Challenges for Adoption of Integrated Pest Management (IPM): the Soybean Example.

Soybean is considered one of today's most important crops. Planted on millions of hectares worldwide, the management of soybean pests usually requires large amounts of chemicals. However, a key component to meet the increasing demand for food due to the rapidly growing global population is protecting crops from pests while maintaining environmental quality through ecologically and economically sound integrated pest management (IPM) practices. Not only can IPM result in more profitable agriculture due to the reduction of pest control costs but also assures equitable, secure, sufficient, and stable flows of both food and ecosystem services. Despite those ecological and economic benefits, the vast areas of cultivated soybean as well as the convenience of spraying insecticides are encouraging the adoption of prophylactic pest control as a relatively inexpensive safeguard compared to IPM practices. Thus, in this forum, we discuss the reasons for soybean IPM not reaching its potential. We give examples of how we can revive this once successful pest management program with a focus on experiences in Brazil and the USA. We analyze IPM case studies to illustrate the need for growers to have easy and fast access to IPM information on its medium- and long-term benefits. Overall, this forum highlights the importance of IPM for agricultural sustainability including ecological and financial benefits.

The Fitness and Economic Benefits of Rearing the Parasitoid Telenomus podisi Under Fluctuating Temperature Regime.

Successful biological control requires detailed knowledge about the mass rearing conditions of the control agents in order to ensure higher quality of field-released insects. Thus, we investigated whether rearing fluctuating thermal condition would affect the fitness and costs of the parasitoid wasp Telenomus podisi Ashmead (a biocontrol agent used for controlling the Neotropical brown stink bug Euschistus heros (Fabricius)) when compared with parasitoid reared at constant temperature condition, which is commonly used in insect facilities. Parasitoids were reared under either constant (continuous exposure at 25 ± 2°C) or fluctuating temperature conditions (i.e., 30 ± 2°C during day and 20 ± 2°C at night) during four consecutive generations. Our results indicated that tested fluctuating temperature is more suitable for rearing of T. podisi as such temperature condition not only resulted in fitness benefits (e.g., shorter developmental time, longer female longevity, higher fecundity/fertility) but also reduced (approximately 23.5%) the estimated costs for producing the parasitoids. Furthermore, rearing T. podisi under fluctuating temperatures improved tolerance to low constant temperatures (i.e., 20°C) without changing the tolerance to constant high temperatures (30°C) in the fourth generation. Surprisingly, even parasitoids that developed under fluctuating thermal conditions performed better than those reared at constant temperature of 25°C. Collectively, our findings suggest that T. podisi reared under fluctuating thermal condition can tolerate better fluctuating temperatures that normally occur both during long periods of transport and in agricultural ecosystems, which will increase the quality and productivity of mass-reared T. podisi for inundative releases.

Effect of the Ages of Parasitoid and Host Eggs on Telenomus podisi (Hymenoptera: Platygastridae) Parasitism.

This study investigates the influence of parasitoid age and egg age of the hosts Euschistus heros (Fabricius) and Dichelops melacanthus (Dallas) on parasitism of Telenomus podisi Ashmead. Six separate bioassays were conducted: parasitism on eggs of E. heros (bioassay 1) and D. melacanthus (bioassay 2) by T. podisi females of different age (1, 5, and 10 days old); parasitism by T. podisi on eggs of different age (1, 2, 3, 4, and 5 days of embryonic development) of the hosts E. heros (bioassay 3) and D. melacanthus (bioassay 4); preference of T. podisi females for eggs at different embryonic developmental stages (eggs of 1, 2, 3, 4, and 5 days) of the hosts E. heros (bioassay 5) and D. melacanthus (bioassay 6). The age of T. podisi females and their hosts affected parasitism on both E. heros and D. melacanthus eggs. Overall, the parasitism rate was higher in older than younger parasitoids, independent of the tested host species, and host eggs between 1 and 3 days old were similarly parasitized. Thus, in T. podisi mass rearing facilities, it is recommended to use older adults (5 to 10 days old) as mother wasps to increase parasitism on the offered eggs. In addition, when hosts are completely absent in the field, or climatic conditions are unfavorable for release, mass-reared adults can be kept in the laboratory (25°C) for up to 10 days for later release in the field without any impairment of their subsequent parasitism performance.

Use of Low Temperature Storage to Preserve Host and Parasitoid to Improve the Rearing of Telenomus podisi (Hymenoptera: Platygastridae) on Euschistus heros (Hemiptera: Pentatomidae) Eggs.

