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Arq. Inst. Biol ; 88: e00572020, 2021. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1349008


Weevil is one of the main pests of stored corn. The adults feed on intact and broken seeds or bran, while the larvae develop by feeding on the inside of the seeds, resulting in a reduction in weight and physiological quality. The objective of this study was to evaluate the effects of Sitophilus zeamais infestation on corn seeds during storage. Corn seeds were infested using insect densities: 0, 36, 72, 108, and 144 individuals per 240 g of seeds. The infested seeds were placed in individualized plastic containers and covered with voile fabric. The seeds were stored for 60 days under laboratory conditions with an average temperature of around 27 °C and relative humidity of 85%. Initially and every 15 days of storage for 60 days, the seeds were evaluated using the parameters: number of S. zeamais individuals, total number of infested seeds, seed weight loss, germination test and seedling emergence in the tray. The population increase of S. zeamais causes a decrease on the physical and physiological quality of stored corn seeds, but the deterioration rate does not increase in the same proportion as the weevil population growth rate.

Zea mays , Weevils/pathogenicity , Seeds , Germination , Agricultural Pests , Insecta , Larva
Arq. Inst. Biol ; 88: e00312020, 2021. ilus, tab
Article in English | LILACS, VETINDEX | ID: biblio-1348973


Phytonematodes are among the main pathogens of the common bean. In general, control practices that aim to control these pathogens have not been regularly adopted in Brazil. The objectives of the present study were to evaluate the occurrence of phytonematodes in dry bean fields in Paraná and São Paulo states and estimate the pathogenicity of Pratylenchus brachyurus to dry bean in glasshouse experiments. Root and soil were sampled for nematode extraction, identification and estimation of population density. Four glasshouse experiments with different initial population densities were carried out to evaluate the effect of P. brachyurus on the growth of dry bean plants. Six species of phytonematodes were detected, namely Helicotylenchus dihystera, P. brachyurus, Pratylenchus crenatus, Meloidogyne javanica, Meloidogyne incognita and Rotylenchulus sp. The spiral nematode H. dihystera was found in all samples and was the most abundant species in both states. The lesion nematode P. brachyurus was also frequent, reaching 94% in Paraná and 100% in São Paulo. The root-knot nematodes and Rotylenchulus sp. were reported only in São Paulo fields (45% and 18% frequency, respectively), and P. crenatus only in Paraná (12%). The most abundant nematode in the soil was H. dihystera, and in roots was P. crenatus. It was demonstrated that densities of 6.66 specimens of P. brachyurus per cm3 of soil provoke visible and measurable root decay. In conclusion, survey data showed low phytonematode densities and pathogenicity tests demonstrated that densities above 6.67 specimens of P. brachyurus per cm3 of soil cause damage to the dry bean roots.

Fabaceae , Nematoda/pathogenicity , Tylenchoidea , Agricultural Pests , Phaseolus
Arq. Inst. Biol ; 88: e00302020, 2021. tab
Article in English | LILACS, VETINDEX | ID: biblio-1348972


Plant parasitic nematodes are major threats to Brazilian and world agriculture. Among them, Pratylenchus brachyurus and Meloidogyne incognita stand out as major pests for several crops, including corn, cotton, soybean among others, which can be components of integrated crop-livestock-forestry systems (ICLFs). In this context, information about the host status of eucalypts (Corymbia spp. and Eucalyptus spp.) to plant parasitic nematodes becomes more relevant in Brazil, due to the use of eucalypts in ICLFs. If tree components used on this system increase the population density of P. brachyurus and M. incognita, it is possible that these pathogens could damage shorter-cycle crops. Since information about the host status of eucalypts to plant parasitic nematodes is scarce, this study evaluated the host status of some eucalypt species to P. brachyurus and M. incognita. Two greenhouse trials were done to evaluate the reproduction of P. brachyurus and one to M. incognita, using some of the most cultivated species and hybrids of eucalypts in Brazil. The population growth of P. brachyurus increased on Corymbia citriodora, Eucalyptus grandis, Eucalyptus dunnii × Eucalyptus urophylla, and E. grandis × E. urophylla after ~90 days of inoculation. Conversely, despite M. incognita reproducing well in the control plants, no individuals were recovered from C. citriodora, E. urophylla and E. grandis × E. urophylla, which were classified as resistant plants. Based on both obtained and available data, M. incognita poses no threat to eucalypt species today. However, P. brachyurus is suggested to be a threat to eucalypts.

Tylenchoidea , Eucalyptus , Nematoda/pathogenicity , Soybeans , Forestry , Agricultural Pests , Zea mays , Gossypium
Arq. Inst. Biol ; 88: e00392020, 2021. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1348967


A very limited amount of information is available in relation both to the residual effect of herbicides destinated to the destruction of cotton stalks and to the time interval required to prevent that development and yield of the following crop be affected. This work aimed to identify the residual activity of herbicides intended to eliminate cotton stalks and to estimate the safety interval (SI) of time for the next cotton sowing. Two trails were simultaneously carried out, the first one for a single application and a second one for the two sequential applications of herbicide treatments, in a 15×5 factorial design organized in randomized complete blocks with four replications. Levels of first factor were constituted by herbicide treatments and the levels of the second factor were composed five periods of time for cotton sowing after herbicide application (0, 30, 60, 90, and 120 days). Herbicides were 2,4-D, glyphosate, saflufenacil, [imazapic + imazapyr], dicamba, fluroxypyr and sulfentrazone. Results provided an indication of residual activity of herbicide treatments in soil and indicated that a single application or two sequential applications of glyphosate + dicamba + saflufenacil have a considerable potential to affect cotton and a period exceeding 100 days for a single application and exceeding 120 days for two sequential applications was necessary. Treatments with 2,4-D and 2,4-D + glyphosate provided the shortest safe interval and may be used for cotton stalk destruction with no risks for the crop sowing after the withdrawal period.

