Plant Protection Quarterly Vol.10(3) 1995 112 citrus, its selectivity may make it a useful Effect of the insect growth regulator buprofezin pesticide for integrated pest manage- ment. Smith and Papacek (1990) demon- against citrus pests Coccus viridis Green, strated its efficacy against citrus snow scale Unaspis citri (Comstock), and its low Polyphagotarsonemus latus (Banks) and Aonidiella toxicity to the important parasitoids aurantii (Maskell) and the predatory Coccinellid Aphytis lingnanensis Compere in red scale Aonidiella aurantii (Maskell) and Chilocorus circumdatus Gyllenhal Leptomastix dactylopii Howard in citrus mealybug Planococcus citri (Risso). How- D. Smith, Queensland Department of Primary Industries, Box 5083, Sunshine ever, it was moderately toxic to larval Coast Mail Centre, Nambour, Queensland 4560, Australia. stages of Cryptolaemus montrouzieri Mulsant, an important Coccinellid preda- Summary tor of citrus mealybug and the cottony cit- The insect growth regulator buprofezin significantly reduced the progeny of rus scale Pulvinaria polygonata Cockerell. at 0.125, 0.25 and 0.5 g a.i. L -1 was tested adult beetles. This paper described trials testing the with currently used pesticides against The possible role and use of potency of buprofezin against green cof- the south-east Queensland citrus pests buprofezin in integrated pest manage- fee scale Coccus viridis Green, red scale Coccus viridis, Polyphagotarsonemus ment in Queensland citrus is discussed. and broad mite Polyphagotarsonemus latus latus and Aonidiella aurantii and the (Banks), all serious pests in citrus in predatory Coccinellid Chilocorus Introduction Queensland (Smith 1994). Results are also circumdatus. Buprofezin is an insect growth regulator given of toxicity to another Coccinellid, Single applications at 0.125, 0.25 and which inhibits chitin production in juve- Chilocorus circumdatus Gyllenhal. This is 0.5 g a.i. L -1 gave unsatisfactory control nile stages, causing abnormality at moult- an important predator on citrus snow of C. viridis in comparison to 1% oil and ing and subsequently death two to three scale. methidathion at 0.5 g a.i. L -1. All three days after application (Uchida et al. 1985). rates and dicofol at 0.5 g a.i. L -1 effec- It was developed for the control of rice Materials and methods tively controlled P. latus. At 0.125 and plant hoppers, leaf hoppers, white flies, The trial on red scale was conducted in 0.25 g a.i. L -1 buprofezin compared satis- scales and mealybugs (Shibuya 1984, a citrus orchard at Gayndah during factorily with methidathion at 0.5 g a.i. Ishaaya 1992). Buprofezin is selective for February–April 1991. Trials against the L-1 against A. aurantii. It was toxic at 0.5 the Homoptera and harmless to many other insects were conducted at g a.i. L -1 to all larval stages of C. circum- natural enemies (Heinricks et al. 1984, Maroochy Horticultural Research Station, datus and at 0.125 and 0.25 g a.i. L -1 to Garrido et al. 1985). Because of the pre- Nambour during April–June (1992). The first instar larvae. The highest rate dominance of Homopteran pests in following formulations of pesticides were used: buprofezin (400 g L-1) as a flowable Table 1. Effect of treatments on numbers of adult female green coffee scale concentrate, dicofol (225 g L-1) as an on coffee at Maroochy Horticultural Research Station, 1992. emulsificable concentrate, methidathion (400 g L-1) an emulsifiable concentrate, Mean number of live adult scale per terminal mineral oil (Ampol D-C-tron®) (839 g L-1) Post-treatment and hydrated lime. TreatmentA (g a.i. L-1) Pre-treatment 8 days 58 days Trial 1 Buprofezin (0.125) 35.5 a 36.8 c 14.1 d The first trial was on green coffee scale Buprofezin (0.25) 33.9 a 35.4 bc 12.6 cd infesting coffee (Coffee arabica L.) plants Buprofezin (0.5) 44.7 a 33.3 bc 5.3 bc (50–70 cm high) grown singularly in pots Mineral oil (1.00) 41.7 a 10.0 a 3.1 b held in a glasshouse. Temperatures in the Methidathion (0.55) 39.8 a 21.9 