Successful parasitoid rearing is crucial for augmentative biological control. A low temperature preservation protocol allowing the availability of host and parasitoid year-round was evaluated in this study in four bioassays: (1) host eggs [Euschistus heros (Fabricius)] stored at - 196, - 80, and - 20°C for up to 70 days prior to exposure to Telenomus podisi Ashmead parasitism; (2) Euschistus heros eggs removed from storage at - 196°C after 70 days and kept at 5°C for up to 9 days prior to exposure to T. podisi parasitism; (3) Telenomus podisi adult emergence of insects stored as pupae at 5°C; and (4) fitness of adults of T. podisi stored at 5°C. Higher parasitism was observed in parasitoids reared on E. heros eggs stored at - 196 and - 80°C. Host eggs removed from - 196°C and stored at 5°C for up to 6 days did not impact T. podisi parasitism and development. Storage of T. podisi pupae for more than 7 days negatively affected parasitoid biology. Storing T. podisi adults at 5°C for up to 6 days does not alter the biological parameters of the parasitoid. Thus, parasitoids can be stored as pupae or adults as well as its host E. heros eggs. Our findings can be applied to improve the feasibility of year-round insect production.

Host Preferences of Telenomus podisi (Hymenoptera: Scelionidae): Parasitism on Eggs of Dichelops melacanthus, Euschistus heros, and Podisus nigrispinus (Hemiptera: Pentatomidae).

Successful biological control requires detailed knowledge about host preferences of the released parasitoid, because the presence of alternative hosts may affect the control of the target pest. The objective of this work was therefore to evaluate host preferences of Telenomus podisi Ashmead among the eggs of three stink bug species: Dichelops melacanthus Dallas, Euschistus heros Fabricius, and Podisus nigrispinus Dallas (Heteroptera: Pentatomidae). Three independent experiments were carried out to study host preferences among the following: (1) E. heros, D. melacanthus dallas, and P. nigrispinus (bioassay 1); (2) E. heros and D. melacanthus (bioassay 2); and (3) D. melacanthus and P. nigrispinus (bioassay 3). A single bioassay (bioassay 4) was carried out to evaluate the egg size of E. heros, D. melacanthus, and P. nigrispinus. Two more bioassays were carried out: bioassay 5 to study the biological characteristics of T. podisi reared on E. heros, D. melacanthus, and P. nigrispinus eggs, and bioassay 6 to study the morphological characters of T. podisi reared on those different host eggs. Overall, T. podisi consistently preferred eggs of D. melacanthus to those of the other studied hosts, due to probably their better nutritional value; hypothesis that is supported by the fast T. podisi development and bigger parasitoids when reared on D. melacanthus and P. nigrispinus eggs. This allows suggesting that neither pre-imaginal conditioning nor associative learning nor α-conditioning are relevant to T. podisi parasitism. Thus, E. heros eggs could be successfully used for mass rearing of this parasitoid for successive generations since it would not affect its parasitism on other species of the Pentatomidae family in the field.

Impact of Insecticides Used in Soybean Crops to the Egg Parasitoid Telenomus podisi (Hymenoptera: Platygastridae).

The objective of this study was to evaluate possible side effects of insecticides used in soybean crops on pupae and adults of the egg parasitoid Telenomus podisi Ashmead (Hymenoptera: Platygastridae) under laboratory conditions. The protocol was adapted from standard methodology stablished by the Pesticides and Beneficial Organisms Working Group of the International Organization for Biological and integrated Control (IOBC) for Trichogramma cacoeciae (Marchal) (Hymenoptera: Trichogrammatidae). All tested benzoylureas, diacylhydrazines, diamides and spinosins as well as pyrethroid beta-cyfluthrin were harmless to T. podisi pupae and adults, and therefore, can be used in IPM without damage to this biological control agent. The tested organophosphate, pyrethroids (except beta-cyfluthrin) and its combinations with either neonicotinoids or diamides triggered deleterious effects on at least one of the life stages of the parasitoid and should, whenever possible, be replaced by other insecticides more selective to natural enemies.

Low Temperature Storage of Telenomus remus (Nixon) (Hymenoptera: Platygastridae) and its Factitious Host Corcyra cephalonica (Stainton) (Lepidoptera: Pyralidae).

