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Being capable of infesting a wide variety of plant species, the whitefly Bemisia tabaci MEAM1 (Hemiptera: Aleyrodidae) is responsible for severe losses in numerous agricultural crops. In order to increase knowledge regarding interactions involving B. tabaci MEAM1 and plants associated with agricultural landscapes, the present study sought to identify preferential hosts by comparing 15 different common weed species and five cultivated plants (tomato, bell pepper, soybean, maize and cotton) through free and no-choice tests. Additionally, a possible correlation between physical-morphological plant aspects and insect’s colonization behavior was assessed. Positive correlations were verified between the oviposition index and trichome density, and between the number of adults and b* (yellow intensity) index. Negative correlations were observed between the number of adults and L* and a* (luminosity and green intensity, respectively) indexes. In the free choice test, the species Solanum lycopersicum, Senna obtusifolia, Glycine max, Emilia sonchifolia and Euphorbia heterophylla were the most infested during the mean of the evaluation periods, differing from Spermacoce latifolia, Amaranthus viridis and Richardia brasiliensis, which presented the lowest means of insect infestation. In this same test, S. lycopersicum and E. sonchifolia had the greatest oviposition, differing from most of the species. In the no-choice test, E. heterophylla, Galinsoga parviflora and S. latifolia had the highest means of eggs and nymphs per cm². Our results show evidence of the expressive potential of weed species frequently found in Brazilian agricultural fields, such as E. sonchifolia, S. obtusifolia, and E. heterophylla, as alternative hosts of B. tabaci MEAM1.

Made available in DSpace on 2021-06-25T12:16:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-05-21 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Changes in Brazilian corn production practices, have favored stink bugs, which feed on corn seedlings. Diceraeus melacanthus (Dallas) (Hemiptera: Pentatomidae), is a key pest in corn, and Euschistus heros (F.) (Hemiptera: Pentatomidae) is an emerging threat to corn. Economic thresholds (ET) for management of stink bugs are usually calculated based on the injury caused by adults. However, little is known about the impact of stink bug nymphs on corn seedlings. Thus, this work evaluated the effects of infestation with different nymphal instars on corn seedling weight (fresh and dry), plant height and stalk diameter. We also classified the level of overall injury to the seedlings using a rating scale. Corn seedlings in the V3 stage were infested with two insects of either D. melacanthus or E. heros in the 2(nd), 3(rd), 4(th), 5(th) instars or adult stage in separate greenhouse studies performed for each species. Plants without infestation were used as controls. Both species of stink bugs feeding on corn seedlings affected all the assessed parameters. The quantitative measures of seedling size (i.e., fresh weight, dry weight, plant height and stem diameter) were generally most severely affected by the 5(th) instars and adults of D. melacanthus and the 4(th) instars of E. heros. The qualitative injury rating scale generally showed a greater impact to seedlings by 3(rd) instar to adult life stages of each species. Across life stages, injury to seedlings caused by D. melacanthus was numerically greater than that from E. heros. These results will guide the development of a more accurate ETs for stink bug management on seedling corn plants. Sao Paulo State Univ, Sch Agr, Dept Crop Protect, BR-18610034 Botucatu, SP, Brazil Fed Univ Grande Dourados, Dept Entomol & Biodivers Conservat, BR-79804970 Dourados, MS, Brazil Agr Res & Rural Extens Co Santa Catarina, BR-89801970 Chapeco, SC, Brazil Univ Minnesota, Dept Entomol, St Paul, MN 55108 USA Sao Paulo State Univ, Sch Agr, Dept Crop Protect, BR-18610034 Botucatu, SP, Brazil CAPES: 001 CNPq: 303892/2016-1

Made available in DSpace on 2021-06-25T11:56:53Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-04-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Halyomorpha halys (Stal) (Hemiptera: Pentatomidae) is an invasive species in the United States representing a great threat to crops of economic importance, such as soybean and corn. Due to the lack of information about its damage to early vegetative-stage corn, this study was conducted to provide information about H. halys damage to sweet corn seedlings. In the field experiment, caged sweet corn seedlings were exposed to sexed H. halys adults of densities of 0, 1, or 2 insects per plant for 7 d. In a complementary greenhouse experiment, caged sweet corn seedlings were exposed to 0 or 2 nonsexed H. halys at different stages (second to fifth instars and adult) per plant for 14 d. In both experiments, we evaluated plant fresh and dry weights, plant height, stalk diameter and plant injury (using a rating scale, 0 to 5). In the field experiment, plant injury based on the rating scale was greater in plants exposed to insects compared with the control. In the greenhouse experiment, fresh and dry weights, height and diameter of seedlings were lower for those exposed to fourth instars. This stage also caused greater injury based on the rating scale. In general, our results indicate that H. halys can feed on sweet corn seedlings, and that fourth instars cause more injury. The rating scale adapted here can be used for early identification of H. halys occurrence and to assess its injury in the field. Univ Minnesota, Dept Entomol, 1980 Folwell Ave, St Paul, MN 55108 USA Sao Paulo State Univ, Sch Agr, Dept Crop Protect, BR-18610034 Botucatu, SP, Brazil Univ Fed Vicosa, Dept Entomol, BR-36570900 Vicosa, MG, Brazil Res & Rural Extens Co Santa Catarina, Res Ctr Family Agr, BR-89801970 Chapeco, SC, Brazil Sao Paulo State Univ, Sch Agr, Dept Crop Protect, BR-18610034 Botucatu, SP, Brazil CAPES: 001

Made available in DSpace on 2021-06-26T02:53:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-02-06 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Severe attacks of Brevicoryne brassicae (Hemiptera: Aphididae) on brassica crops may lead to a significant decrease in yield and can cause plant death. Host plant resistance is considered a valuable tool in integrated pest management and can assist in reducing the damage caused by aphids. This study evaluated the behavioral and biological parameters of B. brassicae in 37 Brassica oleracea (L.) var. acephala genotypes, and aimed to characterize the mechanisms of antixenosis and/or antibiosis. In antixenosis, plants were arranged in a circle inside an arena, releasing to the center one hundred adult aphids. The number of insects was evaluated at 1, 2, 3, 6, and 24 h after infestation. For antibiosis, 30 adults were confined inside each clip-cage on each genotype. The total number of nymphs; number of nymphs per adult per day; total nymphs until 10 d after the first nymph had been produced; duration of the pre-reproductive phase; duration of the reproductive phase; nymphal survival; adult longevity; nymph-adult period and nymphal mortality at 5, 7 and 10 d were evaluated. Several genotypes showed be less infested and more harmful to B. brassicae on collard greens. The genotypes 20T, 24X, 18R, 22V, 15O, 19S, 27VA, and 17Q were the least infested in the antixenosis 24 h free-choice test. 2B, 5E, 8H, 19S, 21U, 27VA, 30OP, PE, MGH, and TP genotypes prevented B. brassicae from completing nymphal period, indicating antibiosis and/or antixenosis expression. 4D, GAU, 20 T, 14 N, and MGI genotypes prevented the aphid from reaching the reproductive phase. These genotypes may be useful for breeding programs that focus on the resistance of collard greens to aphids. Sao Paulo State Univ, Sch Agr, Dept Crop Protect, BR-18610034 Botucatu, SP, Brazil Univ Sao Paulo, Luiz de Queiroz Coll Agr, Dept Entomol & Acarol, BR-13418900 Piracicaba, SP, Brazil Sao Paulo State Univ, Sch Agr, Dept Crop Protect, BR-18610034 Botucatu, SP, Brazil CAPES: 001