Pest Control/methods , Gossypium , Agricultural Pests , 2,4-Dichlorophenoxyacetic Acid , Herbicides , Insecta
Arq. Inst. Biol ; 88: e00332020, 2021. ilus, tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1348966


Crop pests have negative impacts on yield. This paper proposes a spatiotemporal geostatistical modeling to compare data of adult Syrphidae fly count and corn leaf aphid Rhopalosiphum maidis (Fitch, 1856) colonies in corn crops. The use of a geostatistical model that allows the space-time variation makes the approach more interesting because it is a more complete model. Multiple regression was used to model the trend component for the variable response adult Syrphidae fly count and corn leaf aphid colonies, with the coordinates serving as covariates and the spatiotemporal variations around the deviation are described by a random spacetime residual field. Finally, the prediction map obtained by kriging may be a biological indicator of possible corn leaf aphid colonies in the corn crop. It was possible to verify that the occurrence of the pest provided a significant increase in adult predators and seminatural habitats may favor populations of natural enemies.

Models, Statistical , Zea mays , Diptera , Aphids , Agricultural Pests , Spatio-Temporal Analysis
Arq. Inst. Biol ; 88: e0762019, 2021. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1348963


Maize (Zea mays L.) is among the most cultivated crops in the world and can be affected by several diseases, especially those transmitted by seeds. The study of alternatives to fungicides used for seed treatment has a promising field in essential oils. Thus, this study determined the phytochemical profile of the ethanolic extract from Anadenanthera colubrina (Vell.) Brenan and to evaluate its antifungal activity on the sanitary and physiological quality of maize seeds. The seeds used were of the Jaboatão cultivar, which were submitted to the following treatments: control (untreated seeds), commercial fungicide (dicarboximide) and A. colubrina extract at 200, 400, 600, 800, and 1,000 ppm. The seeds were subjected to sanitary and germination tests in a completely randomized experimental design. Phytochemical prospecting of A. colubrina extract indicated the presence of alkaloids, tannins, flavonoids and saponins, as well as the major compounds lupeol, gallic acid, ferulic acid, catechin and quercetin. The A. colubrina extract reduced the incidence of Aspergillus spp., including Aspergillus niger, Alternaria spp., Curvularia spp. and Fusarium spp. at all concentrations. The highest concentrations (800 and 1,000 ppm) of the A. colubrina extract reduced the incidence of Penicillium spp. and yielded an effective control of Rhizoctonia spp. The extract of A. colubrina did not present phytotoxic effect, guaranteeing the viability and vigor of maize seeds.

Seeds , Zea mays , Penicillium , Aspergillus niger , Rhizoctonia , Oils, Volatile , Agricultural Pests , Alkaloids , Phytochemicals
Arq. Inst. Biol ; 88: e00182020, 2021. ilus
Article in English | LILACS, VETINDEX | ID: biblio-1357872


Sweet potato, Ipomoea batatas (L.) Lam (Convolvulaceae), is an essential crop for food security in developing countries. Euscepes postfasciatus (Fairmaire) (Coleoptera: Curculionidae) is one of the main pests of I. batatas in tropical and subtropical regions. It feeds on the tuberous roots of I. batatas and induces perforations tunnel-shaped with excrement. The objective of this study was to register, for the first time, the occurrence of E. postfasciatus in I. batatas in the municipality of Diamantina, Minas Gerais, Brazil. Individuals of E. postfasciatus were found in the larval, pupal and adult stages feeding on the roots, in the genotypes, Brasilândia Branca, Rubisol, UFVJM01, UFVJM02, UFVJM03, UFVJM04, UFVJM08, UFVJM18, UFVJM91, UFVJM291 and UFVJM526 in a greenhouse at the Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM). Euscepes postfasciatus injuries formed superficial and deep galleries with the presence of excrement and unpleasant odor. The record of E. postfasciatus in I. batatas in the municipality of Diamantina is important to develop local strategies for integrated pest management of the crop in the region.(AU)

Ipomoea , Weevils , Tropical Climate , Coleoptera , Agricultural Pests , Food Supply
Arq. Inst. Biol ; 87: e0062019, 2020. tab
Article in English | LILACS, VETINDEX | ID: biblio-1100114


The soybean looper (Chrysodeixis includens) is an important defoliation pest in crops such as soybean and cotton in Brazil. Its main control tactic is chemical insecticides. Considering the importance of chemical control for this pest, monitoring the susceptibility of C. includens populations is strategic for an efficient Insect Resistance Management. Therefore, the objective of this study was to evaluate the susceptibility levels of C. includens populations in the state of Mato Grosso - Brazil to lufenuron and spinosad. Seven populations were collected in soybean fields around the state. For the bioassays, early L3 larvae were exposed to insecticides using the diet-overlay method. Although the compounds have distinct modes of action, Tangará da Serra population had the highest resistance ratios for lufenuron (11.62) and spinosad (7.84), compared to laboratory population (susceptibility reference). Even with low resistance levels, it is necessary to maintain regional monitoring of C. includens susceptibility to the evaluated insecticides, as well as to extend the range of molecules monitored.(AU)

