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Effect of the Insect Growth Regulator Novaluron

Effect of the Insect Growth Regulator Novaluron

egg viability compared to the un- reduction in egg viability or eggs fail to Effect of the treated control based on live nymphal hatch. This effect is greatest on young Growth Regulator counts 8 DAT. In Expt. 2, both rates adult female whitefl ies that are treated of novaluron signifi cantly reduced egg (Asia et al., 1985) coinciding with the viability compared to the untreated development of the oocyte, which may Novaluron control, based on live nymphal counts and number of dead eggs 8 DAT. effect cuticle formation of maturing (Pedestal) on The results from this study indicate eggs (Asai et al., 1985). that novaluron negatively affected The no- Silverleaf Whitefl y female silverleaf whitefl y reproduc- valuron (Pedestal; Crompton Uniroyal tion by reducing egg viability, which Chemical, Middlebury, Conn.), which Reproduction may decrease the number of silverleaf is a synthesis inhibitor, has activity whitefl ies produced during a cropping on the eggs and larvae of sweet potato cycle. This is an important long-term whitefl y ( tabaci) (Ishaaya et al., Raymond A. Cloyd, management strategy that may 1996). However, minimal information reduce the number of ap- 1 is available on the effect of novaluron Stephen R. Keith , and plications and decrease labor costs. on silverleaf whitefl y, which is the pri- Cindy L. Galle1 mary whitefl y species in greenhouses, ilverleaf whitefl y is a major insect particularly on (Euphorbia pest on ornamental plants grown pulcherrima) (Lindquist, 1990). As a ADDITIONAL INDEX WORDS. silverleaf in greenhouses, and is primarily whitefl y, novaluron, insect growth S result, the objective of this study was to regulator, greenhouse, fl oriculture, managed using systemic determine if novaluron affects silverleaf egg viability such as (Marathon; Olym- whitefl y reproduction by inhibiting pic Horticultural Products, Bradenton, egg viability. SUMMARY. Insect growth regulators, Fla.) and insect growth regulators which are primarily used to kill the (Lindquist, 1998). Insect growth Materials and methods larval stages of certain insect groups, have indirect effects on the adult stage regulators may be placed into two EXPT. 1. The following procedure of whitefl ies. In this study, we assessed general categories: was used to infest plants with silverleaf the effect of the insect growth regula- mimics or analogs, and chitin synthe- whitefl y. Silverleaf whitefl y popula- tor novaluron (Pedestal) on the repro- sis inhibitors (Olkowski et al., 1991; tions were maintained on poinsettia duction of silverleaf whitefl y (Bemisia Ware, 2000). Juvenile hormone mimics and transvaal daisy plants enclosed in argentifolii). Two experiments were interfere with insect development and an infestation chamber. The silverleaf conducted by exposing adult female prevent from completing their whitefl ies were originally obtained silverleaf whitefl ies to the low [0.47 lifecycle. As a result, insects either fail from Bohn Nursery (Collinsville, Ill.) mL.L–1 (6 fl oz/100 gal)] and high . –1 to reach adulthood because they die as and Keith Nursery (Marissa, Ill.), and [0.63 mL L (8 fl oz/100 gal)] label- immatures, or they mature into sterile recommended rates of novaluron. were identifi ed as silverleaf whitefl y There was also an untreated control. adult females (Medina et al., 2003). based on morphological characteristics Infested plants [mist fl ower (Eupa- Chitin synthesis inhibitors infl uence the (Dreistadt, 2001). The enclosed cham- torium coelenstinum) and transvaal insect’s ability to molt by inhibiting the ber was 2 m wide × 5 m long (6.6 × 16.4 daisy (Gerbera jamesonii) for Expt. 1 formation of chitin, which is an essential ft), with an A-frame roofl ine measuring and Expt. 2, respectively] containing component of an insect’s exoskeleton. 142 cm (55.9 inches) at point with the adult female silverleaf whitefl ies were Insects die while molting from one sides 91 cm (35.8 inches) high. There sprayed with novaluron using a car- stadium to the next (Olkowski et al., was a single wire-mesh bench inside the bon dioxide (CO ) backpack sprayer. 