Made available in DSpace on 2021-06-25T11:58:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-02-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Aphis gossypii Glover (Hemiptera: Aphididae) is a polyphagous species frequently associated with the presence of sooty mold and viruses lethal to plants. The purpose of this work was to characterize possible resistance categories of cotton genotypes against A. gossypii. Initially, a preliminary test was carried out with 78 genotypes, 15 of which were selected for infestation ability assays and the determination of the cumulative aphid-day rates. Posteriorly, these genotypes were also evaluated through antixenosis and antibiosis assays. The genotypes FM 910, FM 966 LL, Moco, Gossypium hirsutum var. punctatum L. (Malvaceae), Variedade Reba = BTK-12, Deltapine, Hi-Bred, Acala 4-42, IAC PV010-1664, IAC 21, Reba B-50 PR and FMT 709 inhibited the aphid colonization. In the infestation ability assay, G. hirsutum punctatum, IAC PV010-1664 and Acala 4-42 were the least infested. In a multiple-choice assay, Deltapine Smooth Leaf and Variedade Reba = BTK-12 were significantly less infested, suggesting antixenosis. In the antibiosis assay, Gossypium arboreum L. (Malvaceae) 1 showed the lowest number of nymphs, number of nymphs per adult per day and, number of nymphs at 10 d after the birth of the first nymph in addition to reducing the reproductive period, nymphal survival, adult longevity and, developmental time. In the FM 910, the number of nymphs produced per day and, at 10 d after the birth of the first nymph decreased, which also indicated resistance. The results obtained here are unprecedented and can be explored in breeding programs to develop insect-resistant cotton cultivars. Sao Paulo State Univ, Sch Agr, Dept Crop Protect, BR-18610034 Botucatu, SP, Brazil Fed Univ Grandes Dourados, Dept Entomol & Biodivers Conservat, BR-79825070 Dourados, MS, Brazil Sao Paulo State Univ, Sch Agr, Dept Econ Sociol & Technol, BR-18610307 Botucatu, SP, Brazil Univ Sao Paulo, Coll Agr, Dept Entomol & Acarol, BR-13418900 Piracicaba, SP, Brazil Sao Paulo State Univ, Sch Agr, Dept Crop Protect, BR-18610034 Botucatu, SP, Brazil Sao Paulo State Univ, Sch Agr, Dept Econ Sociol & Technol, BR-18610307 Botucatu, SP, Brazil CNPq: 141953/2014-4 CNPq: 302831/2010-0 CNPq: 303892/2016-1 CAPES: 001

Made available in DSpace on 2021-06-25T11:08:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-03-01 Stink bugs are considered limiting pests to important crops worldwide. In Brazil, the green-belly stink bug, Dichelops melacanthus Dallas (Hemiptera: Pentatomidae), has become a key pest to the young phase of corn crop, being a problem especially when it succeeds soybean in the field. Injuries caused by this species vary from holes on new leaves to plant death in severe attacks. The main control technique used to this pest are seed treatment and insecticide spraying. Although both methods show some efficiency, factors as outbreaks in the resistance to insecticides and the different susceptibility existent among stink bugs population, leads to the search of other control strategies. Thus, less harmful tools to the environment and humans are highly desirable. In this sense, resistant plants appear as a valuable alternative for insect management, being compatible with other IPM methods. This study evaluated the resistance of 16 corn genotypes to D. melacanthus in order to characterize antixenosis and/or antibiosis expression. Antixenosis was accessed through preference multi-choice test with 5th instar nymphs. For antibiosis assessment, 60 2nd instar nymphs were confined on seedlings of 13 selected genotypes. Seedlings of IAC 8046, IAC 8390 and SCS 156 Colorado corn genotypes were less infested by D. melacanthus at 24 h after bugs were released indicating antixenosis expression. Genotypes IAC 8390 and JM 2M60 negatively affected some biological parameters of the green belly stink bug, indicating the occurrence of antibiosis. These genotypes can be useful to breeding programs focusing on corn resistance to stink bugs species. Department of Crop Protection São Paulo State University (UNESP) School of Agriculture Research Center for Family Agriculture Research and Rural Extension Company of Santa Catarina Department of Entomology and Biodiversity Conservation Federal University of Grande Dourados Department of Entomology and Acarology University of São Paulo Luiz de Queiroz College of Agriculture Department of Entomology University of Minnesota, 1980 Folwell Ave. Department of Crop Protection São Paulo State University (UNESP) School of Agriculture

Made available in DSpace on 2021-06-25T15:03:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-06-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Embrapa Helicoverpa armigera is a pest of several crops causing significant economic impact. We evaluated the insect development on different vegetative and reproductive structures of cotton, maize, and soybean compared to artificial diet. One hundred individuals were evaluated per structure (cotton leaves and bolls; maize leaves, grains, and silk; soybean leaves and pods) and artificial diet. Centesimal analyses were performed on quantifiable nutrient contents in diets. The viability of immatures (eggs, larvae, and pupae) ranged from 30% on maize leaf to 74% on cotton bolls, while on the artificial diet, it was 70%. Maize, cotton, and soybean leaves provided viability of 30, 37, and 42%, respectively, revealing these leaves tissues are less favorable to the development of H. armigera immatures compared to 'reproductive tissues'. Centesimal composition of diets compared 14 common components in all diets, which correlated significantly with larval and pupal stages and/or pupal weight. Of the 12 dietary components that significantly affected larval development time, half were negatively correlated, indicating a decrease in developmental time from their increments. In general, when insects were confined separately to substrates, the artificial diet was the most suitable for H. armigera development compared to the evaluated natural diets. However, in natural conditions, the variability of available hosts must be considered. In addition, it is acceptable for moths to select more suitable hosts for oviposition, while their larvae move to other more suitable tissues of the same plant or even migrate to other plants. Univ Estadual Paulista, Fac Ciencias Agronom, Dept Protecao Vegetal, BR-18610034 Botucatu, SP, Brazil Embrapa Cerrados, BR 020 Km 18, BR-73310970 Planaltina, Brazil Univ Brasilia, BR-73345010 Planaltina, Brazil Univ Florida, West Florida Res & Educ Ctr, 4253 Expt Rd, Jay, FL 32565 USA Univ Estadual Paulista, Fac Ciencias Agronom, Dept Protecao Vegetal, BR-18610034 Botucatu, SP, Brazil CNPq: 303892/2016-1 CNPq: 308947/2014-2 CNPq: 403376/2013-0 CNPq: 476691/2013-3 CNPq: 47304/2013-8 CNPq: 462.254.711-20 Embrapa: 02.13.14.006.00.00 Embrapa: 03.14.00.107.00.00

This study aimed to characterize the quantitative and qualitative damage caused by Deois flexuosa (Walker) (Hemiptera: Cercopidae) adults in Axonopus catharinensis cv. SCS 315 Catarina and Cynodon dactylon (Tifton 85 and Jiggs cultivars) under different infestation densities and, consequently, the expression of tolerance-type resistance. For this purpose, potted plants were infested with different insect densities (0, 5, 10, 20, and 40 adults m