We conducted three bioassays to evaluate the effect of low-temperature storage of eggs (host) and pupae and adults (parasitoid) on the biology and parasitism capacity of the egg parasitoid Telenomus remus (Nixon) (Hymenoptera: Platygastridae). Viable stored Corcyra cephalonica (Stainton) (Lepidoptera: Pyralidae) eggs were parasitized to the same degree or even higher than fresh eggs when stored until 14 days at 5°C or until 21 days at 10°C. In contrast, the percentage of parasitized sterilized eggs was equal to the control only when stored for 7 and 14 days. Survival of T. remus pupae declined with storage time at both studied temperatures (5 and 10°C). However, after 7 days of storage, survival of pupae was still 86.3 and 64.9% at 10 and 5°C, respectively. The number of adult male survivors remained similar until the fourth storage day at both 5 and 10°C. In contrast, female survival did not differ until day 8 at 10°C or day 6 at 5°C. Parasitism capacity of stored adults was not altered by storage compared with the control. Therefore, we conclude that the maximal storage time at 10°C is 21 days for viable C. cephalonica eggs and 7 days for T. remus pupae, while parasitoid adults should not be stored for more than 4 days at either 5 or 10°C.

Side-Effects of Glyphosate to the Parasitoid Telenomus remus Nixon (Hymenoptera: Platygastridae).

The aim of this study was to compare the side-effects of glyphosate to the parasitoid Telenomus remus Nixon (Hymenoptera: Platygastridae) when parasitoids were exposed to this chemical at the pupal (inside host eggs) and adult stages. Bioassays were conducted under laboratory conditions according to the International Organization for Biological Control (IOBC) standard methods for testing side-effects of pesticides to egg parasitoids. Different glyphosate-based pesticides (Roundup Original®, Roundup Ready®, Roundup Transorb®, Roundup WG®, and Zapp Qi®) were tested at the same acid equivalent concentration. Treatments were classified following the IOBC toxicity categories as (1) harmless, (2) slightly harmful, (3) moderately harmful, and (4) harmful. When tested against T. remus adults, Roundup Original®, Roundup Ready®, Roundup Transorb®, and Roundup WG® reduced parasitism 2 days after parasitoid emergence, being classified as slightly harmful. Differently, when tested against T. remus pupae, all tested glyphosate-based products did not differ in their lethal effect and therefore did not reduce T. remus adult emergence or parasitism capacity, being classified as harmless. However, differences on sublethal toxicity were found. Parasitism of individuals emerging from parasitized eggs sprayed at the pupal stage of T. remus with Zapp Qi® was lower compared to control, but parasitism was still higher than 66%, and therefore, Zapp Qi® was still classified as harmless. In conclusion, all tested glyphosate-based products can be used in agriculture without negative impact to T. remus as none was classified as harmful or moderately harmful to this parasitoid when exposure occurred at the pupal or adult stages.

Selectivity of Organic Products to Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae).

The selectivity of various entomopathogens and one insecticide (chlorpyrifos = positive control) to Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) was evaluated in the laboratory, using the protocol established by the Working Group on "Pesticides and Beneficial Organisms" of the IOBC. The evaluated parameters were parasitism (%), adult emergence (%), and product repellency to the parasitoid when sprayed on host eggs prior to parasitism (free-choice and no-choice tests). Most of the studied entomopathogens (Bacillus thuringiensis var. kurstaki, Bacillus thuringiensis var. aizawai, Beauveria bassiana, Metarhizium anisopliae, and Trichoderma harzianum) had no effects on biological parameters and were classified as harmless to T. pretiosum. Emergence of parasitoids (progeny viability) was reduced, but remained above 90%, when host eggs were sprayed with Baculovirus anticarsia prior to parasitism in the free-choice test, and B. anticarsia was therefore considered harmless. Chlorpyrifos (positive control) caused high adult parasitoid mortality in all bioassays. While T. pretiosum and the tested entomopathogens may be used simultaneously in integrated pest management programs, the use of chlorpyrifos should be avoided.

Telenomus remus Nixon egg parasitization of three species of Spodoptera under different temperatures.