A lagarta falsa-medideira (Chrysodeixis includens) é uma importante praga desfolhadora em culturas como soja e algodão no Brasil e seu principal método de controle é o uso de inseticidas químicos. Considerando a importância do controle químico para essa praga, o monitoramento da suscetibilidade de populações de C. includens é estratégico para um eficiente programa de Manejo da Resistência de Insetos. Portanto, objetivou-se com este estudo avaliar os níveis de suscetibilidade de populações de C. includens no estado de Mato Grosso, Brasil, aos inseticidas lufenurom e espinosade. Sete populações foram coletadas em cultivos de soja ao longo do estado. Para os bioensaios, lagartas em terceiro ínstar foram expostas aos inseticidas utilizando o método de contaminação superficial de dieta. Embora os compostos apresentem modos de ação distintos, a população de Tangará da Serra obteve as maiores razões de resistência para lufenurom (11,62) e espinosade (7,84) em relação à população de laboratório (referência de suscetibilidade). Apesar dos níveis de resistência terem sido baixos, é necessário manter a manutenção do monitoramento dos níveis de suscetibilidade aos inseticidas avaliados, assim como ampliar a gama de moléculas monitoradas.(AU)

Insecticide Resistance , Insecticides , Lepidoptera , Soybeans , Agricultural Pests , Gossypium , Insecta
Arq. Inst. Biol ; 87: e0352019, 2020. tab
Article in English | LILACS, VETINDEX | ID: biblio-1118058


Spodoptera cosmioides Walker is a polyphagous insecticide-resistant species found in various regions of Brazil. Despite occurring at low densities, it is considered a potential pest of cotton, soybean, and bean crops in the Brazilian cerrado. This work investigated the comparative biology of S. cosmioides in the commercial transgenic cotton NuOPAL (Bollgard I, Evento 531) and the conventional isoline variety DeltaOPAL. The experiment was conducted under laboratory conditions (26 ± 1°C; relative humidity: 70 ± 10%; photoperiod: 12h), using newly-hatched and individualized larvae. We evaluated the duration and viability of immature stages, duration of the biological cycle, pupal weight, sex ratio, percentage of deformed adults and of adults trapped in the pupal case, adult longevity, fecundity, and egg viability. The biological parameters observed showed no significant differences between the two varieties studied, which enabled high consumption, high assimilation, high fecundity, and viability for S. cosmioides.(AU)

Spodoptera cosmioides Walker é uma espécie polífaga, resistente a inseticidas em várias regiões do país e, apesar de ocorrer em baixas densidades, é considerada uma praga potencial para as culturas de algodão, soja e feijão no cerrado. Neste trabalho, estudou-se a biologia comparada de S. cosmioides sobre o cultivar transgênico comercial de algodoeiro NuOPAL (Bollgard I, Evento 531) e sobre o cultivar isolinha convencional DeltaOPAL. O experimento foi desenvolvido em condições de laboratório (26 ± 1°C; UR: 70 ± 10%; fotofase: 12h) a partir de lagartas recém-eclodidas e individualizadas. Foram avaliados a duração e a viabilidade das fases imaturas, a duração do ciclo biológico, o peso de pupas, a razão sexual, a porcentagem de deformação de adultos e de adultos não liberados dos invólucros pupais, a longevidade de adultos, a fecundidade e viabilidade de ovos. Os parâmetros biológicos observados não diferiram significativamente em relação às duas cultivares, que proporcionaram alto consumo, alta assimilação, alta fecundidade e viabilidade à S. cosmioides.(AU)

Spodoptera/growth & development , Gossypium , Pupa , Agricultural Pests
Arq. Inst. Biol ; 87: e0432018, 2020. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1118052


The spotted-wing drosophila, Drosophila suzukii Matsumura, is considered the main insect pest of small fruit in the world. Identifying susceptible hosts is essential to develop management strategies. The aim of this study was to verify the level of D. suzukii infestation in blackberry, blueberry, strawberry, cattley guava and Surinam cherry fruits cultivated in the southern region in Brazil, and to determine the infestation index (II) per fruit. The studies were carried out during two harvests (2015/16 and 2016/17) in three areas with organic cultivation of small fruit. The highest level of D. suzukii natural infestation was observed in blackberry (40 to 65% infestation), and strawberry (approximately 30% infestation) fruits. In contrast, blueberries were less preferred (< 7% infestation). For native fruit of the region (cattley guava and Surinam cherry), it was also verified infestation of the fly, demonstrating they are hosts for multiplication in the off-season periods of the other crops. In relation to II, blackberry and Surinam cherry provided a higher average number of insects per gram of fruit (≈ 1.6 adults of D. suzukii). In contrast, blueberries and cattley guava had the lowest insect ratio per gram of fruit (≈ 0.7 adults per gram). The period between late spring to mid-autumn was considered ideal for the pest occurrence in the field. The knowledge of natural infestation levels is essential for understanding the behavior of the pest in the field, which will assist in the design of management strategies.(AU)