2 1991; Ware, 2000). chamber. The bench height from the Plants were immediately placed into Although insect growth regula- fl oor was 91 cm. The roof and ends cages covered with antivirus insect tors generally are only effective on screening. After 24 hours, six adult fe- were covered with clear 8-mm (0.31 male silverleaf whitefl ies were aspirat- the larval or nymphal stages of insects inch) corrugated polycarbonate, and ed from the treated plants, and immo- (Ware, 2000), studies have shown that the sides and bottom were covered insect growth regulators can indirectly with antivirus insect screening 50 × bilized with CO2 before being placed onto untreated plants [transvaal daisy affect the adult stages by reducing 24 [0.2 × 0.8 mm (0.008 × 0.031 for Expt. 1, and rose-of-china (Hibis- reproductive capacity or egg viability inch); Greentek, Edgerton, Wis.]. The cus rosa-sinensis) for Expt. 2]. Three (Nassar et al., 1972). Egg viability is sides were rolled up and secured with munger cells containing two adult one way to assess reproduction, and Velcro when closed. Poinsettia and female silverleaf whitefl ies per cell may be defi ned as those eggs that transvaal daisy plants, obtained from were attached to leaves of each of the hatch into live nymphs or larvae. Sev- H.M. Buckley and Sons (Springfi eld, untreated plants. The number of live eral studies have evaluated the effects and dead eggs, and live nymphs per Ill.) and Earl J. Small Growers (Pinellas plant was assessed 4 and 8 days after of insect growth regulators, such as Park, Fla.) were rotated and replaced treatment (DAT). In Expt. 1, the low (Ishaaya and Horowitz, with healthy plants approximately ev- rate of novaluron signifi cantly reduced 1995) and ( Asai et al., ery 2 weeks to maintain the silverleaf 1985; Yasui et al., 1987), on the vi- whitefl y colony. ability of whitefl y eggs. These studies Mist fl ower plants to be infested Department of Natural Resources and Environmental have found that when adult female with silverleaf whitefl ies were approxi- Sciences, University of Illinois, Urbana, IL 61801. whitefl ies are directly sprayed with mately 25 cm (9.8 inches) high when 1AllTech Research and Development, Sparta, IL 62286. insect growth regulators, there is a they were transplanted into 1.8-L

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(0.48 gal) containers in a growing diameter, with a mesh screen on the present 4 and 8 DAT following place- medium (MetroMix 700; Scotts Co., end inserted into the vacuum com- ment on untreated plants (transvaal Marysville, Ohio) containing 50% to ponent, and a 15-cm- (5.9 inches) daisy). This procedure of assessing egg 60% composted pine bark, 20% to 30% long tube with a 0.9-cm (0.35 inches) viability based on nymphal counts has Canadian sphagnum peat moss, 5% to opening that was connected to a been used in previous studies (Asai et 15% medium grade horticultural ver- rubber fi tting on the opposite end. al., 1985). miculite, and 5% to 15% horticultural Silverleaf whitefl ies were immobilized EXPT. 2. This experiment was

perlite. The plants were top-dressed by exposing them to 75% CO2 for 4 conducted in the same manner as Expt. after planting with 5 g (0.2 oz) of s. Three munger cells (Robb, 1989) 1 except that the plants initially infested 14N–6.1P–11.6K Osmocote (Scotts containing two adult female silverleaf with silverleaf whitefl y were transvaal Co.) granular fertilizer. None of the whitefl ies per cell were attached to daisy, and the untreated plants on plants used in this experiment had the leaves of the separate group of 21 which adult female silverleaf whitefl ies been previously treated with a systemic untreated transvaal daisy plants. The were placed was rose-of-china. Similar insecticide or insect growth regulator. munger cells were attached to the top to Expt. 1, none of the plants used in Three days after transplanting, 21 mist of the leaf and secured at each of four this experiment had been previously fl ower plants were placed into the in- corners by twist ties. All test plants treated with a systemic insecticide or festation chamber in order to become were held in a laboratory set at 25 °C insect growth regulator. Different plant infested with silverleaf whitefl ies. Ad- (± 4 °C) [77.0 °F (± 7.2 °F)], 50% to species were used in this experiment ditionally, 21 separate transvaal daisy 60% relative humidity (RH), with 16 due to availability of plant material. plants grown under similar conditions h light/8 h dark photoperiod. Plants All data were analyzed in a com- were left un-infested to serve as hosts were