Telenomus remus Nixon is a promising biocontrol agent as an egg parasitoid of Spodoptera spp., but the lack of information on the host-parasitoid interactions in this system precludes its applied use in agriculture. Therefore, we studied the parasitism capacity of T. remus on eggs of Spodoptera cosmioides (Walker), Spodoptera eridania (Cramer), and Spodoptera frugiperda (Smith) in a range of temperatures (19, 22, 25, 28, 31, and 34 ± 1°C) under controlled conditions (70 ± 10% RH and 12 h photophase). Egg masses of Spodoptera spp. were offered to a single-mated T. remus female on a daily basis. More than 80% lifetime parasitism on eggs of S. cosmioides, S. frugiperda, and S. eridania was reached from 1 to 5, 1 to 7, and 1 to 9 days, respectively, at temperatures from 19 to 34°C. More than 80% parasitization was obtained at extreme temperatures for all hosts studied. Lifetime parasitization of S. frugiperda, S. cosmioides, and S. eridania was affected by temperature, with the lowest values for S. frugiperda (34°C) and S. cosmioides (19 and 34°C). Parasitization of S. eridania eggs was reduced around 18% at 28 and 31°C, but dropped more severely at 34°C. Parasitoid longevity was reduced as temperature increased. Thus, our data indicated that T. remus might be suitable as a biocontrol agent against S. eridania, S. cosmioides, and S. frugiperda in geographical areas that fit the temperature range studied here, even though T. remus parasitism was reduced at 34°C.

Economic Thresholds in Soybean-Integrated Pest Management: Old Concepts, Current Adoption, and Adequacy.

Increasing global demands for food underline the need for higher crop yields. The relatively low costs of the most commonly used insecticides in combination with increasing soybean market prices led growers and technical advisors to debate the adequacy of recommended economic thresholds (ETs). The adoption of ETs and pest sampling has diminished in Brazil, leading to excessive pesticide use on soybean. The reduced efficacy of natural biological control, faster pest resurgence, and environment contamination are among the side-effects of pesticide abuse. To address these problems and maximize agricultural production, pest control programs must be guided by a proper integrated pest management (IPM) approach, including the ET concept. Therefore, the most appropriate time to initiate insecticide spraying in soybean is indicated by the available ETs which are supported by experiments over the last 40 years in different edapho-climatic conditions and regions with distinct soybean cultivars. Published scientific data indicate that preventive insecticide use is an expensive and harmful use of chemicals that increases the negative impact of pesticides in agroecosystems. However, the established ETs are for a limited number of species (key pests), and they only address the use of chemicals. There is a lack of information regarding secondary pests and other control strategies in addition to insecticides. It is clear then that much progress is still needed to improve ETs for pest management decisions. Nevertheless, using the current ETs provides a basis for reducing the use of chemicals in agriculture without reducing yields and overall production, thereby improving sustainability.

Resistance of soybean genotypes to Bemisia tabaci (Genn.) Biotype B (Hemiptera: Aleyrodidae).

The silverleaf whitefly Bemisia tabaci (Genn.) biotype B has become a serious problem for soybean cultivation because it can significantly reduce soybean productivity. The use of soybean cultivars resistant to whitefly attack is an important strategy in an integrated pest management (IPM) program. This study evaluated the preference for oviposition and colonization by B. tabaci biotype B on different soybean genotypes. In the free-choice test, the genotypes studied were 'IAC 17' and 'IAC 19' as the standards for resistance and 'IAC Holambra Stwart' as the standard for susceptibility, as well as BABR01-0492, BABR01-0173, BABR01-1259, BABR01-1576, BABR99-4021HC, BABR99-4021HP, 'Barreiras', 'Conquista', 'Corisco', 'BRS Gralha', PI274454, PI227687, and PI171451. In the no-choice test, the four best genotypes selected in the free-choice test, in addition to the susceptible and resistant standards were evaluated. Our data indicated 'Barreiras' as the most resistant genotype against B. tabaci biotype B. 'BRS Gralha', which was the least attractive to whitefly adults in the free-choice test, did not show resistance to insect attack when they were confined in cages in the no-choice test. Despite the high number of eggs observed, BABR01-1576 and BABR99-4021HC showed a reduced number of nymphs, indicating antibiosis. The genotypes with a high level of resistance can be used as a tool against B. tabaci in IPM or as a source of resistance in plant-breeding programs.