A drosófila-da-asa-manchada, Drosophila suzukii Matsumura, é considerada o principal inseto-praga de pequenos frutos no mundo. A identificação de hospedeiros suscetíveis é essencial para o desenvolvimento de estratégias de manejo. O objetivo deste estudo foi verificar o nível de infestação de D. suzukii em frutos de amoreira-preta, mirtileiro, morangueiro, araçazeiro e pitangueira cultivados na região no sul do Brasil e determinar os índices de infestação (II) por fruto. Os estudos foram realizados durante duas safras (2015/16 e 2016/17) em três áreas com cultivo orgânico de pequenas frutas. O maior nível de infestação natural de D. suzukii foi observado em amora-preta (40 a 65% de infestação) e morango (aproximadamente 30% de infestação). Em contraste, o mirtilo foi menos preferido (< 7% de infestação). Para as frutas nativas da região (araçá e pitanga), também ocorreu infestação da mosca, demonstrando serem hospedeiros potenciais para a multiplicação da praga nos períodos de entressafras. Em relação ao II, amoras e pitangas proporcionaram um maior número médio de insetos por grama de fruto (≈ 1,6 adultos de D. suzukii). Por outro lado, mirtilos e araçás apresentaram a menor relação de insetos emergidos por gramas de frutos (≈ 0,7 adultos por grama). O período entre final da primavera até meados do outono foi considerado ideal para a ocorrência da praga no campo. O conhecimento dos níveis de infestação natural é fundamental para o entendimento do comportamento da praga no campo, o que auxiliará no delineamento de estratégias de manejo.(AU)

Drosophila , Fruit/parasitology , Seasons , Brazil , Agricultural Pests , Vaccinium myrtillus , Morus , Fragaria , Introduced Species , Eugenia
Arq. Inst. Biol ; 87: e0832018, 2020. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1118050


Ichneumonidae are solitary parasitoids that mainly attack larvae and pupae of Lepidoptera, Coleoptera and Hymenoptera, which constitute important agricultural pests. The objective of the present paper was to characterize the assemblage of Ichneumonidae associated to the conventional and organic cultivation of Guarana (Paullinia cupana) crop in Manaus City (Amazonas State, Brazil) with faunistic analysis. The samples were collected at Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA), using Malaise and Moericke traps, between September 2012 and February 2013. We collected 296 specimens of Ichneumonidae, represented by 14 subfamilies, 41 genera and 63 morphospecies. The faunistic analysis revealed the predominance of rare and less frequent genera (54.2% in conventional and 47.1% in organic crop management). Venturia Schrottky was highlighted as superabundant, super frequent and constant (46.4% of the specimens) in conventional cultivation. In organic cultivation, Eiphosoma Cresson (15.6% of the specimens), Venturia (15.1%), Polycyrtidea Viereck (7%), Stethantyx Townes (6%), Enicospilus Stephens and Diapetimorpha Viereck (both 5.5%), Polycyrtus Spinola and Podogaster Brullé (both 5%) were more abundant, more frequent and constant. The observed differences reflect the type of crop management. Considering that organic crop management do not use agrochemicals, there is a greater diversification of the landscape. On the other hand, a reduction in richness and abundance has been observed in conventional crop management, due to its greater alteration and uniformity of the landscape. This study evidences a high number of rare, less frequent and accidental genera, and reveals the predominant groups in each crop cultivation system.(AU)

Ichneumonidae são parasitoides solitários e atacam principalmente larvas e pupas de Lepidoptera, Coleoptera e Hymenoptera, que constituem importantes pragas agrícolas. O objetivo do trabalho foi caracterizar a assembleia de Ichneumonidae associada ao cultivo de guaraná (Paullinia cupana) de manejo convencional e orgânico, em Manaus (Amazonas, Brasil) por meio de análise faunística. As coletas foram realizadas na EMBRAPA, com o uso de armadilhas Malaise e Moericke, entre setembro de 2012 e fevereiro de 2013. Foram coletados 296 exemplares de Ichneumonidae, em 14 subfamílias, 41 gêneros e 63 morfoespécies. A análise faunística revelou predominância de gêneros raros e pouco frequentes (54,2% no manejo convencional e 47,1% no orgânico). Venturia Schrottky destacou-se no manejo convencional como superabundante, superfrequente e constante (46,4% dos exemplares). No manejo orgânico, Eiphosoma Cresson (15,6% dos exemplares), Venturia (15,1%), Polycyrtidea Viereck (7%), Stethantyx Townes (6%), Enicospilus Stephens e Diapetimorpha Viereck (ambos 5,5%), Polycyrtus Spinola e Podogaster Brullé (ambos 5%) foram muito abundantes, muito frequentes e constantes. As diferenças observadas refletem o tipo de manejo da cultura. No manejo orgânico, por não utilizar agroquímicos, há uma maior diversificação da paisagem. Já no manejo convencional há uma redução da riqueza e abundância, por possuir maior perturbação e uniformidade da paisagem. Este estudo evidenciou o elevado número de gêneros raros, pouco frequentes e acidentais e expôs os grupos predominantes em cada sistema de manejo.(AU)

Paullinia/parasitology , Hymenoptera/classification , Lepidoptera/classification , Pupa , Coleoptera , Brazil , Pest Control, Biological , Agricultural Pests , Larva
Arq. Inst. Biol ; 87: e0492019, 2020. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1130102