b 0.0 a glasshouse varied from 23–30°C and Untreated 47.9 a 66.5 d 103.5 e humidities from 60–90%. Spray were ap- A Treatment applied 1 April 1992. plied with a hand held sprayer using 200 Means in columns followed by the same letter are not significantly different (P=0.05). mL of spray per plant on 1 April. Wetting Log x and log 1 + x transformations used, presented data back-transformed. agent Agral 60® was added to the buprofezin and methidathion treatments. Table 2. Effect of treatments on the percentage of live first and second Assessments were made of the live instar and adult female green coffee scale on coffee at Maroochy adult scale population on 1 April (pre- Horticultural Research Station, 1992. treatment) and again after 8 and 58 days. Counts were made on the terminal 5 cm Mean % live post-treatments (combined) and five attached leaves of one randomly First instar Second instar Adult selected soft twig at the top of each plant Treatment 8/14/29 37/44 8/14/29 37/44 8/14/29 37/44 (Table 1). Assessments were also made of (g a.i. L-1) days days days days days days the percentages of live and dead first instar, second instar and adult scale on Buprofezin (0.125) 38.0 bc 13.6 cd 62.7 b 35.3 bc 29.7 b 26.2 b 1 April (pre-treatment) and again after 8, Buprofezin (0.25) 61.6 c 10.7 c 68.4 bc 22.5 b 31.8 b 28.2 b 14, 29, 37 and 44 days (Table 2). On each Buprofezin (0.5) 42.9 c 3.1 bc 56.2 b 36.3 c 30.7 b 19.8 b occasion in this sample one (two if insuf- Mineral oil 0.3 ab 0.0 a 0.6 a 0.0 a 1.7 a 0.0 a ficient scales were present) scale infested Methidathion (0.5) 7.0 b 1.0 ab 4.8 a 0.0 a 0.0 a 0.0 a leaf was randomly picked per plant and Untreated 67.6 c 44.0 e 84.1 c 99.7 d 91.7 c 47.8 b up to 100 scales of each stage were exam- Means in columns followed by the same letter are not significantly different (P=0.05). ined under a binocular steromicroscope. Arc sine transformation used; presented data back-transformed. Mortality in the oil and methidathion 113 Plant Protection Quarterly Vol.10(3) 1995 treatments occurred shortly after spray L ha-1 spray volume was the minimum es- The same treatments were applied in a application, but mortality in the growth timated to be necessary to wet the trees to similar manner to adult beetles on 27 July. regulator treatments occurred more pro- the point of run-off. The percentage of Four treatments (Table 6) with five repli- gressively as different juvenile stages at- live scales were assessed by examining 20 cates were arranged in a randomized tempted to moult. consecutive scales of each stage on each block. Each replicate was again single of five infested fruit per replicate—a total pumpkin infested with oleander scale. Trial 2 of 100 of each stage per replicate (or 400 The pumpkins were held in 20 × 15 × 15 The second trial was on broad mite infest- per treatment). A count was made on 20 cm tubs with gauze lids. Thirty sprayed ing rough lemon seedlings (20–40 cm February (pre-treatment) and again after beetles were used per tub. The number of high) grown three per pot in the same 14 and 51 days. The percentage of infested live beetles per tub were counted at 1, 3, 6, glasshouse as the first trial. Five treat- fruit was also estimated from 20 fruit ran- 14 and 18 days after treatment. After 18 ments (Table 3) with four replicates were domly selected from each of 10 trees per days the number of early instar larvae (re- arranged in a randomized block; each replicate. Assessments were made on 20 sulting from adult oviposition) per tub replicate was composed of two pots (total February (pre-treatment) and after 51 were counted. of six plants). Sprays were applied with a days (just prior to harvest). hand held sprayer applying 200 mL of Results spray per replicate on 28 May. Wetting Trial 4 agent Agral 60® at 0.3 g a.i. L-1 was added In the fourth trial, buprofezin was tested Trial 1 to each chemical treatment. Numbers of (in a constant temperature room at 25°C Results of the first trial are shown