Bioactivity of neem nanoformulations on tomato pinworm

The use of insecticide plants is an important tool in the management of insect pests. Aiming to control Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), neem nanoformulations were evaluated. After estimating the LC50 for a commercial neem oil formulation, selection bioassays were performed with 22 nanoformulations. In order to do that, newly emerged caterpillars were fed on leaflets treated with nanoformulation solutions for 10 days. The effect on the development and longevity of the insect was evaluated with the two most promising nanoformulations, aqueous NC40 and powdered NC40 (NC 40 = Poly- -hydroxibutirate nanocapsules). The LC50 for neem oil was estimated in 0.20% or 1.31mgL(-1) of azadiractin. The nanoformulations aqueous NC40 and powdered NC40 affected the insect development.

Efficiency of neem oil nanoformulations to Bemisia tabaci (GENN.) Biotype B (Hemiptera: Aleyrodidae)

The nanotechnology, through encapsulation of active ingredients, has showed an important way to avoid problems with quickly degradation of the pesticide molecules. Thus, neem (Azadirachta indica) oil nanoformulations containing beta-ciclodextrin and poli-epsilon-caprolactone (PCL) were tested as to their control efficiency against eggs and nymphs of Bemisia tabaci (Genn.) biotype B reared in soybean. The Lethal Concentration (LC50) was estimated using a commercial neem oil (Organic Neem (R)) on first-instar nymphs to establish the adequate volume of the nanoformulations per treatment. After that, they were sprayed on eggs and first-instar nymphs in laboratory and greenhouse and on third-instar nymphs in greenhouse. The commercial neem oil and distilled water were used as controls. Egg viability was not affected by any treatment. Among six nanoformulations, only one was efficient against the first-instar nymphs in laboratory conditions. However, its effective period was not increased as expected. In greenhouse, first-instar nymphs were more affected by two nanoformulations which were significantly different of the commercial neem oil - the most effective one. No mortality differences among the formulations in the third-instar test were observed. The nanoformulations were less efficient to control the B. tabaci biotype B nymphs than the commercial neem oil.

Compatibility of Beauveria bassiana commercial isolate with botanical insecticides utilized in organic crops in southern Brazil

Products based on botanical insecticides and entomopathogenic fungi have been widely used in organic farming, especially in southern Brazil. Thus, this study investigated, in vitro, the effect of aqueous extracts and commercial formulations of plants with insecticidal activity on Beauveria bassiana. The treatments comprised the botanical insecticides Neempro (azadiractin +3-tigloylazadirachtol), at the concentrations of 0.25, 0.5, 0.75, and 1.0% (v/v), and DalNeem (neem oil emulsifiable), at 0.5, 1.0, 1.5, and 2.0% (v/v) (both commercial formulations of Azadirachta indica (neem)), and the aqueous extracts, at the concentrations of 2.5, 5.0, 7.5, and 10.0% (w/v), of neem seeds, tobacco powder (Nicotiana tabacum), and catigua leaves (Trichilia clausenii). In potato, dextrose, and agar culture medium, the effects of each product on the mycelial growth and the production and viability of conidia of B. bassiana were estimated. According to the adopted compatibility index, the aqueous extracts of neem seeds and leaves catigua, depending on the concentration used, and the botanical insecticide Neempro, were classified as compatible with the entomopathogen, becoming important alternatives to integrate programmes of integrated pest management, especially in organic farming systems.

Impact of Aqueous Plant Extracts on Trigona spinipes (Hymenoptera: Apidae)

The stingless bees are an important component of the insect biomass in many tropical areas, due to their collection of nectar and pollen. Trigona spinipes is a widely distributed species in South America, and described as a pollinator of many crops that can be used in a commercial pollinating system. The effects of plant extracts on insects are studied because of the demand for organic food and their selectivity to natural enemies. Plant insecticides are reported as a potential agent for the control of insect pests, however little is known about their impact on beneficial insects. This study investigated the survival of Trigona spinipes (Hymenoptera: Apidae, Meliponini) Fabricius, after exposure to the leaf extracts of Azadiracha indica (Meliaceae), Lippia sidoides (Verbenaceae), Sapindus saponaria (Sapindaceae), Anonna squamosa (Anonnaceae) Cymbopogon winterianum (Poaceae), Corimbia citriodora (Myrtaceae), Jatropha curcas (Euphorbiaceae) and Ricinus communis (Euphorbiaceae) and of seeds of Azadiracha indica, Ricinus communis Nordestina and AL Guarany varieties and Jatropha curcas. The extracts that had the greatest influence on the survival of the bees were A. indica at 3% and 7% of concentration, A. squamosa at a concentration of 10% with 68.89% survival and green leaf of R. communis at a concentration of 7%. The results show that although the extracts were effective in controlling pests, they may also affect the pollinator Trigona spinipes.