irrigated as needed with a hand- pletely randomized design using a one- for the treated female silverleaf white- held sprinkler. way ANOVA (SAS Institute, 2002). fl ies (described below). Based on daily The experiment was set up in a Treatment means for the number of live observations of silverleaf whitefl y adults completely randomized design with eggs laid by the adult female silverleaf emerging from pupae in the infestation three treatments and seven replicate whitefl ies, based on pooling the data chamber, we allowed the mist fl ower untreated plants per treatment with from all three munger cells, provided plants to remain in the chamber for three munger cells per plant. There the number of live eggs and live nymphs 7 to 10 d to obtain adult silverleaf were a total of 21 untreated plants with per plant. This was used to determine whitefl ies that were similar in age. six adult female silverleaf whitefl ies per egg viability. All signifi cant treatment Once the plants were infested with a plant. The number of live eggs laid by means were separated using a Fisher’s moderate silverleaf whitefl y population the adult female silverleaf whitefl ies and protected LSD test at P ≤ 0.05. As with (range: 25 to 50 per plant), each plant number of live nymphs per munger Expt. 1, we determined egg viability by was removed from the chamber and cell was assessed 4 and 8 DAT using a counting the number of live nymphs sprayed with one of three treatments. dissecting microscope. Hatched eggs that were present 4 and 8 d following The treatments were the low and high were not counted. Silverleaf whitefl y placement on rose-of-china plants. In label-recommended rates of novaluron eggs were determined to be alive addition, the number of dead eggs (Pedestal; Crompton Uniroyal Chemi- based on color and appearance. Live was assessed. Silverleaf whitefl y eggs cal) at 0.47 and 0.63 mL.L–1, and an eggs were golden-yellow in color, and that were considered dead had brown untreated control. were not shriveled or shrunken. The edges, and were shrunken and shriveled Both the upper and lower leaf edge of the munger cell was slightly in appearance. surfaces of each plant were thoroughly raised on one side from the upper leaf sprayed with a fi ne mist to ensure that surface to prevent the two silverleaf Results all the silverleaf whitefl ies present on whitefl ies from escaping during the 4 EXPT. 1. There were no signifi cant each plant had been in contact with DAT reading. Adult female silverleaf differences among the treatments for the spray solution. Applications were whitefl ies were confi ned in the munger the number of live silverleaf whitefl y

made using a CO2 backpack sprayer cells for 8 d. eggs (F = 0.47; df = 2, 20; P = 0.63) [275.8 kPa (40 psi); fl at fan nozzle- All data were analyzed using SAS or the number of silverleaf whitefl y 8002; 378.5 L.min–1 (100 gal/min)]. Systems for Windows, version 8.0, nymphs (F = 0.31; df = 2, 20; P = 0.73) After the appropriate treatments had in a completely randomized design 4 d after being placed onto untreated been made, each replicate (plant) was using a one-way analysis of variance plants (Table 1). After 8 d on untreated individually placed into a vegetable (ANOVA) (SAS Institute, 2002). plants, there was no signifi cant differ- cage [30 cm diameter base × 76 cm Treatment means for the number of ence among the treatments for the height (11.8 × 29.9 inches, respec- live eggs laid by adult female silverleaf number of live eggs (F = 2.63; df = tively)] covered with antivirus insect whitefl ies, based on pooling the data 2, 20; P = 0.11); however, there was screening 50 × 24 (Greentek) from all three munger cells, provided a signifi cant difference in the number Twenty-four hours after treat- the number of live eggs and live nymphs of live nymphs (F = 4.40; df = 2, 20; P ments had been made, six adult female per plant. This data was used to de- = 0.036) (Table 1). Signifi cantly fewer silverleaf whitefl ies were aspirated from termine egg viability. All signifi cant nymphs emerged (4.0 ± 1.9; mean ± each treated replicate plant using a treatment means were separated using SE) from eggs laid by female silverleaf battery-operated vacuum (Hausherr’s a Fisher’s protected least signifi cant whitefl ies treated with the low label rate Machine Works, Toms River, N.J.). difference (LSD) test at P ≤ 0.05. Egg of novaluron (0.47 mL·L–1) compared The vacuum was fi tted with a 5-cm viability was measured by counting to eggs laid by female adult silverleaf (2.0 inches) vial, 3 cm (1.2 inches) in the number of live nymphs that were whitefl ies treated with the high label