Made available in DSpace on 2022-04-28T19:47:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-04-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Bemisia tabaci (Genn.) MEAM1 (Middle East-Asia Minor) (Hemiptera: Aleyrodidae) is an important pest of collards, Brassica oleracea var. acephala. This insect reaches high levels of infestation in the field, causing direct damage to plants, compromising productivity. Concerns related to chemical control have resulted in a search for alternative methods to manage populations of B. tabaci in the field. The use of resistant genotypes is a potentially and a valuable strategy to manage this insect, reducing its populations below the level at which it causes economic damage. This work evaluated period of incubation, duration of each instar, nymphal period, nymphal survival, development egg-adult, and adult longevity of B. tabaci MEAM1 on 13 collard genotypes under laboratory conditions after a previous screening involving 32 genotypes for oviposition non-preference. The following parameters were determined: duration period per instar, total nymphal period, nymphal survival, total development period (egg-adult) and adult longevity. The genotypes P1C, MG and LG expressed antibiosis and/or antixenosis against B. tabaci MEAM1, prolonging the total development period (egg-adult) of the insect. IMAN W, MOP and VE reduced the nymphal survival of the whiteflies, indicating some potential for resistance. Due to the importance of collards cultivation and the substantial damage potential that this insect presents to the crop, the selection of resistant genotypes is promising and may represent a useful tool for the management of whitefly in crops. Our results will contribute to genetic improvement programs for brassicas focusing on resistance to B. tabaci MEAM1. School of Agriculture Department of Crop Protection São Paulo State University Luiz de Queiroz College of Agriculture Department of Entomology and Acarology University of São Paulo School of Agriculture Department of Crop Protection São Paulo State University CAPES: 001 CNPq: 305991/2020

Made available in DSpace on 2022-05-01T12:40:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-05-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) The introduction of Bemisia tabaci Mediterranean (MED) (Gennadius) (Hemiptera: Aleyrodidae) (Biotype Q) into Brazil has attracted the attention of farmers and the scientific community as this species has a high capacity for infestation and high tolerance to conventional insecticides. As an alternative to chemical control, botanical derivatives stand out as a valuable tool for integrated pest management (IPM). In this context, this work evaluated for the first time the bioactivity of essential oils of Piper marginatum Jacq. (Piperaceae) (PM-EO) and Mansoa alliaceae (Lam.) A.ww H. Gentry (Bignoniaceae) (MA-EO) against B. tabaci MED. First, concentration-mortality bioassays were performed to estimate the lethal concentrations (LCs) on nymphs of B. tabaci MED. The LC50s and LC90s were tested in multi-choice assays (repellency and oviposition deterrence) and no-choice assays (ovicidal effects and infestation ability). Finally, assays were carried out in a greenhouse to check the efficiency of the essential oils under semifield conditions. The major compounds identified in PM-EO were (E)-methyl eugenol (34.7%) and (Z)-methyl eugenol (27.5%), while diallyl trisulfide (52.8%) and diallyl disulfide (33.9%) were the major compounds in MA-EO. The EOs were toxic against nymphs in the laboratory and greenhouse and showed ovicidal effect and repellent action. The EOs also reduced oviposition and inhibited the colonization by B. tabaci MED. Our results reveal two promising sources of botanical pesticides to control B. tabaci MED. These compounds can cause lethal and sublethal effects in all insect life stages, increasing the control efficiency. Department of Crop Protection School of Agriculture São Paulo State University, SP Department of Chemistry Faculty of Philosophy Sciences and Letters University of São Paulo, SP Exact Sciences and Technology Institute Federal University of Amazonas, AM Department of Crop Protection School of Agriculture São Paulo State University, SP CNPq: 305991/2020-5

Made available in DSpace on 2020-12-10T17:01:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-11-29 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) This study aimed to evaluate the bioactivity of ethanolic extracts from different parts of some Annona species (A. montana, A. muricata and A. sylvatica) against T. absoluta. In the initial screening, the ethanolic extracts from leaves and seeds of A. muricata promoted pronounced lethality and growth inhibition of T. absoluta larvae by means of residual contact and translaminar action. However, these extracts did not affect its biology, oviposition in choice and no-choice tests, as well as egg viability. Afterwards, the crude ethanolic extracts of leaves and seeds from A. muricata were submitted to liquid-liquid partitioning, and their respective fractions were evaluated against T. absoluta larvae. These procedures disclosed the hydroalcoholic fraction from A. muricata seeds and both the ethyl acetate and dichloromethane fractions from its leaves as the most active against T. absoluta larvae. Then, proton nuclear magnetic resonance (H-1 NMR) experiments were performed aiming to identify the main constituents present in these fractions. The chemical analyses of each NMR spectrum revealed that A. muricata bioactive fractions presented acetogenins as major compounds. Moreover, a formulated ethanolic extract from A. muricata seeds presented similar bioactivity against T. absoluta larvae in both laboratory and greenhouse bioassays when compared with two commercial botanical insecticides (Anosom(TM) 1 EC and Azaamax 1.2 EC). Therefore, the seeds from A. muricata, discarded during the process of its fruit pulp extraction, are a potential source of bioactive acetogenins to formulate botanical insecticides to control populations of T. absoluta in tomato crops, mainly in organic production systems. Sao Paulo State Univ, Sch Agr, Dept Crop Protect, Botucatu, SP, Brazil Univ Sao Paulo, ESALQ, Luiz de Queiroz Coll Agr, Dept Entomol & Acarol, Piracicaba, SP, Brazil Fed Univ Sao Carlos UFSCar, Dept Chem, Nat Prod Lab, Sao Carlos, SP, Brazil Agr Res & Rural Extens Co Santa Catarina, EPAGRI, CEPAF, Res Ctr Family Agr, Chapeco, SC, Brazil Sao Paulo State Univ, Sch Agr, Dept Crop Protect, Botucatu, SP, Brazil

The corn leafhopper Dalbulus maidis (DeLong & Wolcott) (Hemiptera: Cicadellidae) poses a serious threat to the crop, causing direct and indirect damage to plants. The present study aimed to investigate the possible expression of resistance by antixenosis and/or antibiosis against D. maidis in 11 corn genotypes [8 non-Bt (60XB14, 90XB06, XB 9003, XB 8018, XB 8010, IAC 8390, IAC 8046, and IAC AIRAN) and 3 Bt (XB 7116 Bt, XB 8010 Bt, and DKB 310 Bt)] previously selected in a greenhouse. Initially, no choice preference tests for oviposition were performed to characterize the expression of antixenosis. To characterize the expression of antibiosis/antixenosis, the insects were confined to leaves of different genotypes to assess the following parameters: duration of each nymphal stage, nymphal period, viability per instar, total viability, and adult longevity. Additionally, morphological and physical analyses of the genotypes were carried out to establish correlations with the resistance categories. The genotypes 90XB06, IAC 8390, XB 9003 and DKB 310 PRO3 expressed antixenosis against leafhoppers, reducing insect oviposition. The genotypes 60XB14, 90XB06, IAC 8046, XB 8018 and IAC 8390 expressed antibiosis and/or antixenosis against leafhoppers, reducing nymphal viability. The hardness of the ribs is probably associated with the resistance of some of the evaluated genotypes and is an important morphological defense against leafhoppers. The results of this study are novel and can aid in corn-breeding programs focused on plant resistance to sucking insects, with relevant impacts on the integrated pest management of the crop.