in Ta- live motile stages (nymphs and adults) and 60% RH), on first, second plus third, bles 1 and 2. In Table 1, mineral oil and were counted on five young leaves from and fourth instar C. circumdatus larvae. methidathion were highly effective in re- each replicate on 28 May (pre-treatment) Four treatments (Table 5) with three rep- ducing the populations of green coffee using a ×10 magnification hand-lens and licates were arranged in split plot design scale to 3.1 and 0 adults per terminal re- again after 9, 14 and 21 days. with three age groups of larvae—first, spectively after 58 days. Buprofezin re- second plus third, and fourth instars. A duced the population to 14.1, 12.6 and 5.2 Trial 3 replicate consisted of a single butternut adults per terminal. In Table 2 results The third trial was on red scale on Impe- pumpkin infested with oleander scale were combined for the first three sample rial mandarins, 8 years old, 4 m high, Aspidiotus neri Bouché. The treatments dates 8, 14 and 29 days post treatment and planted at a 7.3 × 3.7 m spacing or 375 were applied to the larvae (held tempo- for the final two sample dates after 37 and trees per hectare. Five treatments (Table rarily in plastic tubs) on 15 April using a 44 days. One hundred per cent mortality 4) with four replicates were arranged in a hand held atomiser. Agral 60® at 0.3 g a.i. of all three stages occurred with oil and randomized block. Replicate size aver- L-1 added to each treatment. The sprayed with methidathion. The effect of bupro- aged 30 trees. A single spray application larvae were then carefully transferred fezin at different rates on the different was made on 20 February 1991 with an with a camel hair brush to the pumpkins ages of scale was not significant. oscillating boom calibrated to apply 5000 (20 first, 20 second or third, and 30 fourth L ha-1. The wetting agent Monsoon® at 0.3 instars per pumpkin). After 33 days the Trial 2 g a.i. L-1 was used with the buprofezin number of larvae reaching adulthood In the second trial, all four chemical treat- and methidathion treatments. The 5000 were recorded. ments reduced the broad mite population to a near zero level nine days after appli- Table 3. Effect of treatments on broad mite on rough lemon seedlings at cation and were still effective after 21 days Maroochy Horticultural Research Station, 1992. (Table 3). Mean number of live mites Trial 3 Post-treatment In the third trial, both buprofezin treat- Treatment (g a.i. L-1) Pre-treatment 9 days 14 days 21 days ments resulted in 5–5.8% of third instar red scale alive after 51 days (in compari- Buprofezin (0.125) 17.2 a 0.6 a 0.3 a 0.4 a son to the untreated 34.8%). 2.6–4.2% of Buprofezin (0.25) 15.7 a 0.2 a 0.5 a 0.6 a fruit were infested after 51 days (in com- Buprofezin (0.5) 19.3 a 0.8 a 0.4 a 0.2 a parison to the untreated 13.4%). Dicofol (0.5) 12.3 a 0.0 a 0.4 a 0.3 a Methidathion had 0% alive after 51 days Untreated 16.6 a 12.2 b 7.1 b 6.2 b and 3.7% of fruit infested (Table 4). Means in columns followed by the same letter are not significantly different (P=0.05). Log x or log 1 + x transformation used, presented data back-transformed. Table 4. Percentage live first, second and third instar female red scale and percentage infested fruit in Imperial mandarins at Gayndah, 1991. Pre-treatment 14 days after treatment At harvest 51 days after treatment Instar Chemical treatment 1 2 3 Infested 1 2 3 1 2 3 Infested (g a.i. L-1) fruit fruit Buprofezin (0.125) 68.9 a 77.5 a 73.8 a 17.4 a 13.4 a 15.1 a 40.6 a 13.5 b 10.2 b 5.8 b 4.2 a Buprofezin (0.25) 60.3 a 68.6 a 74.2 a 10.7 a 13.7 a 10.4 a 43.1 ab 3.4 ab 2.7 ab 5.0 b 2.6 a Hydrated lime (15.0) 57.4 a 74.8 a 80.3 a 17.1 a 50.7 b 62.4 b 59.6 ab 81.2 d 71.2 d 42.0 c 11.2 b Methidathion (0.50) 55.4 a 67.0 a 70.0 a 13.8 a 3.5 a 17.3 a 49.1 ab 0.4 a 0.7 a 0.0 a 3.7 a Untreated 52.0 a 68.7 a 63.9 a 14.0 a 44.1 b 55.5 b 65.2 b 50.6 c 50.8 c 34.8 c 13.4 b Means in columns followed by the same letter are not significantly