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OOct2004HT.indbct2004HT.indb 555252 99/15/04/15/04 112:31:102:31:10 PPMM rate of novaluron (0.63 mL·L–1) and than untreated silverleaf whitefl ies dum). However, studies have shown untreated silverleaf whitefl ies (Table (Table 2). that when adult female greenhouse 1). Although there was not a signifi - Although we did not assess the whitefl ies (Trialeurodes vaporariorum) cant difference in the number of live number of dead eggs for Expt. 1, we come into direct contact with sprays nymphs between the high label rate of did for Expt. 2, where the number of or wet residues, they lay non-viable novaluron and the untreated control, dead eggs was signifi cantly different eggs or eggs fail to hatch (Yasui et there was a substantial numerical dif- among the treatments (F = 19.39; df = al., 1985). In our study, based on ference (Table 1). 2, 20; P = 0.0002) 8 d after exposure to the number of live nymphs for both EXPT. 2. As with Expt. 1, there novaluron. Female silverleaf whitefl ies experiments, and the number of dead were no signifi cant differences in the treated with the high rate of novaluron eggs in Expt. 2, it appears that adult number of live eggs (F = 0.40; df = (0.63 mL·L–1) had the highest number female silverleaf whitefl ies that were 2, 20; P = 0.68) and number of live of dead eggs compared to female sil- treated with novaluron laid non-viable nymphs 4 d after female silverleaf verleaf whitefl ies treated with the low eggs although not all the eggs were whitefl ies were placed onto rose-of- rate of novaluron (0.47 mL·L–1) and non-viable based on the presence of china plants (Table 2). Additionally, untreated female silverleaf whitefl ies live nymphs. The fact that not all the there was no signifi cant difference in (Table 2). Both treatment levels had eggs laid were non-viable may be that the number of live eggs laid by female signifi cantly more dead eggs than the the insect growth regulator did not silverleaf whitefl ies treated with both untreated silverleaf whitefl ies, which affect the more mature oocytes. label rates of novaluron (F = 2.35; df had no dead eggs (Table 2). The reason that fewer nymphs = 2, 20; P = 0.13) 8 d after female were counted on d 4 for both experi- silverleaf whitefl ies were placed onto Discussion ments is that silverleaf whitefl y eggs rose-of-china plants; however, the Insect growth regulators are pri- typically hatch in 7 to 10 d, depending number of eggs that hatched into marily used on the immature stages on temperature (Mahr et al., 2001). nymphs was signifi cantly different (F of a number of interior plantscape Both experiments were terminated = 4.64; df = 2, 20; P = 0.032), as the insect pests, including citrus mealy- after 8 d, which is within the range adult female silverleaf whitefl ies treated bug (Planococcus citri), long-tailed of egg hatching for silverleaf whitefl y; with both rates of novaluron had sig- mealybug (Pseudococcus longispinus), however, it is possible that this was nifi cantly fewer live nymphs present and brown soft scale (Coccus hesperi- not enough time to allow all the eggs to hatch. In addition, the novaluron Table 1. Mean ± SE number of live eggs and live nymphs of silverleaf whitefl y treatments may have exhibited delayed (Bemisia argentifolii) on transvaal daisy (Gerbera jamesonii) plants 4 and 8 d eclosion, resulting in nymphs hatching after treatment (DAT) with novaluron at both the low and high label-recom- later than the untreated control. mended rates, and an untreated control for Expt. 1. Insect growth regulators suppress No. live No. live reproduction by blocking endocrine Ratez whitefl y eggs whitefl y nymphs secretion or inhibit chorion ovary Treatment n (mL·L–1) DATy (mean ± SE) (mean ± SE) formation (Asai et al., 1985). For example, pyriproxyfen is active as an ± x ± Novaluron 7 0.47 4 89.1 12.7 a 3.5 1.9 a ovicide, larvicide, and has been shown ± ± Novaluron 7 0.63 4 76.1 8.6 a 4.8 1.3 a to sterilize female greenhouse white- ± ± Untreated control 7 ------72.8 13.4 a 5.7 2.4 a fl ies, with activity highest on young ± ± Novaluron 7 0.47 8 96.4 12.0 a 4.0 1.9 b eggs that are 1- to 2-d-old (de Vogue, ± ± Novaluron 7 0.63 8 77.6 5.8 a 7.3 2.8 ab 1999). This insect growth regulator is ± ± Untreated control 7 ------61.0 11.1 a 17.4 5.2 a a potent suppressor of embryogenesis, zLow rate of novaluron = 0.47 mL·L–1 (6.0 fl oz/100 gal) and high rate of novaluron = 0.63 mL·L–1 (8.0 fl as female greenhouse whitefl ies treated oz/100 gal). yDAT = days after treatment. with pyriproxyfen laid non-viable eggs xMeans within a DAT not followed by a common letter are signifi cantly different (P = 0.05) as determined by (Ishaaya and Horowitz, 1995). Fisher’s protected least signifi cant difference (LSD) test P ≤ 0.05. Buprofezin, another insect growth

