Efeitos da fertirrigação sobre a ocorrência e danos de Mahanarva fimbriolata (Stål) (Hemiptera: Cercopidae) em cana-de-açúcar

Brazil stands out as the world's largest producer of sugarcane and its productivity is closely related to the availability of water and nitrogen during its development and also to the incidence of pest insects. Among the species most harmful to the sugarcane in Brazil, Mahanarva fimbriolata stands out, which has seriously endangered the yields. In this context, the present study aimed to evaluate the effect of the nitrogen fertirrigation on the incidence and damage caused by M. fimbriolata in sugarcane. The experiment was composed of five treatments and four replications in a randomized block design (RBD). The treatments were composed of four doses of N-fertilizer and control (0, 50, 100, 150, 200 kg.ha-1) in drip irrigation system. The parameters evaluated were: number of nymphs in the roots, stalk productivity, sugar content, percentage of sugar, total recoverable sugar and the agricultural contribution margin. It was observed that the fertirrigation increases the productivity of stalks and sugar with the increase of nitrogen fertilization by irrigation. The use of 200 kg.ha-1 of N-fertilizer increased the incidence of M. fimbriolata up to the control and economic damage levels. The biggest financial yield was obtained with the dose of 150 kg.ha-1 of N-fertilizer.

Resistência de genótipos de soja a Dichelops melacanthus (Dallas)(HEMIPTERA: PENTATOMIDAE)

Pós-graduação em Agronomia (Proteção de Plantas) - FCA

Estudos de dispersão de lagartas em milho e soja visando ao manejo de pragas no Brasil e EUA

Pós-graduação em Agronomia (Proteção de Plantas) - FCA

Análise do efeito de inseticidas neonicotinóides sobre a orientação e coleta de alimento de operárias de Apis mellifera L., 1758 (Hymenoptera: Apidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação bioquímica e imunohistoquímica dos efeitos subletais do tiametoxam sobre Apis mellifera (Hymenoptera, Apidae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Seletividade de inseticidas ao parasitoide de ovos Trichogramma pretiosum (hymenoptera: trichogrammatidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Interações moleculares das proteínas CRY1 e VIP3 no controle de lepidópteros em cana-de-açúcar

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Arranjo de semeadura da soja sobre o rendimento da cultura e da tecnologia de aplicação de produtos fitossanitários

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Bioatividade de derivados de Annonaceae sobre Helicoverpa armigera (Hübner, 1808) (Lepidoptera: Noctuidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Bioatividade de nanoformulações de nim sobre a traça-do-tomateiro

O uso de plantas inseticidas é uma importante ferramenta para o manejo de insetos-praga. Visando ao controle de Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), nanoformulações de nim foram avaliadas. Após a estimativa de uma CL50 para uma formulação de óleo comercial de nim, bioensaios de seleção foram realizados com 22 nanoformulações. Para isso, lagartas neonatas foram alimentadas sobre folíolos tratados com soluções das nanoformulações durante 10 dias. Com as duas nanoformulações mais promissoras, NC40 aquoso e NC40 pó (NC 40=nanocápsulas de Poli- β-hidroxibutirato), foi avaliado o efeito sobre o desenvolvimento e a longevidade do inseto. A CL50 para o óleo de nim foi estimada em 0,20% ou 1,31mgL-1 de azadiractina. As nanoformulações NC40 aquoso e NC40 pó afetaram o desenvolvimento do inseto.

Purificação, caracterização e atividade bioinseticida de um inibidor de tripsina de sementes de Crotalaria pallida

A proteinaceous trypsin inhibitor was purified from Crotalaria pallida seeds by ammonium sulphate fractionation, affinity chromatography on immobilized Trypsin-Sepharose and TCA precipitation. The trypsin inhibitor, named ITC, had Mr of 32.5 kDa by SDS-PAGE and was composed by two subunits with 27.7 and 5.6 kDa linked by disulphide bridges, a typical characteristic of Kunitz-Inhibitor family. ITC was stable until 50°C, and at 100°C its residual activity was of about 60%. Also, ITC was stable at pHs 2 to 12. The inhibition of trypsin by ITC was non-competitive, with a Ki of 8,8 x 10-7M. ITC inhibits weakly other serine proteinases such as chymotrypsin and elastase. The inhibition of papain (44% of inhibition), a cysteine proteinase was an indicative of the bi-functionality of ITC. In vitro assays against digestive proteinases from several Lepdoptera, Diptera and Coleoptera pests were made. ITC inhibited in 100% digestive enzymes of Ceratitis capitata (fruit fly), Spodoptera frugiperda and Alabama argillacea, the last one being a cotton pest. It also inhibited in 74.4% Callosobruchus maculatus (bean weevil) digestive enzymes, a Coleoptera pest. ITC, when added in artificial diet models, affected weakly the development of C. capitata larvae and it had a WD50 of 2.65% to C. maculatus larvae