different (P=0.05). Arc sine transformation used; presented data back-transformed. Plant Protection Quarterly Vol.10(3) 1995 114 Table 5. Effect of buprofezin on larvae of Chilocorus circumdatus at result indicated that buprofezin, espe- Maroochy Horticultural Research Station, 1992. cially at the higher rates, will seriously disrupt C. circumdatus, but the lowest rate Mean % of larvae reaching adulthood should allow some survival. Treatment (g a.i. L-1) First Second/Third Fourth Smith and Papacek (1990) and Ishaaya et al. (1991), showed buprofezin to have Buprofezin (0.125) 24.3 cde 25.0 cde 28.9 cd little effect on important red scale Buprofezin (0.25) 13.2 ef 24.5 cde 28.4 cd parasitoids such as A. lingnanensis and Buprofezin (0.5) 3.3 g 16.2 def 6.1 fg Comperiella bifasciata Howard, and on Untreated 53.3 a 48.4 ab 32.2 bc L. dactylopii from citrus mealybug. When Means followed by the same letter are not significantly different (P=0.05). red scale infestations threaten early varie- Arc sine transformation; presented data back-transformed. ties in late summer (with time against parasitoids giving control before harvest), Table 6. Effect of buprofezin on the survival and fecundity of adult buprofezin could be useful in selectively Chilocorus circumdatus at Maroochy Horticultural Research Station, 1992. checking the scale without affecting the parasitoids. Mean %A alive Mean No.B of larvae produced Smith and Papacek (unpublished De- Treatment 18 days after Total 18 days Per surviving adult cember 1992) have also found buprofezin -1 (g a.i. L ) treatment after treatment per day 0.125 g a.i. L-1 to be effective against the Buprofezin (0.125) 48.9 ab 145.0 ab 0.8 ab citrus jassid Empoasca smithi Fletcher and Buprofezin (0.25) 44.7 ab 104.0 bc 0.9 ab Donaldson on maturing navel oranges Buprofezin (0.5) 27.4 b 37.0 c 0.3 b and Imperial mandarins in March and Untreated 59.3 a 218.0 a 1.2 a April. It currently would be useful in Queensland to control both red scale and Means within columns followed by the same letter are not significantly different the citrus jassid. Toxicity to Coccinellids (P=0.05). is an significant negative factor especially A Arc sine transformation. as the two species tested to date, B Log x transformation, presented data back-transformed. (C. montrouzieri and C. circumdatus) are both vital biocontrol agents. Buprofezin Trial 4 Saissetia oleae (Oliver) and Menzel et al. should then be used sparingly not more In the fourth trial, percentages of 1991 showed it to be effective against cot- than once or twice per season and C. circumdatus larvae reaching adulthood tony cushion scale Icerya purchasi avoided where there is heavy activity by are shown in Table 5. Buprofezin at all (Maskell) and citrus mealybug Coccinellids. three rates significantly affected first and Planococcus citri (Rosen). second/third instar (in comparison with Buprofezin gave effective control at Acknowledgments the untreated). The highest rate 0.5 g a.i. 0.125, 0.25 and 0.5 g a.i. L-1 of broad mite The help of Burnside High School stu- L-1 also significantly affected fourth instar and should prove a safe and selective con- dents A. McNichol and N.J. Smith, and of larvae. Table 6 shows the effect of trol for this mite especially in glasshouses. Mr. D.F. Papacek, citrus consultant, buprofezin on adults and on the number Buprofezin was effective at 0.125 and Mundubbera is gratefully acknowledged. of progeny produced by the survivors. 