Seletividade de produtos fitossanitários utilizados na cultura da soja para pupas de Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae) / Selectivity of pesticides used in soybean crops to Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae) pupae

O objetivo do trabalho foi avaliar o efeito de produtos fitossanitários sobre pupas de Trichogramma pretiosum. Foram conduzidos três bioensaios em delineamento inteiramente casualizado com 11 tratamentos e cinco repetições. Em cada repetição, ovos de Anagasta kuehniella (Zeller, 1879) (Lepidoptera: Pyralidae) foram utilizados como hospedeiro alternativo, sendo aderidos em cartelas de cartolina de 1 cm2 com solução de goma arábica à 40% e oferecidos para o parasitismo por 24h. Após 168-192h do parasitismo, quando os parasitoides estavam na fase de pupa, as cartelas foram mergulhadas por cinco segundos nos tratamentos testados. Avaliou-se a sobrevivência dos indivíduos tratados e a redução na emergência dos parasitoides foi classificada segundo as normas da IOBC. Os inseticidas flufenoxurom (Cascade®) 10, diflubenzurom (Dimilin®) 20 e metoxifenozide (Intrepid 240SC®) 21,6 e 36 g i.a. ha-1 foram classificados como inócuos. Permetrina (Valon 384 CE®) 49,92; betaciflutrina 12,5 + imidacloprido 100 (Connect®) e gama-cialotrina (Stallion 150SC®) 3,75 g i.a. ha-1 foram levemente nocivos. Clorpirifós (Lorban 480BR®) 384 e espinosade (Tracer®) 24 g i.a. ha-1 foram moderadamente nocivos. Os herbicidas glifosato 720 + imazetapir 90 (Alteza®); s-metolacloro (Dual Gold®) 1920; flumioxazina (Flumyzin 500®) 60; clomazona (Gamit®) 1000; glifosato 2880 (Gliz 480SL®); dicloreto de paraquate 600 + diurom 300 (Gramocil®); glifosato 1200 (Roundup Ready®); foram classificados como inócuos e os herbicidas 2,4-D (DMA 806BR®) 1209; dicloreto de paraquate (Gramoxone®) 600; glifosato (Roundup Transorb®) 2592 g i.a. ha-1 classificados como levemente nocivos. Os fungicidas tiofanato-metílico (Cercobin 500 SC®) 400; flutriafol 60 + tiofanato-metílico 300 (Celeiro®); carbendazin (Derosal 500SC®) 250; tebuconazole (Folicur EC®) 150; flutriafol (Impact®) 125; tebuconazole 120 + trifloxistrobina 60 (Nativo®); epoxiconazole 30 + piraclostrobina 79,8 (Opera®); epoxiconazole (Opus SC®) 12,5; azoxistrobina (Priori®) 50; azoxistrobina 60 + ciproconazole 24 (Priori Xtra®) g i.a. ha-1 foram classificados como inócuos aT. pretiosumna fase de desenvolvimento avaliada (pupa). Dentre os produtos avaliados, aqueles classificados como inócuos devem ser priorizados no manejo integrado de pragas (MIP) por compatibilizar o uso do controle químico sem prejudicar o controle biológico. Do mesmo modo, os produtos classificados como moderadamente nocivos devem ser evitados sempre que possível ou substituídos por outro de menor impacto.

This study aimed to evaluate the effect of different pesticides onTrichogramma pretiosumpupae. Three tests were carried out with 11 treatments and 5 replications. Eggs ofAnagasta kuehniella (Zeller, 1879) (Lepidoptera: Pyralidae) were used as a factitious host affixed on 1cm2 pieces of cardboard using a non-noxious glue solution (40% gum arabic) and then offered to parasitism for 24 h. After 168­192 h from the parasitism, when the parasitoids were at the pupae stage, the pieces of cardboard were dipped for five seconds in the treatments. The parasitoid survival was evaluated and the emergence was classified accordingly to the IOBC guidelines. The insecticides flufenoxuron (Cascade®) 10, diflubenzuron (Dimilin®) 20 and methoxyfenozide (Intrepid 240SC®) 21.6 and 36 g a.i. ha-1 were classified as harmless. Permethrin (Valon 384CE®) 49.92, beta-cyfluthrin 12.5 + imidacloprid 100 (Connect®) and gammacyhalothrin (Stallion 150SC®) 3.75 g a.i. ha-1 were slightly harmful. Chlorpyriphos (Lorsban 480BR®) 384 and spinosad (Tracer®) 24 g a.i. ha-1 were moderately harmful. The herbicides glyphosate 720 + imazetapyr 90 (Alteza®), s-metolachlor (Dual Gold®) 1920, flumyoxazin (Flumyzin 500®) 60, clomazone (Gamite®) 1000, glyphosate (Gliz®) 2880, paraquat dichloride 600 + diuron 300 (Gramocil®), glyphosate 1200 (Roundup Ready®) were classified as harmless, and the herbicides 2.4-D (DMA®) 1209, paraquat dichloride (Gramoxone®) 600 and glyphosate (Roundup Transorb®) 2592 g a.i. ha-1 were classified as slightly harmful. The fungicides metil tiofanate (Cercobin 500SC®) 400, flutriafol 60 + metil tiofanate 300 (Celeiro®), carbendazin (Derosal 500SC®) 250, tebuconazol (Folicur EC®) 150, flutriafol (Impact®) 125, tebuconazol 120 + trifloxystrobin 60 (Nativo®), epoxiconazol 30 + piraclostrobin 79.8 (Opera®), epoxiconazol (Opus SC®) 12.5, azoxystrobin (Priori®) 50, azoxystrobin 60 + ciproconazol 24 (Priori Xtra®) g a.i. ha-1 were harmless toT. pretiosum pupae. Among the tested products, the harmless ones should be chosen in a program of integrated pest management (IPM) since it allows the use of pesticides without harm to the biological control. On the other hand, the moderately harmful pesticides should be avoided or replaced by another product with less impact whenever it is possible.