Made available in DSpace on 2022-04-29T08:35:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 The whitefly Bemisia tabaci(Gennadius) MEAM 1 is one of the main insect species that colonize tomato plants and cause direct and indirect damage. The use of botanical derivatives may be a valuable method of insect control to reduce the inappropriate use of synthetic insecticides on crops. In this study, we evaluated the bioactivity of ethanolic extracts prepared from Annonaceae species compared to that of the commercial insecticides based on acetogenins (Anosom® 1 EC, anonine 10,000 mg L−1) and thiamethoxam (Actara® 250 WG) on eggs, nymphs, and adults of the whitefly in tomato. Initially, the effects of the ethanolic seed extracts of Annona mucosa (Jacq.), Annona muricata L., and Annona sylvatica A.St.-Hil on adult insect behavior were evaluated. The rates of infestation and oviposition deterrence indicated the inhibitory effects of the extract of A. muricata (500 mg L−1). Then, the possible systemic effects of the extracts were evaluated; however, no effects on nymphal development or insect viability were observed. The LC50 and LC90 of the ethanolic extract of A. mucosa seeds at 500 mg L−1 (10.83 and 200.24 mg L−1, respectively) were estimated and were used in ovicidal tests and compared to positive (Actara® 250 WG and Anosom® 1 EC), and negative controls (water: acetone, 1:1 v/v). At LC90, fewer eggs (35.00%) had hatched at 13 days after application than in the other treatments. The results of this study demonstrate the potential use of botanical derivatives of Annona spp. for the management of B. tabaci MEAM 1 in tomato. Dept of Crop Protection School of Agriculture São Paulo State Univ (FCA / UNESP) Research Center for Family Agriculture Agricultural Research and Rural Extension Company of Santa Catarina (CEPAF/EPAGRI) Dept of Entomology and Acarology “Luiz de Queiroz” College of Agriculture Univ of São Paulo (ESALQ/USP) Dept of Crop Protection School of Agriculture São Paulo State Univ (FCA / UNESP)

Made available in DSpace on 2021-06-26T00:47:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-09-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Forestry Science and Research Institute -IPEF The red gum lerp psyllid, Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae), is considered one of the most important pests of Eucalyptus worldwide. Since its detection in Brazil in 2003, the insect has caused defoliation in forests, twig dieback and sooty mold. Several types of management were evaluated, but few studies focused on the search for resistant Eucalyptus species and hybrid clones. The present study aimed to assess the biological performance of G. brimblecombei on E. camaldulensis, E. urophylla, and E. grandis and on the hybrids E. grandis x E. camaldulensis (1277 and 3025), E. urophylla x E. camaldulensis (VM-01), and E. urophylla x E. grandis (C-219, H-13, GG-100 and I-144), in order to determine resistance mechanisms. Under laboratory conditions (T= 26 +/- 2 degrees C; RH = 60 +/- 10%; photoperiod = 12 h), psyllids on each of the ten Eucalyptus genotypes were evaluated daily until adult emergence. Genotypes C-219 and H-13 (E. urophylla x E. grandis) exhibited high levels of antibiosis and/or antixenosis (non-preference) resistance to G. brimblecombei, drastically reducing nymph viability (mortality > 80%). In turn, genotypes 3025 (E. grandis x E. camaldulensis) and E. camaldulensis were highly susceptible to the biological development of red gum lerp psyllids. Our results may contribute to genetic improvement programs aimed at obtain G. brimblecombei resistant Eucalyptus genotypes. Univ Fed Goias UFG, Goiania, Go, Brazil Univ Estadual Paulista UNESP, Botucatu, SP, Brazil Suzano Papel & Celulose, Itapetininga, SP, Brazil Univ Estadual Paulista UNESP, Botucatu, SP, Brazil FAPESP: 2009/50815-5

Made available in DSpace on 2020-12-12T01:38:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-07-01. Added 1 bitstream(s) on 2021-07-15T14:37:56Z : No. of bitstreams: 1 S0102-05362020000300280.pdf: 718270 bytes, checksum: ab3fd6bdcade0ffa2f691924d7f74ce6 (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Bemisia tabaci (Hemiptera: Aleyrodidae) is a polyphagous insect that causes direct and indirect damage on tomato. Spraying with synthetic insecticides is one of the main control tools for the whitefly; however, the abusive use of this tool can impact the environment and human beings. In this study we evaluated the bioactivity of extracts from plant species from Asteraceae and Meliaceae families on B. tabaci biotype B in tomato. A preliminary bioassay evaluated the effects of the extracts at 2% (w/v) on infestation and oviposition of this whitefly. Then, the nymphicidal and ovicidal effects of the chloroformic extract of Trichilia pallida-TP-Cl at six concentrations were performed. Finally, the TP-Cl LC50 was estimated. All extracts were repellent to the whitefly, except that ones from T. pallida (ethanolic) and Melia azedarach (hexanic), considered neutral at 24 h. All the extracts caused deterrence of oviposition. All concentrations of TP-Cl revealed nymphicidal activity and the highest ones provided the lowest egg viability averages. The estimated LC50 was 0.0955%. These results provide evidence for the potential of the extracts to be used as alternative control agents of B. tabaci biotype B in tomatoes. Universidade Estadual Paulista (UNESP) Universidade de São Paulo (USP) Escola Superior de Agricultura “Luiz de Queiroz” (ESALQ) Universidade Estadual Paulista (UNESP) FAPESP: 2007/50688-8 CNPq: 303892/2016-1

Made available in DSpace on 2020-12-10T17:35:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-06-22 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Bemisia tabaci(Genn.) (Hemiptera: Aleyrodidae) is a major pest of several agricultural crops, being vector of an extreme number of viruses. The broad variety of host plants, high adaptability and evolution of resistance to insecticides evidence the difficult in the management ofB. tabaciin the agriculture system. Host plant resistance is a valuable and sustainable method of insect management. To date, few studies have characterized the resistance of cucumber (Cucumis sativusL.) genotypes toB. tabaci, although this plant is one of the most preferred host of this hemipteran. The objective of this study was to assess the resistance of 60 cucumber genotypes againstB. tabaciin greenhouse and laboratory conditions and to characterize the mechanisms of resistance involved based on morphological and physical plant parameters. Initially, 12 genotypes were selected in a screening bioassay. In general, 'IAC-1214' expressed high levels of antixenosis to the insect, causing low attractiveness to adults and non-preference for oviposition and colonization. 'Wellington' prolonged the development of the insect and provoked low levels of adult emergence, expressing levels of antibiosis. Antibiosis and/or antixenosis were detected in 'IAC-1201', 'Campeiro', 'Japones', and 'IAC-1311', while antixenosis was detected in 'Kyria' and 'IAC-1175'. The density of the trichomes and the color of the leaves are described and discussed here. The selected genotypes present potential application in integrated programs that focus on reducing populations ofB. tabaciin the agricultural system and in breeding programs aiming to explore resistant genotypes against the insect. Agron Inst Campinas, BR-13012970 Campinas, SP, Brazil Univ Sao Paulo, Luiz de Queiroz Coll Agr, Dept Entomol & Acarol, BR-13418900 Piracicaba, SP, Brazil Sao Paulo State Univ, Coll Agron Sci, Dept Crop Protect, BR-18610307 Botucatu, SP, Brazil Sao Paulo State Univ, Coll Agron Sci, Dept Crop Protect, BR-18610307 Botucatu, SP, Brazil

