Sheila A. Mourão

Seletividade de extratos de nim (Azadirachta indica A. Juss.) ao ácaro predador Iphiseiodes zuluagai (Denmark & Muma) (Acari: Phytoseiidae)

The relative toxicity of the leaf, seed and oil neem cake extracts of Azadirachta indica A. Juss (neem) to the predatory mite Iphiseiodes zuluagai (Denmark & Muma) (Acari: Phytoseiidae) was evaluated. To verify the relative toxicity of these extracts on the predatory mite, discriminating concentrations of the extracts were determined for adult females of the Oligonychus ilicis (McGregor) (Acari: Tetranychidae), through the method of concentration-mortality. Coffee leaf disks with 3.5 cm of the diameter were put floating on water and impregnated with dry residue of the extracts. Concentrations of neem extracts which caused mortality (99%) of O. ilicis, after 72h of exposition, were 277.4; 520.9 e 10.9 mg/ml for leaf, seed and oil neem cake, respectively. The discriminating concentration of extract of oil neem cake for O. ilicis females was highly toxic to I. zuluagai; while extract of leaf and seed were selective to the predatory mite.

Toxic effects of the neem oil (Azadirachta indica) formulation on the stink bug predator, Podisus nigrispinus (Heteroptera: Pentatomidae).

This research investigated the effects of neem oil on mortality, survival and malformations of the non-target stink bug predator, Podisus nigrispinus. Neurotoxic and growth inhibitor insecticides were used to compare the lethal and sublethal effects from neem oil on this predator. Six concentrations of neem oil were topically applied onto nymphs and adults of this predator. The mortality rates of third, fourth, and fifth instar nymphs increased with increasing neem oil concentrations, suggesting low toxicity to P. nigrispinus nymphs. Mortality of adults was low, but with sublethal effects of neem products on this predator. The developmental rate of P. nigrispinus decreased with increasing neem oil concentrations. Longevity of fourth instar nymphs varied from 3.74 to 3.05 d, fifth instar from 5.94 to 4.07 d and adult from 16.5 and 15.7 d with 0.5 and 50% neem doses. Podisus nigrispinus presented malformations and increase with neem oil concentrations. The main malformations occur in wings, scutellum and legs of this predator. The neem oil at high and sub lethal doses cause mortality, inhibits growth and survival and results in anomalies on wings and legs of the non-traget predator P. nigrispinus indicating that its use associated with biological control should be carefully evaluated.

Herbivoria de Tetranychus urticae Koch (Acari: Tetranychidae) induz defesa direta em morangueiro?

Plants of strawberry Fragaria x ananassa may present mechanisms of direct and indirect defenses against herbivores. Such defenses may influence behaviour and development of phythophagous mites and their natural enemies, thereby reducing herbivory rate. We tested the effect of pre-infestation of strawberry plants by Tetranychus urticae Koch on the development and reproduction of the mite species. Strawberry plants (cultivar IAC Campinas) were divided into two groups: plants without and plants with pre-infestation of T. urticae. The length of immature phases, the number of eggs per female and the survival of mites were not altered by the pre-infestation. These results may be associated to either the absence or low level of induced resistance of the cultivar IAC Campinas or perhaps the pre-infestation was insufficient to induce defenses. The reported resistance of this cultivar to T. urticae could be related to indirect defenses.

Efeito da escassez de presa na sobrevivência e reprodução do predador Supputius cincticeps (Stål) (Heteroptera: Pentatomidae)

The effect of prey shortage on the performance of Supputius cincticeps (Stal) females was evaluated at 24.6 ± 0.7oC, 80 ± 4% RH and 12h photophase. Larvae of Tenebrio molitor L. were offered to the females during 24h every one, two, four, six or eight days; pieces of green bean (Phaseolus vulgaris L.) were offered continuously. The percentage of females with egg masses, oviposition period, and the number of egg masses, eggs and nymphs decreased with the increase in the interval without prey, whereas the periods of pre- and pos-oviposition increased. On the other hand, longevity and number of eggs per egg mass were not affected by the prey regimen. The results suggest a trade-off between longevity and fecundity (reduction of fecundity to maintain longevity), which could contribute to the establishment and survival of S. cincticeps during periods of prey scarcity.