Table 2. Mean ± SE number of live eggs, dead eggs, and nymphs of silverleaf whitefl y (Bemisia argentifolii) on rose-of-china (Hibiscus rosa-sinensis) plants 4 and 8 d after treatment (DAT) with novaluron at both the low and high label-recommended rates, and an untreated control for Expt. 2. No. live No. dead No. live Ratez whitefl y eggs whitefl y eggs whitefl y nymphs Treatment n (mL·L–1) DATy (mean ± SE) (mean ± SE) (mean ± SE) Novaluron 7 0.47 4 58.7 ± 20.5 ax 0.0 ± 0.0 a 0.0 ± 0.0 a Novaluron 7 0.63 4 56.4 ± 8.4 a 0.0 ± 0.0 a 0.0 ± 0.0 a Untreated control 7 ------39.3 ± 17.1 a 0.0 ± 0.0 a 0.0 ± 0.0 a Novaluron 7 0.47 8 44.6 ± 15.4 a 10.4 ± 3.2 a 1.7 ± 1.1 b Novaluron 7 0.63 8 34.1 ± 7.0 a 21.3 ± 3.5 b 1.0 ± 0.5 b Untreated control 7 ------13.9 ± 6.3 a 0.0 ± 0.0 c 25.4 ± 11.0 a zLow rate of novaluron = 0.47 mL·L–1 (6.0 fl oz/100 gal) and high rate of novaluron = 0.63 mL·L–1 (8.0 fl oz/100 gal). yDAT = days after treatment. xMeans within a DAT not followed by a common letter are signifi cantly different (P = 0.05) as determined by Fisher’s protected least signifi cant difference (LSD) test P ≤ 0.05

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regulator, has activity on both eggs and did not count the number of dead Ishaaya, I., S. Yablonski, Z. Mendelson, Y. adults, with sweet potato whitefl y eggs for Expt. 1, the results from both Mansour, and A.R. Horowitz. 1996. No- females treated with buprofezin lay- experiments are similar and indicate valuron (MCW-275), a novel benzoylphenyl urea, suppressing developing stages of lepi- ing eggs that fail to hatch. However, that, based on live silverleaf whitefl y dopteran, whitefl y and leafminer pests. Proc. treating adult insects with buprofezin nymphs, the insect growth regulator Intl. Conf: Pests and Dis., vol. 3:1013–1020. has a greater effect on egg viability negatively affected egg viability. Brighton Crop Protection Conf., Brighton, than treating eggs directly (Asai et al., The fact that insect growth regu- U.K. 1983). For example, adult sweet potato lators indirectly affect the adult stages Ishaaya, I. and A.R. Horowitz. 1995. whitefl ies in contact with buprofezin- of certain insect species is important in Pyriproxyfen, a novel insect growth regula- treated (Lycopersicon esculen- regard to , as this means tor for controlling whitefl ies: Mechanisms tum) leaves for more than 24 h laid that another developmental life stage and resistance management. Sci. eggs that failed to hatch (Yasui et al., is negatively affected. Suppressing 43:227–232. 1987). This indicates that buprofezin reproduction by treating adult female Lindquist, R.K. 1998. Integrated insect enters the insect body and reduces egg silverleaf whitefl ies is an important and mite management on . Ohio viability by affecting the ovaries (Asai long-term pest management strategy. Florists’ Bul. 825:19–22. et al., 1983; Yasui et al., 1987). (Yasui et al., 1987). Fewer eggs will Lindquist, R.K. 1990. Insect control, p. The insect growth regulator hatch into nymphs, resulting in popu- 46–54. In: Tips on growing poinsettias, 2nd difl ubenzuron has a mode of activity lations taking longer to build up to ed. Ohio Coop. Ext. Serv., Ohio State Univ., similar to buprofezin and may also damaging levels; thus providing green- Columbus. impact whitefl y reproduction by dis- house producers more time to deal with Mahr, S.E.R., R.A. Cloyd, D.L. Mahr, and turbing endocuticle deposition and silverleaf whitefl y infestations. C.S. Sadof. 2001. Biological control of insects inhibiting normal cuticle formation This study is signifi cant to green- and other pests of greenhouse crops. North (Hajjar and Casida, 1978). In fact, both house producers because the results Central Reg. Publ. 581. Univ. of Wisconsin difl ubenzuron and novaluron have a demonstrate that the insect growth Coop. Ext, Madison. similar chemical structure, same mode regulator novaluron, which is active Medina, P., G. Smagghe, F. Budia, L. Tirry, of activity, and are in the same chemical on the nymphal stage of silverleaf and E. Vinuela. 