Background. Zabrotes subfasciatus (Boh., 1833) (Coleoptera: Chrysomelidae: Bruchinae), is considered one of the most important pest of stored beans. Objective. This study reports the possible toxicity and repellence of powders prepared from eight plant species against the Mexican bean weevil in two formulations (dry powder and sachets). Methodology. A 10 ˟ 2 factorial design (10 species ˟ 2 formulations) with 8 repetitions in a completely randomized design was employed. Pots with no powder were used as a negative control, and a pyrethroid insecticide [K-Obiol® 2 DP (deltamethrin, 0.5 g a.i. ton-1)] was applied as a positive control. Results. A mixture of powdered Chenopodium ambrosioides L., Ruta graveolens L. and Mentha pulegium L. added to bean grains was confirmed to be toxic to Z. subfasciatus adults with promising grain protector properties. C. ambrosioides powder had the same effect when in a sachet. A mixture of powdered R. graveolens, M. pulegium and C. ambrosioides with the beans inhibited weevil oviposition. The same effect was achieved for M. pulegium and C. ambrosioides in sachets. A mixture of powdered C. ambrosioides, M. pulegium, R. officinalis and R. graveolens repelled Z. subfasciatus adults from bean grains. Implications. This is the first report of using botanical derivatives by means of sachets or dry formulations, a pre-commercial purpose for aromatic plants with insecticidal/repellent activities. Conclusions. Sachets containing powdered C. ambrosioides and M. pulegium efficiently controlled the Mexican bean weevil in stored beans and constitute an useful tools for domestic grain stock or post-harvest management of organic grains.

Made available in DSpace on 2020-12-10T17:30:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-03-01 The cabbage aphid, Brevicoryne brassicae (L.) (Hemiptera: Aphididae), is distributed throughout the tropical and subtropical areas of the world. The main crops attacked by B. brassicae are cabbage, collard greens, broccoli, Brussels sprouts, and cauliflower. To survive the attack of pest insects, plants have evolved various resistance mechanisms that may affect pest feeding behavior. The use of electronic monitoring through EPG (electrical penetration graph) can help characterize and distinguish the resistance mechanisms involved. This study evaluated the feeding behavior of B. brassicae in eight genotypes of collard greens, Brassica oleraceae L. var. acephala (Brassicaceae), exhibiting antixenosis and/or antibiosis resistance to this insect. Possible correlations were established between the glucosinolate levels, the hardness, and the epicuticular wax on the leaves vs. aphid feeding behavior. On the genotypes 22V, 5E, and 27VA, for which many 'potential drop' waves were performed, aphid development was slower, indicating antixenosis as resistance type. Aphids on the genotypes 22V and 24X required more time until accessing the phloem, also suggesting antixenosis as resistance category. Genotypes 22V and PE had hard leaves, which also points at antixenosis. Genotypes 20T and HS had higher total wax and wax mg(-1). Feeding parameters on ARI and 24X were similar to those observed on HS; antibiosis is likely to be the predominant resistance category of this germplasm. Because HS was considered as a susceptible standard genotype in this study, a higher gluconapin amount indicates that this compound does not influence cabbage aphid feeding behavior. The present study confirms that analysis of the physical and chemical aspects of collard greens genotypes by the EPG technique can provide a useful approach for the study of plant resistance to cabbage aphids. Sao Paulo State Univ, Sch Agr, Dept Crop Protect, BR-18610034 Botucatu, SP, Brazil Agron Inst Campinas, BR-13012970 Campinas, SP, Brazil Univ Sao Paulo, Dept Phys & Chem, Sch Pharmaceut Sci, BR-14040903 Sao Paulo, SP, Brazil Sao Paulo State Univ, Sch Agr, Dept Crop Protect, BR-18610034 Botucatu, SP, Brazil

Made available in DSpace on 2022-04-29T08:37:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-03-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Combinations of essential oils (EOs) are promising alternatives for pest management in storage grains. A high diversity of compounds in EOs and EO mixtures can increase their toxicity. Additionally, EOs can be useful in insecticide resistance programs. For this reason, we evaluated the fumigant toxicity and repellent effects of six essential oils (Dysphania ambrosioides, DA; Pelargonium graveolens, PE; Piper arboreum, PA; Piper diospyrifolium, PD; Piper gaudichaudianum, PG; and Piper tuberculatum, PT) separately and in binary combinations against adults of Sitophilus zeamais (the maize weevil). First, the insecticidal activity of all possible combinations of the six EOs were assessed. Next, the concentrations needed to cause 50% and 90% mortality (LC50 and LC90, respectively) in the S. zeamais population were determined for the most toxic EOs and mixtures. After that, the synergistic effect of the mixtures was also verified. Finally, the most toxic treatments were assessed to determine the time required to cause mortality of 50% of the population and check the repellent effects on S. zeamais. The binary mixtures of DA and PE, PT, PG, PD, and PA were the most toxic against S. zeamais. The LC50 and LC90 values for these treatments ranged between 1.77 and 2.25 μL L−1 and from 2.42 to 7.64 μL L−1, respectively. The mixtures were more toxic than the EOs tested separately, which indicates the occurrence of synergistic effects. All treatments caused mortality of 50% of the population of S. zeamais in less than 42 h of exposure. In addition, the combinations DA + PE, DA + PT, DA + PG, and DA + PA were repellent to S. zeamais. Based on these results, we conclude that the mixtures of EOs evaluated in this study are highly promising for the control of S. zeamais populations and can also be used for resistance management of this species. Departmento de Proteção de Plantas Faculdade de Ciências Agronômicas Universidade Estadual Paulista Departmento de Química Faculdade de Filosofia Ciência e Cartas de Ribeirão Preto Universidade de São Paulo, Ribeirão Preto Departmento de Proteção de Plantas Faculdade de Ciências Agronômicas Universidade Estadual Paulista CNPq: 303892/2016-1

Made available in DSpace on 2019-10-04T12:36:48Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-03-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Bemisia tabaci (Gennadius) biotype B (Hemiptera: Aleyrodidae) has developed resistance to numerous conventional insecticides, which has led us to investigate the toxicity of ten dihydrobenzofuran- (DBN) and benzofuran-type (BN) neolignans structurally related to conocarpan against second instar B. tabaci nymphs. At concentrations higher than 5mg/L, most of the tested compounds killed 100% of B. tabaci biotype B nymphs 6days after spraying. The contact toxicity of compounds 2 ((+/-)-trans-dehydrodiferulate dimethyl ester), 3 ((+/-)-4-O-methyl-trans-dehydrodiferulate dimethyl ester), 5 ((+/-)-4-O-acetyl-trans-dehydrodiferulate dimethyl ester), 6 ((+/-)-7,8-dihydro-trans-dehydrodicoumarate dimethyl ester), 8 ((+/-)-4-O-methyl-7,8-dihydro-trans-dehydrodiferulate dimethyl ester), and 10 ((+/-)-7,8-dihydro-7,8-dehydro-trans-dehydrodicoumarate dimethyl ester) was higher than the contact toxicity of pyriproxyfen at a concentration of 75mg/L, which was used as positive control. Repellent (compounds 2 and 7 ((+/-)-7,8-dihydro-trans-dehydrodiferulate dimethyl ester) and oviposition deterrent (compounds 2, 3, and 7) effects were observed for adult whiteflies exposed to leaves sprayed with DBNs for 24 and 48h, respectively. These results suggest that DBNs have potential application in the development of effective pest management compounds. Univ Estadual Paulista, Fac Ciencias Agron Botucatu, Dept Protecao Vegetal, Botucatu, SP, Brazil Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Quim, Ribeirao Preto, SP, Brazil Univ Estadual Paulista, Fac Ciencias Agron Botucatu, Dept Protecao Vegetal, Botucatu, SP, Brazil FAPESP: 2013/20094-0 FAPESP: 2016/16957-0