0.25 g a.i. L-1 against red scale. However, Buprofezin at 0.5 g a.i. L-1 induced signifi- the initial scale infestation (11–18% of References cant adult mortality in comparison to the fruit infested at spraying) was moderate Garrido, A., Beitia, F. and Gruenholz, P. untreated. Over 18 days, surviving beetles and a double application as for citrus (1985). Incidence of the growth regula- produced an average 218 larvae signifi- snow scale (Smith and Papacek 1990) may tor NNI-750 on the immature stages of cantly more than the 104 and 37 produced be necessary against heavy infestations. Encarsia formosa Gahan and Cales noacki by the two higher-rates of buprofezin. Ishaaya et al. (1992) achieved best results How. (Hymenoptera: Aphelinidae). Larvae in the untreated (after 18 days) in- against red scale with a double applica- Anals INIA, Agricola 28, 137-45. cluded all four instars but in treatments tion of 0.0625 g a.i. L-1 in combination Grout, T.G. and Richards, G.I. (1991). Ef- such as buprofezin 0.5 g a.i. L-1 only first with 0.5% mineral oil. Single applications fect of buprofezin application at differ- and second. Examination of the scale without oil especially using the wettable ent phenological times on California showed no oviposition by beetles treated powder formulations were inadequate. red scale (Homoptera: Diaspididae). at the two higher rates for 8–10 days. Grout and Richards (1991) also supported Journal of Economic Entomology 84, Data in the four trials was analysed by the use of 0.5% mineral oil in combination 1802-5. one way ANOVA. An arc sine transfor- with buprofezin 0.05 g a.i. L-1 and empha- Heinricks, E.A., Basilio, R.P. and Valen- mation was used on percentages and log sised the need to time application care- cia, S.L. (1984). Buprofezin, a selective x or log 1 + x on numbers; differences fully to have maximum effect on crawler insecticide for the management of were established using Duncan’s multiple populations. Yoran et al. (1988) also rice plant hoppers (Homoptera: range test. The presented data was back- showed a reduction of 20% in crawler Delphacidae) and leaf hoppers transformed and letters used to show dif- production in red scale reproducing fe- (Homoptera: Cicadelliade). Environ- ferences. males from exposure to buprofezin 0.1– mental Entomology 13, 515-31. 0.5 g a.i. L-1. Ishaaya, I. (1992). Selective insect control Discussion Buprofezin at all three rates caused sig- agents—mechanisms and agricultural One application of the buprofezin treat- nificant mortality to larval stages of importance. In ‘Mechanisms of action ments gave unsatisfactory control of C. circumdatus, and reduced egg produc- and resistance’, eds. D. Otto and B. green coffee scale and there were no sig- tion by the adults. Most likely this re- Webber, pp. 127-33. (Intercept, nificant differences in efficacy between sulted from temporary sterilization for Andover, England). the rates of buprofezin used. Yoran et al. 8–10 days as evidenced by an absence of Ishaaya, I., Mendel, Z. and Blumberg, D. (1988) found buprofezin 0.125 and 0.25 g eggs for this period or larva older than the (1992). Effect of buprofezin on Califor- a.i. L-1 to be active against black scale second instar after 18 days. The overall nia red scale, Aonidiella aurantii 115 Plant Protection Quarterly Vol.10(3) 1995 (Maskell) in a citrus orchard. Israel Jour- nal of Entomology 25-6, 67-71. Menzel, A., Blumberg, D. and Ishaaya. (1991). Effect of buprofezin on Icerya purchasis and Planococcus citris. Phytoparasitica 19, 124-33. Shibuya, M. (1984). Applaud a new selec- tive insecticide. Japan Pesticide Informa- tion 44, 17-21. Smith, D. and Papacek, D.F. (1990). Buprofezin: an effective and selective insect growth regulator against Unaspis citri (Hemiptera: Diaspididae) on citrus in south-east Queensland. General and Applied Entomology 22, 25-8. Smith, D. (1994). Citrus. In ‘Managing in- sects and mites in horticultural crops’, eds. E.J. Brough, R.J. Elder and G.H. Beavis, pp. 49-67. (Queensland Depart- ment of Primary Industries Information Series Q 1941010). Uchida, M., Asia, T. and Sugimot, T. (1985). Inhibition of cuticle deposition and chitin biosynthesis by a new insect growth regulator, buprofezin in Nilaparvata lugens Stal. Agricultural and Biological Chemistry 49, 1233-4. Yarom, I., Blumberg, D. and Ishaaya, I. (1988). Effects of buprofezin on Califor- nia red scale (Homoptera: Diaspididae) and Mediterranean black scale (Homoptera: Coccidae). Journal of Eco- nomic Entomology 81, 1581-5.