Efeito do tratamento de sementes com inseticidas no controle de pragas iniciais e na qualidade fisiológica das sementes em girassol / The effect of various insecticides on the control of initial pests and on the physiological quality of sunflower seeds

Avaliou-se o uso de inseticidas em tratamento de sementes de girassol no controle das pragas Cerotoma arcuatus (Olivier) (Coleoptera: Chrysomelidae), Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae) e Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) e a influência desses inseticidas na qualidade fisiológica das sementes, durante o armazenamento. Os resultados obtidos mostraram que tiodicarbe 600 g i.a./ 100 kg de sementes proporcionou aproximadamente 80, 100 e 85% de controle de A. gemmatalis de 1º ínstar, S. frugiperda de 2º ínstar e adultos de C. arcuatus, respectivamente. Entretanto, esse mesmo tratamento foi ineficiente no controle de lagartas de S. frugiperda de 3º ínstar e de B. tabaci. No controle de adultos de C. arcuatus, além de tiodicarbe 600 g i.a./100 kg sementes que apresentou bons resultados, tiodicarbe + imidacloprido 157,5 + 52,5 g i.a., tiametoxam 210 e 280 g i.a., imidacloprido 245 e fipronil 50 g i.a./100 kg de sementes apresentaram eficiência acima de 80% no controle dessa praga. No controle da A. gemmatalis apenas fipronil 50 g i.a./100 kg sementes e azadiractina 10 e 20 g. i.a./100 kg de sementes proporcionaram valores menores que 80% de controle, nas doses testadas, enquanto que, para o manejo da mosca-branca, nenhum dos tratamentos estudados proporcionou controle superior a 80%. Nenhum dos inseticidas avaliados nos diferentes tempos de armazenamento (até quatro meses após o tratamento) prejudicou a germinação e a emergência das sementes.

The aim of this study was to test various insecticides in the treatment of sunflower seeds for the control of Cerotoma arcuatus (Olivier) (Coleoptera: Chrysomelidae), Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae) and Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), and assessing their influence on the physiological quality of seeds during storage. The results showed that tiodicarb 600 g.a.i./100 kg of seeds achieved close to 80, 100 and 85% of control against first-instar A. gemmatalis, second instar S. frugiperda and adult C. arcuatus, respectively. However, this treatment was inefficient against third instar S. frugiperda and B. tabaci. Tiodicarb + imidacloprid 157.5 + 52.5; thiamethoxan 210; thiamethoxan 280; imidacloprid 245 and fipronil 50 g.a.i./100 kg of seeds also achieved 80% control against C. arcuatus adults. Against A. gemmatalis, only fipronil 50 g.a.i. and azarachtin 10 and 20 g.a.i./100 kg of seeds did not achieve more than 80% control. Against B. tabaci no tested treatment reached 80% of efficacy. None of the tested insecticides harmed seed germination or emergence during the different storage periods (up to 4 months after seed treatment).