Made available in DSpace on 2018-11-26T16:03:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-06-01 Nacional Council for Scientific and Technological Development Aphis glycines Matsumura (Hemiptera: Aphididae) is a serious pest of soybean in North America. Plant resistance is a valuable tool for the management of this pest, and a better understanding of the interactions between aphid and soybeans expressing varying levels and different categories of resistance can assist in the development of aphid resistant or tolerant genotypes. The electrical penetration graph (EPG) technique was used to evaluate the feeding behavior of A. glycines (biotype 1) on 4 soybean genotypes: (1) 'Dowling' (contains Rag1 gene and exhibits antibiosis); (2) PI 200538 (contains Rag2 gene and exhibits antixenosis); (3) KS4202 (exhibits tolerance); and (4) 'D76RR' (susceptible to aphid). Aphids spent shorter periods in the sieve element phase on 'Dowling' and exhibited a greater number of pathway phases, non-probing events, and a longer time in non-probing events in PI 200538 and 'Dowling.' For 'SD76RR' and KS4202, aphids demonstrated more sustained phloem ingestion, spent shorter time in non-probing events, and exhibited fewer pathway phases and potential drops. These results indicate that resistance factors are present in the phloem of 'Dowling.' For PI 200538, it is suggested that antixenotic factors are involved in resistance to A. glycines. Because KS4202 is tolerant to biotype 1 of A. glycines, the suitability of this genotype was expected already. This study provides important data that contribute to the understanding of how soybean aphids (biotype 1) feed on soybean genotypes with various aphid resistant genes and categories. In addition to assisting in the distinction between resistance categories, these results are useful in soybean breeding programs focusing on developing genotypes with greater resistance to insects. Sao Paulo State Univ, Coll Agron Sci, Dept Crop Protect, BR-18610307 Botucatu, SP, Brazil Univ Nebraska, Dept Entomol, 103 Entomol Hall, Lincoln, NE 68583 USA Univ Sao Paulo, Luiz de Queiroz Coll Agr, Dept Entomol & Acarol, BR-13418900 Piracicaba, SP, Brazil Univ Nebraska Lincoln, Haskell Agr Lab, Concord, NH 68728 USA Sao Paulo State Univ, Coll Agron Sci, Dept Crop Protect, BR-18610307 Botucatu, SP, Brazil Nacional Council for Scientific and Technological Development: 200096/2011-7

The whitefly Bemisia tabaci is one of the most important pests of solanaceous crops worldwide, mainly due to its ability to transmit different viruses, including begomoviruses. Tomato severe rugose virus (ToSRV) is the prevalent begomovirus in southeastern and central Brazil, and affects economically important vegetable crops such as tomato and pepper. Here we evaluated 36 pepper accessions comprising four species (Capsicum annuum, C. frutescens, C. chinense and C. baccatum) for ToSRV and B. tabaci resistance, through free-choice and non-choice tests. The accessions IAC-1544 (C. frutescens), IAC-1545 and 1549 (C. chinense), IAC-1551, 1566 and 1579 (C. annuum) were infected by ToSRV but did not show any symptoms. Among them, IAC-1544, IAC-1545, IAC-1551 and IAC-1579 displayed significant differences in whitefly egg-laying preference in the free-choice test. In the non-choice test, IAC-1544, IAC-1545 and IAC-1579 displayed similar reaction, being unattractive to the insects and exhibiting reduced oviposition rates. Low survival of nymphs and high mortality were observed in accessions IAC-1544, IAC-1545, IAC-1549, IAC-1551, IAC-1566 and IAC-1579, suggesting the involvement of antibiosis mechanisms. The accessions IAC-1544, IAC-1545 and IAC-1579 could be classified as good sources of resistance to both ToSRV and B. tabaci.

Made available in DSpace on 2018-11-26T17:51:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-01-01. Added 1 bitstream(s) on 2021-07-15T14:32:15Z : No. of bitstreams: 1 S0006-87052018000100124.pdf: 5004778 bytes, checksum: 69432738ba34a2359174421f5de14e70 (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) The soybean looper Chrysodeixis includens is one of the main defoliating pests of soybean cultures in Brazil. This work aimed to evaluate the effect of offering different soybean genotypes to this insect to verify the occurrence of antixenosis. In a greenhouse, assays were carried out to determine the attractiveness of C. includens adults given free-choice tests. This experiment used a randomized block design with five replicates. A second experiment assessed oviposition preference using no-choice tests, employing a completely randomized design with five replicates. Seventeen soybean cultivars were used; several of these had previously been reported as carriers of resistance to more than one species of insect. In the laboratory, a morphological analysis was carried out by quantifying the number of trichomes on leaf surfaces and evaluating the color of the leaf blade of the germplasm. In the attractiveness assay, genotypes 'IAC 19', 'IAC 18', 'IAC 23', L1-1-01, PI 274453, PI 229358, PI 171451, 'IAC 100', 'IAC 24', 'IAC 17' and IAC 74-2832 were classified as repellents. In the oviposition preference experiment, PI 171451, PI 274453, 'IAC 18', L1-1-01 and 'IAC 23' showed the fewest eggs. The high density of trichomes presented by the genotypes PI 227687 and PI 274453 stand out as a possible C. includens resistance factor. The genotype L1-1-01 presented intermediate luminosity (L*) and more intense green (a*) and yellow (b*) colors compared to other genotypes. There was no correlation between oviposition and trichome density or leaf coloration. Embrapa Agr Oeste Entomol, Dourados, MG, Brazil Univ Estadual Paulista, Fac Ciencias Agron, Dept Protecao Vegetal, Botucatu, SP, Brazil Inst Agron Estado Sao Paulo, Ctr Fitossanidade, Campinas, SP, Brazil Univ Estadual Paulista, Fac Ciencias Agron, Dept Protecao Vegetal, Botucatu, SP, Brazil