Purificação, caracterização e análise da atividade bioinseticida, de um inibidor de tripsina em sementes de catanduva (Piptadenia moniliformis)

One Kunitz-type trypsin inhibitors (PmTI) was purified from Piptadenia moniliformis seeds, a tree of the sub-family Mimosoideae, by TCA precipitation, affinity chromatography on immobilized trypsin-Sepharose, DEAE cellulose (ion exchange) and Superose 12 (molecular exclusion) column FPLC/AKTA. The inhibitor has Mr of 25 kDa by SDS-PAGE and chromatography molecular exclusion. The N-terminal sequence of this inhibitor showed high homology with other family Kunitz inhibitors. This also stable variations in temperature and pH and showed a small decrease in its activity when incubated with DDT in the concentration of 100mM for 120 minutes. The inhibition of trypsin by PmTI was competitive, with Ki of 1.57 x10-11 M. The activity of trypsin was effectively inhibited by percentage of inhibition of 100%, among enzymes tested, was not detected inhibition for the bromelain, was weak inhibitor of pancreatic elastase (3.17% of inhibition) and inhibited by 76.42% elastase of neutrophils, and inhibited in a moderate, chymotrypsin and papain with percentage of inhibition of 42.96% and 23.10% respectively. In vitro assays against digestive proteinases from Lepidoptera, Diptera and Coleoptera pests were carried out. Several degrees of inhibition were found. For Anthonomus grandis and Ceratitis capitata the inhibition was 89.93% and 70.52%, respectively, and the enzymes of Zabrotes subfasciatus and Callosobruchus maculatus were inhibited by 5.96% and 9.41%, respectively, and the enzymes of Plodia. interpunctella and Castnia licus were inhibited by 59.94% and 23.67, respectively. In vivo assays, was observed reduction in the development of larvae in 4rd instar of C. capitata, when PmTI was added to the artificial diet, getting WD50 and LD50 of 0.30% and 0.33%, respectively. These results suggest that this inhibitor could be a strong candidate to plant management programs cross transgenic

Thiamethoxam on the histological characteristics of sugarcane young roots

Thiamethoxam is a systemic insecticide from the neonicotinoid group, nitroguanidin family which affects the nicotinic receptor acetyl choline in the insect membrane, wounding the nervous system and causing the death of the insect. It was used with success in the control of initial pests of several crops. It was considered that thiamethoxam has a bioactivator effect, because in the absence of insects promoted increase in vigor, development and productivity of crops. This work was carried out to verify if thiamethoxam causes histological changes in sugarcane roots. In this work, it was used optical microscopy, images arrest, tissue biometrics and statistical analysis, in young roots of sugarcane RB 83 5486 after the treatments with different thiamethoxam concentrations. It was determined changes in histological structure of tissues 7, 14, 21 and 28 days after the treatments, establishing its effects on root plant anatomy. It was verified that thiamethoxam increased root cortex width, increasing the vascular cylinder and the metaxylem vessel elements number in the vascular tissue until 21 days after application.

Monitoramento preliminar de psilídeos em plantios florestais experimentais e na vegetação nativa no Amazonas.

Este trabalho teve como objetivo monitorar e identificar a biodiversidade de espécies de Psylloidea em plantios florestais experimentais e na vegetação nativa no Campo Experimental da Embrapa Amazônia Ocidental, em Manaus, AM.

Ocorrência de joaninha Azya luteipes 1850 Mulsant (Coleoptera: Coccinellidae), agente de controle biológico de cochonilhas do cafeeiro, em Porto Velho, Rondônia.

Publicação que reúne informações sobre a ocorrência de joaninha Azya luteipes em plantações de café Conilon, no município de Porto Velho, Rondônia.