With the advent of glyphosate-resistant soybean, postemergence applications of the herbicide have become routine. In this way, problems related to the selectivity of glyphosate have been shown to be increasingly intense, due to the use of increased dosages and applications of the herbicide at unrecommended moments. In order to evaluate the agronomic performance of soybean plants subjected to the postemergence application of glyphosate ­ both in isolation and together with Crop+ ­ at different stages and dosage levels, a randomized block design experiment was carried out with two adjacent checks and four repetitions. The treatments consisted of: glyphosate (1296 g·ha-1); glyphosate + Crop+ (1296 + 0.25 g or L·ha-1); glyphosate + Crop+ (1296 + 0.5 g or L·ha-1); glyphosate (2592 g·ha-1); glyphosate + Crop+ (2592 + 0.25 g or L·ha-1); glyphosate + Crop+ (2592 + 0.5 g or L·ha-1); 2 × glyphosate (2 × 1296 g·ha-1); 2 × glyphosate + Crop+ (2 × 1296 + 0.25 g or L·ha-1); 2 × glyphosate + Crop+ (2 × 1296 + 0.5 g or L·ha-1) and Crop+ (0.5 g·ha-1). The phytotoxicity, soil plant analysis development (SPAD) index, height, stand, mass of 100 grains, and yield of the soybean plants were evaluated. The use of Crop+ on soybean plants led to an increase in the SPAD index; the use of Crop+ in association with glyphosate made possible the attenuation of visible symptoms of damage, preventing reductions in crop yield.(AU)

Com o advento da soja resistente ao glifosato, aplicações em pós-emergência da cultura tornaram-se corriqueiras. Dessa forma, problemas relacionados à seletividade desse herbicida mostraram-se cada vez mais intensos, devido ao aumento da dose utilizada e à aplicação em momentos não recomendados. Para avaliar o desempenho agronômico da soja submetida à aplicação de glifosato isolado em pós-emergência e em associação ao Crop+ em diferentes estádios e doses, um experimento foi realizado em delineamento de blocos ao acaso, em esquema de testemunhas duplas adjacentes, adotando-se quatro repetições. Os tratamentos foram constituídos por: glifosato (1296 g·ha-1); glifosato + Crop+ (1296 + 0,25 g ou L·ha-1); glifosato + Crop+ (1296 + 0,5 g ou L·ha-1);glifosato (2592 g·ha-1); glifosato + Crop+ (2592 + 0,25 g ou L·ha-1);glifosato + Crop+ (2592 + 0,5 g ou L·ha-1); 2 × glifosato (2 × 1296 g·ha-1); 2 × glifosato + Crop+ (2 × 1296 + 0,25 g ou L·ha-1); 2 × glifosato + Crop+ (2 × 1296 + 0,5 g ou L·ha-1) e Crop+ (0,5 g·ha-1). Foram avaliados fitointoxicação das plantas de soja, índice SPAD (soil plant analysis development), altura, estande, massa de cem grãos e produtividade. Nos resultados, a utilização de Crop+ em plantas de soja proporcionou o aumento no índice SPAD e, quando o Crop+ foi associado ao glifosato, possibilitou a atenuação dos sintomas visuais de injúrias, prevenindo reduções na produtividade da cultura.(AU)

Soybeans , Herbicide Resistance , Soil , Agricultural Pests , Herbicides
Arq. Inst. Biol ; 87: e0132020, 2020. tab
Article in English | LILACS, VETINDEX | ID: biblio-1130089


This research aimed to evaluate the biological aspects and the feeding behavior of Aphis gossypii in watermelon cultivars submitted to silicon application. The experiment was conducted at the Institute of Education, Agriculture and Environment of the Federal University of Amazonas, Humaitá, Brazil. The experimental design was completely randomized in a 2×3 factorial (with and without silicon; cultivars Crimson Sweet, Fairfax and Charleston), with ten replications. The application of silicic acid (1%) was carried out directly on the substrate using dose equivalent to 1 ton SiO2·ha-1, 25 days after sowing. The rearing of aphids was kept in cucumber plants, cultivar Caipira. Insect biology tests were conducted to evaluate the duration of the prereproductive, reproductive and postreproductive periods, longevity, number of nymphs, and feeding behavior using the honeydew secretion technique. Analysis of variance was performed using the statistical program SISVAR and the means were compared by the F and Scott­Knott test (p ≤ 0.05). The silicon application to watermelon plants affects the reproduction and feeding of A. gossypii. The watermelon plants cultivar Crimson Sweet treated with silicon has high resistance to feeding by A. gossypii.(AU)

Nesta pesquisa objetivou-se avaliar os aspectos biológicos e o comportamento alimentar de Aphis gossypii em cultivares de melancia submetidas à aplicação de silício. O experimento foi conduzido no Instituto de Educação, Agricultura e Ambiente da Universidade Federal do Amazonas, Humaitá, Brasil. Utilizaram-se o delineamento experimental inteiramente ao acaso e o esquema fatorial 2×3 (sem silício e com silício; cultivares Crimson Sweet, Fairfax e Charleston), com dez repetições. A aplicação do ácido silícico (1%) foi realizada diretamente no substrato, com dose equivalente a 1 ton SiO2·ha-1, 25 dias após a semeadura. Os pulgões da criação foram mantidos em plantas de pepino, cultivar Caipira. Foram conduzidos ensaios de biologia do inseto para avaliação da duração dos períodos pré-reprodutivo, reprodutivo e pós-reprodutivo, longevidade, número de ninfas e comportamento alimentar por meio da técnica de secreção de honeydew. Realizou-se a análise de variância dos dados utilizando-se o programa estatístico SISVAR e as médias foram comparadas pelo teste de F e Scott­Knott (p ≤ 0,05). A aplicação de silício em plantas de melancia afeta a reprodução e a alimentação de A. gossypii. Plantas de melancia do cultivar Crimson Sweet tratadas com silício apresentam alta resistência à alimentação por A. gossypii.(AU)