Made available in DSpace on 2018-11-26T17:48:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-04-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) The stink bug complex includes some of the most important soybean pests worldwide. Among these insects, Piezodorus guildinii (Westwood) (Hemiptera: Pentatomidae) is known for the severe damage it can cause and for its resistance to chemical management. Host plant resistance is considered as an important tool in the management of these pests. In particular, plant flavonoids, such as genistein and rutin, have been identified as compounds that might negatively affect the development of some pests; however, the effects of these compounds on some stink bug species are still unclear. We tested the resistance of soybean genotypes by evaluating the growth and survival of P. guildinii under laboratory conditions. In addition, the amounts of genistein and rutin were quantified in both infested and non-infested genotypes. The PI 274453, PI 274454, PI 227687, PI 229358, 'IAC 100', and 'IAC 19' genotypes showed antibiosis to P. guildinii. The genistein and rutin flavonoids appear to play a role in the resistance of these genotypes against P. guildinii; specifically, PI 274453, PI 274454, and 'IAC 100' showed induced resistance against the insect. Other defence mechanisms or flavonoids might be involved in resistance in the L1-1-01 and PI 171451 genotypes. These results help us better understand the role of flavonoids in plant defence mechanisms and might prove useful in breeding programmes aimed at developing resistant soybean plants. Univ Sao Paulo, Dept Entomol & Acarol, Luiz de Queiroz Coll Agr, BR-13418900 Sao Paulo, Brazil Sao Paulo State Univ, Dept Crop Protect, Coll Agron Sci, BR-18610307 Botucatu, SP, Brazil Sao Paulo State Univ, Dept Hort, Coll Agron Sci, BR-18610307 Botucatu, SP, Brazil Agron Inst Campinas, Phytosanitary Ctr, BR-13012970 Sao Paulo, Brazil Sao Paulo State Univ, Dept Crop Protect, Coll Agron Sci, BR-18610307 Botucatu, SP, Brazil Sao Paulo State Univ, Dept Hort, Coll Agron Sci, BR-18610307 Botucatu, SP, Brazil

BACKGROUND Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is one of the major pests of maize and is in the same feeding guild as the noctuid pests Helicoverpa zea (Boddie) and Helicoverpa armigera (Hubner), recently reported in South and North America. The intraguild interactions of these species were assessed in laboratory and field conditions by determining the survival of larvae in interaction scenarios with non-Bt maize silks and ears. Moreover, a video tracking system was utilized to evaluate behavioral parameters during larval interactions in scenarios with or without food. RESULTS In intraguild interactions, S. frugiperda had greater survival (55–100%) when competing with Helicoverpa spp. in scenarios where larvae were the same instar or when they were larger (fourth versus second) than their competitor. Frequency and time in food of S. frugiperda larvae were negatively influenced by interactions. Larvae of S. frugiperda moved shorter distances (less than 183.03 cm) compared with H. zea. CONCLUSION Overall, S. frugiperda had a competitive advantage over Helicoverpa spp. This study provides significant information regarding noctuid behavior and larval survival during intraguild interactions, which may impact pest prevalence and population dynamics, thereby affecting integrated pest management and insect resistance management of these species in maize. © 2017 Society of Chemical Industry

Made available in DSpace on 2018-11-26T17:42:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-12-01 The bean weevil Acanthoscelides obtectus (Say, 1831) (Coleoptera: Bruchidae) is one of the most serious pests of stored beans worldwide because of the damage it causes to grains within warehouses. The use of resistant genotypes may offer a control strategy for this pest. In the current study, we screened common bean genotypes of Andean American and Mesoamerican origin in laboratory and greenhouse bioassays to select the most promising beans for resistance to the bean weevil. In the laboratory, we evaluated number of eggs, period of development (egg-adult), number of emerged adults, dry weight of adults, and weight of consumed grains. In the greenhouse, number of pods per plant and number of grains per pod were evaluated. We also assessed the percentages of damaged pods per plant and damaged grains per pod. Combining the results obtained in the laboratory and greenhouse assays, the common bean genotypes Arc.1, Arc.2, Arc.1S, Arc.5S, and Arc.3S were identified as resistance expressing antibiosis against A. obtectus. The lowest percentages of damaged pods were found in the Arc.1 and Arc.1S genotypes, and their resistance to damage was apparently morphological (antixenotic) because they possessed structures that prevented contact between larvae and grains. The use of resistant genotypes in combination with other techniques may improve management of the weevil. Additionally, the resistant genotypes identified here can be used in breeding programs to develop common bean lines with resistance to A. obtectus. Sao Paulo State Univ, Dept Crop Protect, Coll Agron Sci, BR-18610307 Botucatu, SP, Brazil Sao Paulo State Univ, Dept Plant Protect, Coll Agron & Vet Sci, BR-14884900 Jaboticabal, SP, Brazil Sao Paulo State Univ, Dept Crop Protect, Coll Agron Sci, BR-18610307 Botucatu, SP, Brazil Sao Paulo State Univ, Dept Plant Protect, Coll Agron & Vet Sci, BR-14884900 Jaboticabal, SP, Brazil

Made available in DSpace on 2018-11-26T17:40:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-04-01. Added 1 bitstream(s) on 2021-07-15T14:32:05Z : No. of bitstreams: 1 S0006-87052017000200257.pdf: 748267 bytes, checksum: 91b6340fc717368e5e2b6f5309d65538 (MD5) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Productivity Scholarship in Research Some species of pentatomids stink bugs have global economic importance, damaging various plant species during the vegetative and reproductive phases. Dichelops melacanthus (Dallas) (Hemiptera: Pentatomidae), known as the green-belly stink bug, is part of the soybean stink bug complex in Brazil and has increasing importance in crops, with potential to reduce crop yield. This polyphagous stink bug has been registered in 29 plant species belonging to 10 plant families which include cultivated and non-cultivated plants. Plant resistance is a valuable tool in integrated pest management and may reduce insect populations below economic injury level. This study characterized the resistance of 17 soybean genotypes to the green-belly stink bug. All of materials affected the biological performance of the green-belly stink bug, but PI 227687; 'IAC 100'; PI 171451; IAC 78-2318; D 75-10169; IAC 74-2832; 'IAC 23' and 'IAC 24' caused mortality above 80% in the second instar. 'IAC 17'; 'IAC 18'; PI 171451; PI 274454; 'Conquista' and 'IAC 19' decreased the longevity of adults of D. melacanthus, showing the same mechanism of resistance. PI 227687 did not allow any insects to complete the immature stage. These results are unprecedented for the species D. melacanthus and can assist breeding programs that focus on resistance to members of the stink bug complex in soybean. Univ Estadual Paulista, Fac Ciencias Agron, Dept Protecao Vegetal, Botucatu, SP, Brazil Univ Sao Paulo, Escola Super Agr Luiz de Queiroz, Dept Entomol & Acarol, Piracicaba, SP, Brazil Inst Agron Estado Sao Paulo, Ctr Fitossanidade, Campinas, SP, Brazil Univ Estadual Paulista, Fac Ciencias Agron, Dept Protecao Vegetal, Botucatu, SP, Brazil

This study aimed to evaluate the biotic potential and life table of individuals of Helicoverpa armigera (Hubner) from different host plants (citrus, corn, and cotton) and Brazilian states (Sao Paulo, Distrito Federal, and Bahia) in artificial diet, under laboratory conditions (25 ± 1°C, 70 ± 10% RH, 14 h photophase). The longevity, pre-, post- and oviposition periods, fecundity, and fertility of 15 mating pairs per origin were evaluated. We also compared the reproductive parameters of each group of insects (Sao Paulo (SP), Distrito Federal (DF), and Bahia (BA)), including the net reproductive rate (Ro), mean generation time (T), intrinsic rate of increase (r m), and finite rate of increase (λ). Microsatellite analysis from individuals collected in different locations and host plants did not show differences among the parental insects. It was verified that parental progeny collected in cotton fields from Bahia had a higher biotic potential, a higher reproductive rate (Ro), and a better fecundity compared to the insects from remaining regions. The life table charts indicate that the highest values for the reproductive parameters of the Bahia progeny are associated with higher specific fertility, particularly in early adulthood. The greatest biotic potential of the Bahia progeny may be due to increased selection pressure from the insecticide used (organophosphate and pyrethroid) on cotton crops compared to that of other crops, as well due to the massive adoption of Bt cotton-producing areas of that state from 2013 outbreaks.