2003. and absorption family, (Thomson, 2001). whitefl ies, also negatively affects female of azadirachtin, difl ubenzuron, pyriproxyfen, However, novaluron is relatively new silverleaf whitefl y reproduction by re- and after topical application in and minimal information is available ducing egg viability. This can decrease predatory larvae of (Neu- roptera: ). Environ. Entomol. on how it affects silverleaf whitefl y the number of whitefl ies that occur 32:196–203. reproduction. during a cropping cycle. As a result, Any differences observed in the fewer insecticide applications may be Nassar, S.G., G.B. Staal, and N.I. Armanious. number of eggs laid between Expt. 1 needed, which may reduce insecticide 1972. Effects and control potential of insect growth regulators with juvenile hormone and Expt. 2 may have been due to plant and labor costs, and avoid worker ex- activity on greenbug. J. Econ. Entomol. type (transvaal daisy vs. rose-of-china) posure to insecticide residues. 66:847–850. or the age of the whitefl ies in the colony. However, insect growth regulators Olkowski, W., S. Daar, and H. Olkowski. Literature cited 1991. Common sense pest control. Taunton have been shown to reduce egg viability Press, Newton, Conn. regardless of the age of female whitefl ies Asai, T., O. Kajihara, M. Fukada, and S. Maekawa. 1985. Studies on the mode of Robb, K.L. 1989. Analysis of Frankliniella (Asai et al., 1985). Furthermore, the action of buprofezin II. Effects on reproduc- results are similar across experiments, occidentalis (Pergande) as a pest of fl oricultural tion of the brown planthopper, Nilaparvata crops in greenhouses. PhD Diss., despite the different plant types used, lugens Stal (Homoptera: Delphacidae). Appl. Univ. of California, Riverside. Diss. Abstr. in that the number of eggs laid by Entomol. Zoolog. 20:111–117. No. 9002637. female silverleaf whitefl ies, and treated Asai, T., M. Fukuda, S. Maekawa, K. Ikeda, with the low rate of novaluron in Expt. SAS Institute, Inc. 2002. SAS Systems for and H. Kanno. 1983. Studies on the mode Windows, version 8.0. SAS Inst., Cary, 1 that hatched into nymphs 8 DAT, of action of buprofezin. I. Nymphcidal and N.C. were signifi cantly less than untreated ovicidal activities on the brown rice planthop- silverleaf whitefl ies (Table 1). More- per, Nilaparvata lugens Stal. (Homoptera: Thomson, W.T. 2001. Agricultural chemi- over, for Expt. 2, the number of eggs Delphacidae). Appl. Entomol. Zoolog. cals book I: Insecticides. Thomson Publ., 18:550–552. laid by female silverleaf whitefl ies, and Fresno, Calif. treated with the low and high rate of de Vogue, E. 1999. Admiral, a new insecticide Ware, G.W. 2000. The pesticide book. Free- novaluron that hatched into nymphs for the control of aleyrodid on tomatoes. Proc. man, San Francisco. 8 DAT, were signifi cantly and numeri- 5th Intl. Conf. Pests and Agr., Montpellier, France. Part I:185–190. Yasui, M., M. Fukada, and S. Maekawa. 1987. cally less than silverleaf whitefl ies that Effects of buprofezin on reproduction of the were untreated (Table 2). In fact, for Dreistadt, S.H. 2001. Integrated pest man- greenhouse whitefl y, Trialeurodes vaporario- Expt. 1 (8 DAT) there were 77% and agement for fl oriculture and nurseries. Univ. rum (Westwood) (Homoptera: Aleyrodidae). 58% fewer nymphs in the low and high of California Statewide Integrated Pest Mgt. Appl. Entomol. Zoolog. 22:266–271. Project, Univ. of California Div. of Agr. and rates of novaluron, respectively, relative Natural Resources Publ. 3402. Yasui, M., M. Fukada, and S. Maekawa. 1985. to the untreated control. Likewise, in Effects of buprofezin on different develop- Expt. 2 (8 DAT) there were 93% and Hajjar, N.P. and J.E. Casida. 1978. Insecti- mental stages of the greenhouse whitefl y, 96% fewer nymphs for the low and cidal benzoyphenylurea: Structure–activity Trialeurodes vaporariorum (Westwood) relationships as chitin synthesis inhibitors. (Homoptera: Aleyrodidae). Appl. Entomol. high rates of novaluron, relative to Science 200:1499–1500. Zoolog. 20:340–347. the untreated control. Although we

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