Center (AREC) in Bradenton, Fla. With Bradenton, Florida 33508 the exception of Experiment 10 conducted at AREC, all ex periments in a saran house environment (25% shade) were Additional index words, chrysanthemum, African violet, conducted within the facilities of cooperating flower grow exacum, , caladium, carnation, gladiolus, gypsophila, ers. Flower beds in saran houses were 36 inches (91.4 cm) leafminer, , cabbage looper, . wide and those in the field were 32 inches (81.3 cm) wide. Experiments 7,9, and 10 were conducted on beds mulched Abstract. The synthetic pyrethroid insecticide, permethrin with black polyethylene. Beds in all other tests were not (3-phenoxybenzyl (±)-3-(2f2-dichIorovinyl)-2,2-dimethyl = mulched. All treatments appeared once in 4 complete blocks. cyclopropanecarboxylate), formulated as SBP 1513 and Am Pesticidal sprays were applied weekly and notations of bush(R), was evaluated as an insecticidal spray on chrysan phytotoxic reactions were made as the reactions became themum (Chrysanthemum morifolium Ramat.), carnation evident. (Dianthus caryophyllus L.)/ African violet (Saintpaulia ionan- Mines of L. sativae from 10 randomly selected chrysanthe tha Wendl), caladium (Caladium hortulanum Birdsey), episcia mum stems per plot were counted 8 and 9 weeks ('Dignity,' (Episcia cupreata (Hooker) Hans.), exacum (Exacum affine standard) or 9, 10, and 11 weeks ('Darkchip,' pompon) after Balfour), statice (Limonium sinuatum (L.) Mill.), gladiolus initial chemical applications in Experiment 1. Data from (Gladiolus grandiflorus Hort.), gypsophila (Gypsophila pani- all evaluations were totaled for each cultivar and trans culatum L), and poinsettia (Euphorbia pulcherrima Wild.). formed yx + 0.5 before analysis of variance and mean In chrysanthemums treated with permethrin at as low as separation by Duncan's multiple range test. In Experi 0.125 Ib ai/100 gal, populations of chrysanthemum aphid ment 4, leafmines from 25 chrysanthemum leaves ran (Macrosiphoniella sanborni (Gillette)), cabbage looper (Tri- domly selected from the middle 1/3 stratum of stems in choplusia ni Hubner) and its damage, and vegetable leaf- each plot of the2 cultivars were counted 5 and 6 weeks miner (Liriomyza sativae Blanchard) mines were significantly following treatments. Data from those2 evaluation periods reduced below levels that occurred when water alone was were totaled, transformed, and analyzed. Numbers of leaf- applied. Populations of the striped mealybug (Ferrisia vir- mines present and feeding holes of lepidopterous larvae on gata (Cockerel!)) were reduced up to 100%when SBP 1513 10 randomly selected chrysanthemum stems from Experi was applied at 0.125 Ib ai/100 gal to African violets, cala ment 3 were counted at flower harvest. Also evaluated at dium, episcia, and exacum. SBP 1513 was highly toxic to that time were cabbage loopers (Trichoplusia ni (Hubner)), foliage of gypsophila but that formulation and Ambush dis observed in entire plots, and flower thrips (Frankliniella played little phytotoxicity to foliage of the other tritici (Fitch)), collected by the method of Poe and Green evaluated. No phytotoxic reaction to chrysanthemum and (2). In that experiment, chrysanthemum aphid (Macro carnation flowers occurred when SBP 1513 was applied at siphoniella sanborni (Gillette)) populations were deter 0.25 Ib ai/100 gal, but discoloration of flowers occurred in mined 3 weeks after the first appeared on African violet, exacum, and gladiolus. terminals. Entire plots were sampled for aphids and numbers of terminals that hosted more than 5 aphids Many of pyrethrum's benefits, such as rapid action, ex were recorded. cellent activity against adult dipterans, and low acute Caladium tubers infested with striped human hazard became readily available to plant protec (Ferrisia virgata (Cockerell)) were placed onto 2 groups of tionists following the introduction of synthetic pyrethroids. caladium, African violet, episcia, and exacum (Experiments These compounds have a wide spectrum of insecticidal 11-14). SBP 1513 applications were initiated on 1 group of activity, degrade less in ultraviolet light, and cost about plants when mealybugs first began to transfer to their new the same as naturally derived pyrethrums. However, few hosts and to the second group 6 weeks later when plants of these new compounds have been registered for orna were heavily infested. Mealybugs on the 5 most heavily mental plants. Resmethrin is the only synthetic pyrethroid colonized caladium petioles and from all leaves and stems registered for more than one crop. Only in the past year of the other plants in both groups were counted 1 week was ICI, Inc. granted an emergency registration for Am following the last chemical application to the respective bush (R> for vegetable leafminer (Liriomyza sativae Blan group. chard) control in chrysanthemums (Chrysanthemum mori- folium Ramat.). Results and Discussion Previous information indicates that the synthetic py Significantly fewer leafmines were observed on chry rethroidsare effective in management of insect pests santhemums where Ambush was applied at 0.10 and 0.20 common in ornamentals (1, 3, 4). To more accurately assess Ib ai/100 gal than on plants treated with water alone thepotential of permethrin for management of ornamental (Table 2). SBP 1513 controlled leafminers as well as did pest populations, Ambush 2EC and SBP 1513 1 TEC Vydate