Mortality of Anticarsia gemmatalis (Lepidoptera: Noctuidae) Caterpillars Post Exposure to a Commercial Neem (Azadirachta indica, Meliaceae) Oil Formulation

Abstract The velvetbean caterpillar, Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae), is the most important defoliator of soybean (Glycine max L. Merrill, Fabaceae) crops in Brazil. Early-instar caterpillars of this pest are the main target of control. The objective of this work was to evaluate the toxicity of a commercial product, Bioneem® [neem oil (Azadirachta indica A. Juss., Meliaceae)], sprayed on A. gemmatalis caterpillars. Bioneem® was sprayed on soybean plants and 3 h later specific branches were enclosed by organza bags in a greenhouse with third-instar A. gemmatalis caterpillars. Ten replications with 80 caterpillars were used per treatment. The mortalities of A. gemmatalis caterpillars (mean 3rd to 6th instars) was 3.17, 7.18, 5.00, 11.25, 16.74, and 18.15%, whereas the respective mortalities of the pupae obtained from treated the caterpillars were 20.57, 22.79, 29.64, 39.16, 51.50, and 59.17%. The viabilities until the pre-pupal stage were 76.26, 70.03, 65.36, 49.59, 31.76, and 22.68% with 2.5, 5, 10, 15, 20, and 25% of the neem oil, respectively. The larval stage of this pest (3rd instar to pre-pupa) lasted longer in the 20% neem oil treatment than at the other rates, but its longevity was not affected. Anticarsia gemmatalis pupae presented developmental interruptions and anomalies at all concentrations of neem oil. The commercial product Bioneem® (neem oil) can therefore be used as a suitable alternative to synthetic insecticides to control A. gemmatalis.

Toxicidade de extratos de nim (Azadirachta indica) ao ácaro-vermelho-do-cafeeiro Oligonychus ilicis

The objective of this work was to study the toxicity of extracts of oil cake, seeds and leaves of Azadirachta indica A. Juss (neem) to the coffee red mite Oligonychus ilicis (McGregor) (Acari: Tetranychidae). Concentration-mortality and instantaneous rate of populational growth were determined for adult females of the red mite on disks of coffee with 3.5 cm diameter, floating on water and impregnated with dry residues of the neem extracts. Concentrations of these extracts which caused 50% mortality of the individuals of O. ilicis were 0.02, 15.9 and 121.4 mg/mL; while 99% mortality of this mite was reached with 10.9, 520.9 and 277.4 mg/mL for oil cake, seeds and leaves extracts, respectively. The instantaneous rate of populational growth of O. ilicis dropped as the extract doses increased up to 0.075, 15 and 144 mg/mL for oil cake, seeds and leaves extracts, respectively.

Seletividade de defensivos agrícolas ao fungo entomopatogênico Beauveria bassiana

The relative toxicity of the insecticides organophosphates methyl-chlorpyrifos, disulfoton, ethion, methyl-parathion, the organochlorinate endosulfan and the mixture of the fungicide triadimenol and the insecticide disulfoton and the sterol demethylation inhibiter fungicide (triadimenol and tebuconazole) to the fungus Beauveria bassiana (Balsamo) Vuillemin was evaluated. Concentrations which inhibited radial mycelium growth (99%) of B. bassiana were 0.42; 1.69; 6.53; 14.42; 31.75; 7,028.96; 10,326.76 e 763,959.86 mg i.a/ml of tebuconazole, methyl-parathion, triadimenol, triadimenol + disulfoton, methyl-chlorpyrifos, ethion, endosulfan and disulfoton, respectively. The effects of these products were evaluated based on percentage of inhibition of radial mycelium growth of B. bassiana on potato dextrose-agar impregnated with them, after seven days. Tebuconazole, methyl-parathion and methyl-chlorpyrifos were highly toxic to B. bassiana; endosulfan and triadimenol + disulfoton were moderated toxic; while triadimenol, ethion, and disulfoton were selective to this fungi.

Apate terebrans (Pallas) (Coleoptera: Bostrychidae) atacando árvores de nim no Brasil

This paper describes and records the attack of adults Apate terebrans (Pallas) to a neem plantation located in Guarani, State of Minas Gerais, Brazil, in March 2007. The damage was characterized by a hole in the trunk, from where the shot-hole-borer enters constructing tunnels and feeding on the wood. This is the first record of A. terebrans attacking neem trees in Brazil.

PROVISION OF THE DIAGNOSIS OF SOLID WASTE CONSTRUCTION IN THE CITY OF MONTES CLAROS, MG

The expansion of the construction sector in the city of Montes Claros (MG) has been causing a significant increase in the generation of solid waste, which are often deposited in irregular locations. But actions have been taken to reverse these environmental impacts, including the enactment of local laws that establish guidelines, criteria, procedures for the management of waste from construction and demolition and determine responsibilities between the generators, carriers and municipal agencies. This study aimed to estimate the generation and map the main irregular disposal sites of waste from construction and demolition in Montes Claros. Therefore, the survey was conducted in two stages, first visited to state and local public agencies and agents involved in generating and collecting debris in Montes Claros, and thus sought to information needed to estimate the generation of the waste from construction and demolition. Already, the mapping of the waste from construction and demolition disposal sites was through on-site photographic surveys in regional centers determined by the Municipality of the city. Through research it was possible to understand the agent involved in the generation, treatment and disposal of solid waste related to construction in the city of Montes Claros. That it was detected irregular provisions in dissimilar parts of the city. Apparel promoting the degradation of the various environments involved directly and indirectly to these materials; and that the deployment of relation to waste management programs for construction is the guiding factor for the reduction in the volume of these materials in the city.