Made available in DSpace on 2020-12-10T19:57:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01. Added 1 bitstream(s) on 2021-07-15T14:37:18Z : No. of bitstreams: 1 S0006-87052020000100062.pdf: 1326844 bytes, checksum: 6a5f4389a0d93fa13d5268d181416a6a (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) The silverleaf whitefly Bemisia tabaci biotype B is one of the most important sucking pests of common bean, which causes severe damages and requires frequently synthetic insecticides spraying to protect crop productivity. The use of common bean cultivars resistant to whitefly attack is an important strategy within an integrated pest management (IPM) program. The biological development of B. tabaci confined to 17 bean genotypes was evaluated in greenhouse trials to verify the occurrence of antibiosis. Whitefly adults were released on plants of these genotypes to oviposit, afterward the incubation period of eggs, nymphal period, complete development period (egg-adult), and viability of the silverleaf whitefly nymphs were recorded. As main results, genotype CHIP 300 prolonged the developmental period from egg to adult (similar to 10 days) and BRS Estilo, Arcelina 4, IPR Garca, Tybata, CHIP 300, IPR Eldorado, H96A102-1-1-1-52, SCS-202-Guara and CHIB 06 caused nymphal mortality, suggesting high levels of antibiosis and/or antixenosis. These genotypes may be helpful in common bean breeding programs aimed at developing commercial cultivars resistant to B. tabaci biotype B. Univ Estadual Paulista, Fac Ciencias Agron, Dept Protecao Vegetal, Botucatu, SP, Brazil Empresa Pesquisa Agr & Extensao Rural Santa Catar, Ctr Pesquisa Agr Familiar, Chapeco, SC, Brazil Univ Estadual Paulista, Fac Ciencias Agron, Dept Protecao Vegetal, Botucatu, SP, Brazil CAPES: 001 CNPq: 305649/2013-2

Made available in DSpace on 2021-06-25T12:20:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-08-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) The widespread use of transgenic technologies has led to the emergence of insect populations resistant to Bt toxins. Some lepidopteran pest species also appear to naturally have some level of tolerance to certain proteins, such as some species of Spodoptera to Cry1Ac. One of the main strategies to manage resistance is the use of refuge areas, the success of which is in part dependent on larval movement of the target pest. Thus, in order to assess the viability of a refuge strategy addressing Spodoptera eridania Stoll (Lepidoptera: Noctuidae) in Bt soybean, it was evaluated the larval movement across plants in Bt and non-Bt soybean, as well as the larval development and mortality on Bt and non-Bt soybean cultivars. We concluded that apparent S. eridania incomplete resistance resulting from high larval mortality and low adaptability on Bt plants, high larval dispersal, nondirectional larval movement, and random larval spatial dispersion suggest that structured refuge is more suitable than mixed refuge for managing resistance in S. eridania populations. Sao Paulo State Univ, Sch Agr Sci, Dept Plant Protect, Botucatu, SP, Brazil Univ Nebraska Lincoln, Haskell Agr Lab, Concord, NE 68728 USA Sao Paulo State Univ, Sch Agr Sci, Dept Plant Protect, Botucatu, SP, Brazil FAPESP: 2016/19302-5 FAPESP: 2017/08086-2 CNPq: 303892-1 CAPES: 001

Made available in DSpace on 2019-10-06T17:06:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-07-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) This study evaluated the sublethal effects of an ethanolic extract from seeds of Annona mucosa Jacq. (ESAM, major compound rolliniastatin-1) and a botanical insecticide based on the extract of Annona squamosa L. (10,000 mg kg −1 of annonin as the primary active ingredient; Anosom ® 1 EC) at their previously estimated concentrations (LC 50 = 411.55 and 312.08 mg kg −1 , respectively) on the food intake and biological parameters of Helicoverpa armigera (Hübner), an important pest species that was recently introduced to Brazil. In a greenhouse trial, ESAM (as an emulsifiable concentrate formulation) and the botanical insecticide based on the extract of A. squamosa (Anosom ® 1 EC) caused larval mortality and a significant decrease in foliar consumption (>90%) after 168 h of exposure on soybean plants. An evaluation of the indices of food consumption, growth and food utilization indicated that ESAM and Anosom ® 1 EC, when incorporated into artificial media for third instar H. armigera larvae, significantly decreased the growth rate and reduced the efficiency of the conversion of ingested food into biomass. Additionally, ESAM and Anosom ® 1 EC extended the larval stage and significantly reduced the viability of the larval and pupal stages and the average weight of the 24-h-old pupae. In light of these findings, ESAM and the acetogenin-based commercial bioinsecticide Anosom ® 1 EC are potential alternative control measures for H. armigera. Department of Crop Protection School of Agriculture São Paulo State University (FCA/UNESP) Research Center for Family Agriculture Agricultural Research and Rural Extension Company of Santa Catarina (CEPAF/EPAGRI) Department of Entomology and Acarology “Luiz de Queiroz” College of Agriculture University of São Paulo (ESALQ/USP) Department of Crop Protection School of Agriculture São Paulo State University (FCA/UNESP)

Made available in DSpace on 2020-12-10T17:27:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-02-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) is an important pest capable of colonizing several species of cultivated plants, including soybean [Glycine max (L.) Merrill]. The primary management strategy for this insect is chemical control and adoption of Bt plants. However, alternative environmentally friendly strategies should be investigated and adopted as available for sustainable management of this insect pest. One potential underutilized method for insect control is plant resistance. The objective of this study was to categorize resistance (antixenosis and antibiosis) of 22 soybean genotypes on H. armigera in a laboratory setting. A preliminary experiment was conducted using soybean leaves and pods to determine the most promising genotypes for resistance. For each selected genotype, we collected biological parameters, leaf intake, and performed confinement tests. The genotypes PI 227687, PI 274453, PI 274454, PI 229358, PI 171451, 'IAC 17', and 'IAC 19' expressed resistance against H. armigera. Each genotype lowered larval survivorship. The genotypes PI 229358, PI 227687, PI 274453, and PI 274454 expressed resistance by prolonging larval development and reducing fifth-instar larvae weight. 'IAC 19' reduced leaf consumption and lowered the weight of fifth-instar larvae. Antixenosis was found in genotypes PI 227687, PI 274454, and 'IAC 19'. These genotypes might be used in breeding programs focusing on soybean resistance to lepidopterans. Sao Paulo State Univ, Sch Agr Sci, Dept Crop Protect, POB 237, Botucatu, SP, Brazil Sao Paulo State Univ, Luiz de Queiroz Coll Agr, Dept Entomol Phytopathol & Agr Zool, POB 9, Piracicaba, SP, Brazil Campinas Agron Inst, Ctr Phytosanit, POB 28, Campinas, SP, Brazil Mississippi State Univ, Dept Biochem Mol Biol Entomol & Plant Pathol, POB 9775, Mississippi State, MS 39762 USA Sao Paulo State Univ, Sch Agr Sci, Dept Crop Protect, POB 237, Botucatu, SP, Brazil Sao Paulo State Univ, Luiz de Queiroz Coll Agr, Dept Entomol Phytopathol & Agr Zool, POB 9, Piracicaba, SP, Brazil