250 Proc. Fla. State Hort. Soc. 91: 1978. Table 1. Summary of experiments evaluating the efficacy of 2 permethrin formulations for insect control and phytotoxicity on several orna mental crops.

Expt. Chemicals Lb. ai/ Gal./ No. weekly Insectz Plot Crop no. Crop Cultivar(s) tested 100 gal. acre treatments evaluated size environment

Chrysanthemum: Dignity Ambush O.ly 225 8 Leafminer 8 ft bed Saran house Darkchip 0.2 10 (2.44 m) Vydate 1.0

Chrysanthemum: Golden Polaris Ambush 0.1 225 10 None 8 ft bed Saran house Statesman 0.2 Darkchip 0.4 Yellow Albatross Albatross Yellow Dignity Dignity Promenade Donlope's White Spider Onward Yellow Knight May Shoesmith Fuji Mefo

Chrysanthemum: Yellow Manatee SBP 1513 0.125y 225 7 Chrysanthe 8 ft bed Saran house Iceberg 0.25 mum aphid Cabbage looper Flower thrips Leafminer

4 Chrysanthemum: Yellow Manatee Ambush O.ly 225 5 Leafminer 8 ft bed Saran house Iceberg 0.2

5 Chrysanthemum: Accent Ambush 0.1 225 5 None 8 ft bed Saran hnnse Jackstraw 0.2 Florida Marble 0.4 Beloved Firepower White Marble

Carnation: Starfire SBP 1513 0.125 225 None 4 ft bed Saran house White Elegance 0.25 0.50

Statice: Kampf Js Blue SBP 1513 0.125 75 None 4 ft bed Field 0.25 0.50

Gladiolus: Manatee Rose SBP 1513 0.125 143 None 5 ft bed Field 0.25 0.50

Gypsophila: Bristol Fairy SBP 1513 0.125 122 None 6 ft bed Field 0.25 0.50

10 Gypsophila: Bristol Fairy SBP 1513 0.125 122 None 6 ft bed Saran house 0.25 0.50 Ambush 0.1 0.2

11 Caladiumx: Candidum SBP 1513 0.125 N/A Mealybug 2 pots Greenhouse

12 African violet: Meta SBP 1513 0.125 N/A Mealybug 2 pots Greenhouse

13 Episciax: Acajou SBP 1513 0.125 N/A Mealybug 2 pots Greenhouse Frosty

14 Exacumx Elfin SBP 1513 0.125 N/A 4 Mealybug 2 pots Greenhouse 15 Poinsettia: Annette Hegg Diva SBP 1513 0.125 N/A 6 None 1 pot Greenhouse 0.25 0.50 zPhytotoxic reactions of test plants to each chemical compound and each rate of application were also evaluated. yln addition to those rates indicated, a rate 4 times that of the lowest rate tested was applied as a treatment for phytotoxic evaluation only. xTwo similar tests were conducted-one upon an initially low mealybug population (Group 1) and one upon an initially dense population (Group 2).

Proc. Fla. State Hort. Soc. 91: 1978. 251 Table 2. Total numbers of Liriomyia sativae mines observed in samples In another small plot test on chrysanthemums, SBP from chrysanthemum plots sprayed with 2 insecticides at varying 1513, applied at 0.125 and 0.25 lb ai/100 gal, significantly rates. reduced numbers of leaf mines (Table 3). In that test SBP 1513, even at the lower rate, provided excellent control of Rate the chrysanthemum aphid (97% reduction), and cabbage Expt. (lbs ai/ Avg. mines looper larvae (91% reduction), and reduced numbers of no. Cultivar Treatment 100 gal) per plotz holes in leaves apparently caused by cabbage looper larvae (93% reduction). SBP 1513 had no significant effect on 1 Dignity Water check 37.5a Ambush 0.10 8.3b flower thrips populations. No phytotoxicity occurred on Vydate 1.00 4.3b foliage or flowers of the chrysanthemum cultivars treated Ambush 0.20 3.5b with Ambush or SBP 1513. In greenhouse tests on African violet (Saintpaulia 1 Darkchip Water check 79.3a Ambush 0.10 19.3b ionantha H. Wendl.), caladium (Caladium hortulanum Ambush 0.20 12.5b Birdsey), exacum (Exacum affine Balfour), and episcia Vydate 1.00 10.8b (Episcia cupreala (Hooker) Hans.) for control of the striped