SELETIVIDADE DE PRODUTOS FITOSSANITÁRIOS UTILIZADOS NA CULTURA DA SOJA PARA PUPAS DE TRICHOGRAMMA PRETIOSUM RILEY, 1879 (HYMENOPTERA: TRICHOGRAMMATIDAE)

ABSTRACT SELECTIVITY OF PESTICIDES USED IN SOYBEAN CROPS TOTRICHOGRAMMA PRETIOSUM RILEY, 1879 (HYMENOPTERA: TRICHOGRAMMATIDAE) PUPAE. This study aimed to evaluate the effect of different pesticides onTrichogramma pretiosumpupae. Three tests were carried out with 11 treatments and 5 replications. Eggs ofAnagasta kuehniella (Zeller, 1879) (Lepidoptera: Pyralidae) were used as a factitious host affixed on 1cm2 pieces of cardboard using a non-noxious glue solution (40% gum arabic) and then offered to parasitism for 24 h. After 168192 h from the parasitism, when the parasitoids were at the pupae stage, the pieces of cardboard were dipped for five seconds in the treatments. The parasitoid survival was evaluated and the emergence was classified accordingly to the IOBC guidelines. The insecticides flufenoxuron (Cascade®) 10, diflubenzuron (Dimilin®) 20 and methoxyfenozide (Intrepid 240SC®) 21.6 and 36 g a.i. ha-1 were classified as harmless. Permethrin (Valon 384CE®) 49.92, beta-cyfluthrin 12.5 + imidacloprid 100 (Connect®) and gammacyhalothrin (Stallion 150SC®) 3.75 g a.i. ha-1 were slightly harmful. Chlorpyriphos (Lorsban 480BR®) 384 and spinosad (Tracer®) 24 g a.i. ha-1 were moderately harmful. The herbicides glyphosate 720 + imazetapyr 90 (Alteza®), s-metolachlor (Dual Gold®) 1920, flumyoxazin (Flumyzin 500®) 60, clomazone (Gamite®) 1000, glyphosate (Gliz®) 2880, paraquat dichloride 600 + diuron 300 (Gramocil®), glyphosate 1200 (Roundup Ready®) were classified as harmless, and the herbicides 2.4-D (DMA®) 1209, paraquat dichloride (Gramoxone®) 600 and glyphosate (Roundup Transorb®) 2592 g a.i. ha-1 were classified as slightly harmful. The fungicides metil tiofanate (Cercobin 500SC®) 400, flutriafol 60 + metil tiofanate 300 (Celeiro®), carbendazin (Derosal 500SC®) 250, tebuconazol (Folicur EC®) 150, flutriafol (Impact®) 125, tebuconazol 120 + trifloxystrobin 60 (Nativo®), epoxiconazol 30 + piraclostrobin 79.8 (Opera®), epoxiconazol (Opus SC®) 12.5, azoxystrobin (Priori®) 50, azoxystrobin 60 + ciproconazol 24 (Priori Xtra®) g a.i. ha-1 were harmless toT. pretiosum pupae. Among the tested products, the harmless ones should be chosen in a program of integrated pest management (IPM) since it allows the use of pesticides without harm to the biological control. On the other hand, the moderately harmful pesticides should be avoided or replaced by another product with less impact whenever it is possible.

RESUMO O objetivo do trabalho foi avaliar o efeito de produtos fitossanitários sobre pupas de Trichogramma pretiosum. Foram conduzidos três bioensaios em delineamento inteiramente casualizado com 11 tratamentos e cinco repetições. Em cada repetição, ovos de Anagasta kuehniella (Zeller, 1879) (Lepidoptera: Pyralidae) foram utilizados como hospedeiro alternativo, sendo aderidos em cartelas de cartolina de 1 cm2 com solução de goma arábica à 40% e oferecidos para o parasitismo por 24h. Após 168-192h do parasitismo, quando os parasitoides estavam na fase de pupa, as cartelas foram mergulhadas por cinco segundos nos tratamentos testados. Avaliou-se a sobrevivência dos indivíduos tratados e a redução na emergência dos parasitoides foi classificada segundo as normas da IOBC. Os inseticidas flufenoxurom (Cascade®) 10, diflubenzurom (Dimilin®) 20 e metoxifenozide (Intrepid 240SC®) 21,6 e 36 g i.a. ha-1 foram classificados como inócuos. Permetrina (Valon 384 CE®) 49,92; betaciflutrina 12,5 + imidacloprido 100 (Connect®) e gama-cialotrina (Stallion 150SC®) 3,75 g i.a. ha-1 foram levemente nocivos. Clorpirifós (Lorban 480BR®) 384 e espinosade (Tracer®) 24 g i.a. ha-1 foram moderadamente nocivos. Os herbicidas glifosato 720 + imazetapir 90 (Alteza®); s-metolacloro (Dual Gold®) 1920; flumioxazina (Flumyzin 500®) 60; clomazona (Gamit®) 1000; glifosato 2880 (Gliz 480SL®); dicloreto de paraquate 600 + diurom 300 (Gramocil®); glifosato 1200 (Roundup Ready®); foram classificados como inócuos e os herbicidas 2,4-D (DMA 806BR®) 1209; dicloreto de paraquate (Gramoxone®) 600; glifosato (Roundup Transorb®) 2592 g i.a. ha-1 classificados como levemente nocivos. Os fungicidas tiofanato-metílico (Cercobin 500 SC®) 400; flutriafol 60 + tiofanato-metílico 300 (Celeiro®); carbendazin (Derosal 500SC®) 250; tebuconazole (Folicur EC®) 150; flutriafol (Impact®) 125; tebuconazole 120 + trifloxistrobina 60 (Nativo®); epoxiconazole 30 + piraclostrobina 79,8 (Opera®); epoxiconazole (Opus SC®) 12,5; azoxistrobina (Priori®) 50; azoxistrobina 60 + ciproconazole 24 (Priori Xtra®) g i.a. ha-1 foram classificados como inócuos aT. pretiosumna fase de desenvolvimento avaliada (pupa). Dentre os produtos avaliados, aqueles classificados como inócuos devem ser priorizados no manejo integrado de pragas (MIP) por compatibilizar o uso do controle químico sem prejudicar o controle biológico. Do mesmo modo, os produtos classificados como moderadamente nocivos devem ser evitados sempre que possível ou substituídos por outro de menor impacto.