Aphids , Silicic Acid , Gossypium , Citrullus , Pest Control , Agricultural Pests , Cucurbitaceae , Feeding Behavior
Arq. Inst. Biol ; 87: e0782018, 2020. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1130054


The population of the caterpillar Diatraea saccharalis (Lepidoptera: Crambidae) has increased in the crop of sugarcane in recent years. Although the control of this insect is traditionally carried out through biological control, the use of phytosanitary products has still been necessary. Therefore, the goal of this work was to evaluate the performance of different insecticides in sugarcane borer control, as well as the effect on productivity and total recoverable sugar (TRS). The experiment was conducted in a randomized experimental delineation of blocks, with six treatments and four blocks. Treatments consisted of five insecticides and one control group (without application of insecticide). For calculating the D. saccharalis infestation index, monthly samplings were performed every 30 days, for 12 months. After this period, the final D. saccharalis infestation index was evaluated and calculated for each treatment. In order to compare productivity among procedures, four central lines were collected from each plot. Thus, the samples were weighed for the productivity calculation (TCH) and sent to the laboratory for the total recoverable sugar (TRS) analysis. The chloranthraniliprole (350) insecticide provided a lower index of sugarcane borer infestation, in addition to greater productivity when compared to the other insecticides. There was no significant difference in the parameter of total recoverable sugar (TRS) among treatments.(AU)

A população da lagarta Diatraea saccharalis (Lepidoptera: Crambidae) tem aumentado na cultura de cana-de-açúcar nos últimos anos. Apesar do controle deste inseto ser tradicionalmente realizado através do controle biológico, o uso de produtos fitossanitários ainda tem sido necessário. Portanto, o objetivo deste trabalho foi avaliar o desempenho de diferentes inseticidas no controle da broca da cana-de-açúcar, bem como o efeito sobre a produtividade e o açúcar total recuperável (ATR). O experimento foi conduzido no delineamento experimental de blocos ao acaso, com seis tratamentos e quatro blocos. Os tratamentos foram compostos por cinco inseticidas e um tratamento sem aplicação de inseticida. Para o cálculo do índice de infestação da D. saccharalis foram realizadas amostragens mensais a cada 30 dias, durante 12 meses. Após esse período, foi avaliado e calculado o índice de infestação final da D. saccharalis de cada tratamento. Para comparar a produtividade entre os tratamentos, foram colhidas as quatro linhas centrais de cada parcela. Assim, as amostras foram pesadas para o cálculo da produtividade (TCH) e enviadas ao laboratório para análise do açúcar total recuperável (ATR). O inseticida clorantraniliprole (350) proporcionou um menor índice de infestação da broca da cana, além de maior produtividade, em relação aos demais inseticidas. Não houve diferença significativa do parâmetro de açúcar total recuperável (ATR) entre os tratamentos.(AU)

Pest Control, Biological , Saccharum , Lepidoptera , Agricultural Pests , Efficiency , Insecticides , Insecta
Arq. Inst. Biol ; 87: e0152019, 2020. tab
Article in English | LILACS, VETINDEX | ID: biblio-1130052


Root-knot nematode is one of the most important phytosanitary problems for Conilon coffee, as it reduces productivity and is difficult to handle. We aimed at studying the infectivity and damage caused by M. incognita race 1 in the "Jequitibá Incaper 8122" intermediate maturity coffee variety. The experiment was conducted in a greenhouse, in completely randomized design, with five replicates. The clones composing the variety "Jequitibá Incaper 8122" were inoculated with 2,000 eggs + second-stage juveniles of M. incognita race 1. Uninoculated plants were the control. Evaluations were performed 180 days after inoculation, considering the plant height (H), stem diameter (SD), number of leaves (NOL), leaf area (LA), number of plagiotropic branches (NPB), number of nodes (NN), chlorophyll content (CHLO), shoot dry matter (SDM), root fresh matter (RFM), final population (FNP), and reproduction factor (NRF). The nematode reduced NOL in clones 208 and 209, NRF in clones 201, 203, 207 and 208, NN in clones 203, 207, 208 and 209, CHLO in clones 201, 204, 206, 207 and 209, SDM in clones 201, 203, 204 and 205 and RFM in clones 205 and 207. M. incognita race 1 FNP and NRF were larger in clones 208, 201, 207 and 203. Clone 202 had FNP and NRF equal to zero, being immune to the nematode. Clone 206 presented the lowest NRF value among clones parasitized by M. incognita.(AU)