4 Manatee Water check 49.0a mealybug at initially low densities (experiments 11-14) SBP Iceberg Ambush 0.10 8.5b 1513 maintained mealybug populations 94-100% below the Ambush 0.20 4.5b checks (Table 4, Group 1). SBP 1513 reduced mealybug 4 Yellow Water check 47.3a populations by 63-86% after 4 weekly treatments applied Manatee Ambush 0.10 11.3b to the above plants where heavy infestations of the mealy Iceberg Ambush 0.20 5.8b bug had been permitted to develop (Table 4, Group 2). These data indicate that SBP 1513 may more effectively zMeans separation within a column within a cultivar by Duncan's inhibit further advancement of low density mealybug multiple range test. In Experiment V, values reflect sums of mines populations than reduce high density mealybug populations. in leaves of 10 stems over 3 dates ('Darkchip') of 2 dates ('Dignity'). In Experiment 4 values reflect sums of mines in 25- leaves per plot No phytotoxic reactions occurred on foliage or flowers selected at random on each of 2 dates. when 4 or more weekly applications of SBP 1513 were

Table 3. Influence of 2 rates of the synthetic pyrethroid SBP 1513 on control of various insects and their damage to 'Yellow Manatee Iceberg' chrysanthemum. (Expt. 3).

Average insects or damage observed and % control* Cabbage Cabbage Rate Thripsy Aphids* looper larvae^ looper damagev Leafminesv Treatment (lb ai/100 gal) No. % control No. % control No. % control No. % control No. * % control

Check 152.5a — 57.3a 5.3a — 83.5a — 54.5a SBP 1513 0.125 117.5a 23 1.8b 97 0.5b 91 6.0b 93 18.5b 66 SBP 1513 0.25 115.5a 24 0.5b 99 0.5b 91 3.0b 96 19.5b 64 zMeans separation within columns by Duncan's multiple range test. yNumbers/10 flowers. xNumbers of terminals having more than 5 aphids. ^Numbers observed in entire plot. vNumbers of holes (cabbage looper damage) or leafmines/10 stems.

Table 4. Mealybugs (Ferrisia virgata (Cockerell)) observed after 4 applications of the synthetic pyrethroid SBP 1513 at 0.125 lb ai/100 gal to initially low (Group 1) and high populations (Group 2).

Number observed /o Phytotoxic reaction Crop Insect Check SBP 1513* Control Flowers Foliage

Group 1 African violet Mealybugsy 111.3 1.0 99 Slight None Egg sacs 47.0 3.0 94 Caladium Mealybugs 614.5 2.0 100 X None Egg sacs 10.3 0.0 100 Episcia Mealybugs 77.0 4.0 95 None None Egg sacs 30.8 1.5 95 Exacum Mealybugs 15.2 0.5 97 Slight None Egg sacs 15.3 0.5 97