EFEITO DO TRATAMENTO DE SEMENTES COM INSETICIDAS NO CONTROLE DE PRAGAS INICIAIS E NA QUALIDADE FISIOLÓGICA DAS SEMENTES EM GIRASSOL

ABSTRACT The aim of this study was to test various insecticides in the treatment of sunflower seeds for the control of Cerotoma arcuatus (Olivier) (Coleoptera: Chrysomelidae), Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae) and Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), and assessing their influence on the physiological quality of seeds during storage. The results showed that tiodicarb 600 g.a.i./100 kg of seeds achieved close to 80, 100 and 85% of control against first-instar A. gemmatalis, second instar S. frugiperda and adult C. arcuatus, respectively. However, this treatment was inefficient against third instar S. frugiperda and B. tabaci. Tiodicarb + imidacloprid 157.5 + 52.5; thiamethoxan 210; thiamethoxan 280; imidacloprid 245 and fipronil 50 g.a.i./100 kg of seeds also achieved 80% control against C. arcuatus adults. Against A. gemmatalis, only fipronil 50 g.a.i. and azarachtin 10 and 20 g.a.i./100 kg of seeds did not achieve more than 80% control. Against B. tabaci no tested treatment reached 80% of efficacy. None of the tested insecticides harmed seed germination or emergence during the different storage periods (up to 4 months after seed treatment).

RESUMO Avaliou-se o uso de inseticidas em tratamento de sementes de girassol no controle das pragas Cerotoma arcuatus (Olivier) (Coleoptera: Chrysomelidae), Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae) e Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) e a influência desses inseticidas na qualidade fisiológica das sementes, durante o armazenamento. Os resultados obtidos mostraram que tiodicarbe 600 g i.a./ 100 kg de sementes proporcionou aproximadamente 80, 100 e 85% de controle de A. gemmatalis de 1º ínstar, S. frugiperda de 2º ínstar e adultos de C. arcuatus, respectivamente. Entretanto, esse mesmo tratamento foi ineficiente no controle de lagartas de S. frugiperda de 3º ínstar e de B. tabaci. No controle de adultos de C. arcuatus, além de tiodicarbe 600 g i.a./100 kg sementes que apresentou bons resultados, tiodicarbe + imidacloprido 157,5 + 52,5 g i.a., tiametoxam 210 e 280 g i.a., imidacloprido 245 e fipronil 50 g i.a./100 kg de sementes apresentaram eficiência acima de 80% no controle dessa praga. No controle da A. gemmatalis apenas fipronil 50 g i.a./100 kg sementes e azadiractina 10 e 20 g. i.a./100 kg de sementes proporcionaram valores menores que 80% de controle, nas doses testadas, enquanto que, para o manejo da mosca-branca, nenhum dos tratamentos estudados proporcionou controle superior a 80%. Nenhum dos inseticidas avaliados nos diferentes tempos de armazenamento (até quatro meses após o tratamento) prejudicou a germinação e a emergência das sementes.