O nematoide-das-galhas é um dos mais importantes problemas fitossanitários para o cafeeiro conilon, por reduzir a produtividade e ser de difícil manejo. Objetivou-se estudar a infectividade e os danos causados por M. incognita raça 1 na variedade de café conilon de maturação intermediária "Jequitibá Incaper 8122". O experimento foi conduzido em casa de vegetação, em DIC, com cinco repetições. Os clones que compõem a variedade "Jequitibá Incaper 8122" foram inoculados com 2.000 ovos + juvenis de segundo estádio de M. incognita raça 1. Plantas não inoculadas constituíram a testemunha. As avaliações foram realizadas 180 dias após a inoculação, sendo avaliados: altura da planta (ALT), diâmetro do caule (DCA), número de folhas (NFO), área foliar (AFO), número de ramos plagiotrópicos (NRP), número de nós (NN), teor de clorofila (CLO), massa seca da parte aérea (MSA), matéria fresca da raiz (MFR), população final (PFN) e fator de reprodução (FRE). O nematoide reduziu o NFO nos clones 208 e 209, NRP nos clones 201, 203, 207 e 208, NN nos clones 203, 207, 208 e 209, CLO nos clones 201, 204, 206, 207 e 209, MSA nos clones 201, 203, 204 e 205 e MFR nos clones 205 e 207. PFN e FRE de M. incognita raça 1 foram maiores nos clones 208, 201, 207 e 203; o clone 202 teve a PFN e a FRE igual a zero, apresentando-se imune ao nematoide. O clone 206 apresentou o menor valor de FRE entre os clones parasitados por M. incognita.(AU)

Coffee Industry , Coffea , Nematoda , Tylenchoidea , Pest Control , Clone Cells , Microscopy, Electron, Scanning Transmission , Coffee , Agricultural Pests
Arq. Inst. Biol ; 87: e1002018, 2020. ilus
Article in English | LILACS, VETINDEX | ID: biblio-1145890


The demand for food in the world grows year after year due in part to population growth, but also to the improvement of emerging markets. Brazil is one of the largest food producers in the world. In 2017, its cereal, legume and oilseed crops totaled 238.6 million tons, 29.2% more than the year before. Much of the great increase in productivity is due to the incorporation of transgenic seeds, especially cotton, maize and soybean, which possess genes that will increase plant's adaptability to harsh soil and water conditions and, resistance to pests, but also tolerance to herbicides. Virtually, all transgenic soybeans planted in Brazil are resistant to glyphosate, the herbicide initially launched on the market by Monsanto in the 1970s under the trade name Roundup. Due to the existence of several transgenic crops tolerant to glyphosate, such as soy, wheat, corn and canola, this product is the most commercialized herbicide in the world. The use of glyphosate allows the sowing of transgenic crops immediately after application, making the planting and maintenance processes very practical. Soybeans, such as other transgenics, have biological safety already well defined, but the use of glyphosate is still an extremely controversial subject. This review presents some historical aspects of the binomial Roundup Ready soybean/glyphosate and discusses the most recent controversies about the use of glyphosate in Brazil and worldwide.(AU)

A demanda por alimentos no mundo cresce ano após ano devido em parte pelo aumento populacional, mas também pela melhoria dos mercados emergentes. O Brasil é um dos maiores produtores de alimentos do mundo. Em 2017, a safra nacional de cereais, leguminosas e oleaginosas totalizou 238,6 milhões de toneladas, 29,2% superior à obtida em 2016. Boa parte do grande aumento da produtividade se dá pela incorporação de sementes transgênicas, especialmente de algodão, milho e soja, que apresentam genes que conferem maior adaptabilidade da planta ao solo, pragas, condições hídricas, mas também conferem resistência a herbicidas. Praticamente toda a soja transgênica plantada no país é resistente ao glifosato, inicialmente lançado no mercado pela empresa Monsanto nos anos 1970 pelo nome comercial Roundup, que é hoje o herbicida mais utilizado no mundo, principalmente pela disseminação da soja e outros produtos transgênicos como trigo, milho e canola. A utilização do glifosato permite a semeadura de culturas transgênicas imediatamente após a aplicação, tornando o processo de plantio muito prático. A soja, como outros transgênicos, apresenta segurança biológica já definida, mas a utilização do glifosato ainda é um assunto extremamente controverso. Esta revisão apresenta alguns aspectos históricos do binômio soja transgênica Roundup Ready/glifosato e discute as controvérsias mais recentes sobre o uso do glifosato no Brasil e no mundo.(AU)

Biotechnology , Food , Genetics , Seeds , Soybeans , Triticum , Agricultural Cultivation , Pest Control, Biological , Population Growth , Agricultural Pests , Containment of Biohazards , Zea mays , Brassica napus , Agribusiness , Herbicide Resistance , Fabaceae
Arq. Inst. Biol ; 87: e0692019, 2020. ilus
Article in English | LILACS, VETINDEX | ID: biblio-1145886


Four deutonymphs of bulb mites (hypopus) from Rhizoglyphus echinopus (Fumouze & Robin) (Acari: Acaridae) were found attached to the head of Atta sexdens in Rio de Janeiro, Brazil. This mite species is commonly associated with ornamental plants and trees with bulbs, corms and tubers. The results of this study provided an insight into the phoretic relationship between mites and ants, indicating the role of the latter in the dispersion of the first. Despite the abundant and diverse mite fauna existing in ants, little is known about their diversity, biology, ecology and the nature of their associations.(AU)

Quatro deutoninfas de ácaros do bulbo (hipopus) da espécie Rhizoglyphus echinopus (Fumouze & Robin) (Acari: Acaridae) foram encontradas fixadas na cabeça de formigas da espécie Atta sexdens no Rio de Janeiro, Brasil. Essa espécie de ácaro está comumente associada a plantas ornamentais e plantas com bulbos e tubérculos. Os resultados desse estudo fornecem uma visão sobre a relação forética entre ácaros e formigas, indicando o papel destas últimas na dispersão dos primeiros. Apesar da abundância e da fauna diversa do ácaro em formigas, pouco se sabe sobre a diversidade, a biologia, a ecologia e a natureza dessa associação.(AU)