Group 2W African violet Mealybugs 38.2 8.8 77 Caladium Mealybugs 406.7 59.0 85 Episcia Mealybugs 69.0 4.5 94 Exacum Mealybugs 23.7 8.8 63 zln each case, populations subjected to SBP 1513 were significantly lower (P ^ 0.05) than those subjected to water alone (by Duncan's New Multiple Range Test). yValues reflect adult and nymphal mealybugs larger than 2nd instar. xNot observed. wOnly adult and nymphal mealybugs were evaluated in Group 2. 252 Proc. Fla. State Hort. Soc. 91: 1978. applied to 'Starfire' and 'White Elegance' carnations chrysanthemum aphid, and mealybug populations on a wide (Dianthus caryophyllus L.) in a saran house or to 'Kampf's range of ornamental crops and production environments. Blue' statice, (Limonium sinuatum (L.)) Mill, in an open Control of these and other pest populations, little phyto field. Some flower discoloration occurred when SBP 1518 toxicity to ornamental crops, and the relative safety to was applied to open flowers of 'Manatee Rose' gladiolus exposed humans and the environment contribute to an en (Gladiolus grandiflorns Hort.), 'Meta' African violet, and couraging outlook for permethrin use in the ornamental 'Elfin' exacum. In the commercial production of gladiolus, industry. The importance, however, of insecticidal agents flower spikes are harvested when the lowest floret shows in the ornamental industry to selectively reduce pest popu about i/2 inch of exposed petal. SBP 1513 damage to lations while allowing development of beneficial fauna re flowers may not be apparent in commercial gladiolus pro quires that permethrin and other compounds be investi duction. The new array of undamaged African violet and gated thoroughly to develop the best integration procedures. exacum flowers is usually restored within a few days after Through development of precise application timing tech any damage by pesticides to the older flowers and thus, niques, new formulations, etc., permethrin may indeed be hazards from use of this permethrin formulation are mini come an important tool in the management of the arthro mized. Leaves and stems of the African violet, episcia, pods associated with ornamentals. exacum, and caladiums were not damaged by repeated SBP 1513 treatments. However, in 2 tests gypsophila (Gypso- phila paniculatum L.), plants were killed by single appli Literature Cited cations of SBP 1513 at all rates tested (Experiments 9 and 1. Klobe, W. D. and P. L. Lambdin. 1976. Control of whiteflies in 10). Ambush was not phytotoxic to gypsophila. This greenhouses with a new synthetic pyrethroid. Annu. Form Home suggests that the inactive components in the SBP 1513 formu Sci. Prog. Rep. 100:14-15. 2. Poe, S. L. and J. L. Green. 1974. Pest management determinant lation promote the phytotoxicity in gypsophila. Small areas factors in chrysanthemum culture. Proc, Fla. State Hort. Soc. of necrotic tissue occasionally developed in poinsettia 87:467-471. (Euphorbia pulcherrima Wild.) leaves and bracts treated 3. Schuster, D. J., R. B. Workman, R. B. Chalfant, and W. H. Denton. with 0.125 to 0.25 lb permethrin ai/100 gal formulated as 1977. Cabbage looper: Control of cabbage with synthetic pyre- throids and other insecticides. /. Ga. Entomol. Soc. 12(3):228-231. SBP 1513. 4. Waddill, Van H. 1968. Contact toxicity of four synthetic pyrethroids Permethrin, formulated as SBP 1513 and/or Ambush, and methomyl to some adult insect parasites. Fla. Entomol. 61:27- provided reliable control of leafminer, cabbage looper, 30.

Proc. Fla. State Hort. Soc. 91: 253-255. 1978.

ARTHROPODS ASSOCIATED WITH LIGUSTRUAA SINENSE (LOUR.)1

S. L. Poe, S. Burgess and D. Lester environment as a hedge, border or specimen plant (3). Al IFAS, Department of Entomology and Nematology, though both variegated and nonvariegated forms are known, 3103 McCarty Hall, University of Florida, the variegated form is more commonly planted to add color Gainesville, Florida 32611 and design in the landscape (2). Ligustrum tolerates a variety of soil types and conditions. A range of sun, shade, Additional index words. Citrus whitefly, white peach scale, moisture and nutritional conditions are acceptable, al but mite, privet mite, Tumid mite. though under stress from pathogens, nematodes and arthro pods privet often loses its leaves and appears unsightly. Two specimen Ligustrum plants sampled monthly in Abstract. Landscape plantings of Ligustrum sinense 1976-1977 in Gainesville, Florida yielded a total of 22 (Lour.) were sampled in north, central and south Florida in in 10 Acarine families. About 80% of the mites collected 2 studies to determine the kinds of arthropods present, fre were phytophagous, half the number being the tenuipalpid quency, and relative abundance. In the first study more than mite Brevipalpus inornatus (Banks) (1). However, no dam 90% of the 50 plants examined were infested with insects, age symptoms nor plant appearance records were taken mites or both. The most commonly occurring species were during the study. The research here was undertaken to white peach scale Pseudaulacaspis pentagona (Targ.-Tozz.) determine species composition and frequency of arthropods 86%, tenuipalpid mites, Brevipalpus obovatus (Donnadieu) on several plants in landscapes and to determine the rela 36% and Brevipalpus phoenicis (Geijskes) 30%, and spider tive response of the plant to pest abundance. mite Tetranychus tumidus (Banks) 56%. In the second study, white peach scale occurred on 19% of 72 plants in well maintained landscapes. Poor plant appearance was associ Materials and Methods ated with large populations of scales and phytophagous Three basic approaches were used to obtain data con mites in both studies. Other species of mites, scales and cerning arthropods, their relative abundance and plant whiteflies present on Ligustrum were not directly associated damage. Firstly, field collection records and inspection re with plant damage. ports from the Florida State Department of Agriculture and Consumer Services, Division of Plant Industry and records In Florida, Ligustrum sinense (Lour.) also known as of a previous study (1) were examined to obtain a list of Chinese privet (family Oleaceae) is utilized in an outdoor the more prevalent species. Secondly, 50 Ligustrum plants in permanent landscapes iFlorida Agricultural Experiment Stations Journal Series No. 1549. We thank Ms. Gail H. Childs for assistance in the laboratory and Mr. were sampled during September-December 1977 in central H. A. Denmark for assistance in identifying mite species. and south Florida by pruning 10 four-inch (10.16 cm)

Proc. Fla. State Hort. Soc. 91: 1978. 253