INHIBITION OF OVIPOSITION BY NEEM EXTRACT: A BEHAVIORAL PERSPECTIVE FOR THE CONTROL OF THE MEDITERRANEAN FRUIT FLY (DIPTERA: TEPHRITIDAE)

The behavioral inhibitory effect of methanol extracts from neem leaves (Azadirachta indica A. Juss) at different concentrations (0, 10,000, 18,000, 32,000 and 56,000 ppm) was evaluated using naive and experienced medflies (Ceratitis capitata (Wied.)) ovipositing on the fruits of grape cv. 'Italia'. The grapes were immersed in the specific treatments and were exposed for 24 h to 3 pairs of female and male medflies, both nave and experienced, in a choice test. At concentrations >= 18,000 ppm, the extract that was applied to the grapes inhibited oviposition. The previous experience with treated grapes did not affect the response of the medflies. This study is the first step toward the application of the behavior control of the medflies as a tool in grape vineyards. The potential for using oviposition inhibitory in behavioral control of C. capitata are discussed.

INSECTICIDAL AND BEHAVIORAL EFFECTS OF SECONDARY METABOLITES FROM MELIACEAE ON BEMISIA TABACI (HEMIPTERA: ALEYRODIDAE)

We studied the effects of crude extracts and fractions of Azadirachta indica, Melia azedarach, Toona ciliata and Trichilia pallida on both egg and nymph mortality and embryonic development of Bemisia tabaci B biotype, using tomato plants grown in a greenhouse. Next, we studied the host selection behavioral effects on the adult whitefly under laboratory conditions. The dichloromethane extracts from all plant species and fractions of the extract from branches of T. pallida (EBTPD) and of the extract from leaves of T. ciliata (ELTCD) in dichloromethane caused mortality of nymphs, but neither affected egg viability. However, the branches of the ethanolic extract of A. indica increased the period of embryonic development of the B. tabaci. In addition, the tomato leaflets treated with the fraction of ELTCD dichloromethane (0.28%) were the least preferred by adults, reducing the number of insects resting on the tomato leaflets. The ELTCD methanol and EBTPD dichloromethane fractions inhibited B. tabaci oviposition. Thus, Meliaceae derivatives can contribute to the reduction of the B. tabaci population. The susceptibility of the B. tabaci to Meliaceae derivatives and the relevant behavioral changes of this pest are discussed.

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.

Oral glands in dipsadine ""goo-eater"" snakes: Morphology and histochemistry of the infralabial glands in Atractus reticulatus, Dipsas indica, and Sibynomorphus mikanii

Although snake infralabial glands are generally constituted of mucous cells, among dipsadines, they are much more developed and predominantly serous in nature, possibly due to the peculiar feeding habits of some species of this group, the ""goo-eaters"", which feed on soft and viscous invertebrates. We compared the morphology and histochemistry of the infralabial glands of three goo-eater species of Southeast Brazil, Atractus reticulatus, Dipsas indica and Sibynomorphus mikanii. In A. reticulatus the glands are formed by mixed acini composed of mucous and seromucous cells and in D. indica, they are composed of mucous tubules and seromucous acini. In S. mikanii the glands are organized in seromucous acini; mucous cells are restricted to the gland anterior region and to the duct lining epithelium. Ultrastructurally, secretory granule electron density varies from low to moderate, depending on their mucous or seromucous nature. The results indicate a large morphological and histochemical variation in the infralabial glands, probably reflecting differences in the secretion chemical composition and in feeding specialization among the three species. The protein content in the secretory cells can be related with the presence of toxins that can be used in chemical prey immobilization or detaching of snails from their shells. (c) 2007 Elsevier Ltd. All rights reserved.

2D-DIGE analysis of mango (Mangifera indica L.) fruit reveals major proteomic changes associated with ripening

A comparative proteomic investigation between the pre-climacteric and climacteric mango fruits (cv. Keitt) was performed to identify protein species with variable abundance during ripening. Proteins were phenol-extracted from fruits, cyanine-dye-labeled, and separated on 2D gels at pH 4-7. Total spot count of about 373 proteins spots was detected in each gel and forty-seven were consistently different between pre-climacteric and climacteric fruits and were subjected to LC-MS/MS analysis. Functional classification revealed that protein species involved in carbon fixation and hormone biosynthesis decreased during ripening, whereas those related to catabolism and the stress-response, including oxidative stress and abiotic and pathogen defense factors, accumulated. In relation to fruit quality, protein species putatively involved in color development and pulp softening were also identified. This study on mango proteomics provides an overview of the biological processes that occur during ripening. (C) 2012 Elsevier B.V. All rights reserved.

Physical-chemical, thermal, and functional properties of achira (Canna indica L.) flour and starch from different geographical origin

Achira (Canna indica L.) is a plant native to the Andes in South America, a starchy source, and its cultivation has expanded to different tropical countries, like Brazil. In order to evaluate the potential of this species, starch and flours with different particle size were obtained from Brazilian achira rhizomes. Proximal analyses, size distribution, SEM, swelling power, solubility, DSC, XRD analysis, and FTIR were performed for characterization of these materials. Flours showed high dietary fiber content (16.532.2% db) and high concentration of starch in the case of the smaller particle size fraction. Significant differences in protein and starch content, swelling power, solubility, and thermal properties were observed between the Brazilian and the Colombian starch. All the studied materials displayed the B-type XRD pattern with relative crystallinity of 20.1% for the flour and between 27.0 and 28.0% for the starches. Results showed that the starch and flour produced from achira rhizomes have great technological potential for use as functional ingredient in the food industry.