Ants , Medulla Oblongata , Mites , Arthropods , Agricultural Pests , Acaridae , Plant Tubers , Insecta
Arq. Inst. Biol ; 87: e0472019, 2020. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1145883


Fusarium wilt, caused by Fusarium oxysporum f. sp. lycopersici, is one of the most important diseases of tomato crop in Brazil. Several alternatives to fungicides have been evaluated in search for products that control this disease and have low environmental impact and toxicity to living beings. In this context, the use of Trichoderma spp. is an alternative to agrochemicals, since they are bioregulators and antagonists of several phytopathogens. This work aimed to evaluate the antagonistic and mycoparasitory action of the Trichodermil 1306 biofungicide against F. oxysporum, and its action in the control of fusarium wilt in tomato seeds and seedlings. The biofungicide was used at concentrations of 0, 50, 100, and 150% of the dose recommended for application of 20 L with a backpack sprayer. The experiment was conducted in a completely randomized design with five replications. Data were submitted to analysis of variance and mean compared by Tukey's test at 5% probability. The 100% Trichodermil concentration was the most efficient for treating tomato seeds. Although this concentration did not show differences in relation to the lowest dose used (50%) in the tomato seed antagonism, mycoparasitism and F. oxysporum incidence tests were recommended because that the lowest concentration resulted in 18% lower root protrusion than that observed with 100% dosage. The in vitro antagonistic and mycoparasitory action of this biological fungicide indicates its potential in the control of fusarium wilt in tomato crops.(AU)

A murcha-de-fusário, causada por Fusarium oxysporum f. sp. lycopersici, é uma das mais importantes doenças da cultura do tomate no Brasil. Várias alternativas aos fungicidas têm sido avaliadas na busca de produtos que controlem a doença e tenham baixo impacto ambiental e toxicidade aos seres vivos. Nesse contexto, o uso de Trichoderma spp. é uma alternativa a agrotóxicos, pois são biorreguladores e antagonistas de vários fitopatógenos. O objetivo do trabalho foi avaliar a ação antagonista e micoparasitória do biofungicida Trichodermil 1306 em F. oxysporum, e no controle da murcha-de-fusário em sementes e mudas de tomate. O biofungicida foi utilizado nas concentrações de 0, 50, 100 e 150% da dose recomendada para aplicação com pulverizador costal de 20 L. O experimento foi conduzido em delineamento inteiramente casualizado, com cinco repetições. Os dados foram submetidos à análise de variância e as médias foram comparadas pelo teste de Tukey a 5% de probabilidade. A concentração de Trichodermil 100% foi a mais eficaz para o tratamento de sementes de tomateiro. Embora essa concentração não tenha se diferenciado da menor dosagem utilizada (50%) para os testes de antagonismo, micoparasitismo e incidência de F. oxysporum em mudas de tomate, sua recomendação se justifica pelo fato da menor concentração ter propiciado protrusão radicular 18% menor do que a observada na concentração de 100%. A ação antagonista e micoparasitória in vitro do fungicida biológico testado no presente estudo indica potencialidade de uso para o controle de murcha-de-fusário em tomateiro.(AU)

Trichoderma , Pest Control , Lycopersicon esculentum , Fusarium/pathogenicity , Seeds , In Vitro Techniques , Agrochemicals , Agricultural Pests , Environment , Environmental Pollution , Toxicity , Fungicides, Industrial/toxicity , Mycoses
Arq. Inst. Biol ; 87: e0842019, 2020. ilus
Article in English | LILACS, VETINDEX | ID: biblio-1130142


Ahasverus advena (Coleoptera: Silvanidae) is a secondary pest of stored grains. It is a polyphagic and cosmopolitan species, with little information about its occurrence in the northern region of Brazil. This study was conducted to report the first occurrence of A. advena in corn grains in the city of Plácido de Castro, in the state of Acre, Brazil. In June 2019, the presence of A. advena under development was observed in a mass of corn grains. The identification was made at the species level using the available dichotomous keys. Since this is the first record of A. advena in corn grains in the city of Plácido de Castro, monitoring insects in the mass of corn grains is necessary to prevent the economic damages caused by A. advena to grains.(AU)

Ahasverus advena (Coleoptera: Silvanidae) é uma praga secundária de grãos armazenados. É uma espécie polifágica e cosmopolita, com poucas informações sobre sua ocorrência na região norte do Brasil. Este estudo tem o objetivo de relatar a primeira ocorrência de A. advena em grãos de milho na cidade de Plácido de Castro, Acre, Brasil. Em junho de 2019, observou-se a presença de A. advena desenvolvendo em uma massa de grãos de milho. A identificação foi feita a nível de espécie com a utilização das chaves dicotômicas disponíveis. Como este é o primeiro registro de A. advena em grãos de milho na cidade de Plácido de Castro, o monitoramento dos insetos na massa de grãos de milho é necessário para evitar danos econômicos causados por A. advena nos grãos.(AU)

Animals , Coleoptera , Edible Grain , Zea mays , Agricultural Pests , Food Storage