Octávio Nakano

Efeito do regulador de crescimento lufenuron na reprodução de Diabrotica speciosa (Germar) (Coleoptera: Chrysomelidae)

The effect of lufenuron (Match CE), an insect growth regulator, on the fecundity and egg hatchability of Diabrotica speciosa (Germar) (Coleoptera: Chrysomelidae) was evaluated under controlled conditions. Newly-emerged adults from a stock culture were sexed and transferred to acrylic cages (1 couple/cage). Fifteen couples were fed on lufenuron-treated bean (Phaseolus vulgaris, L.) leaves during 13 d after emergence. Thereafter, they were fed on untreated bean leaves. The same number of couples were fed on untreated bean leaves during all period of observation. Adult fecundity and egg hatchability were evaluated until the 34 d after emergence. The mean number of eggs laid/female (177.5) and the egg hatchability (19.8 %) were lower when insects were fed on lufenuron-treated leaves compared to 375.4 eggs and 68.7 % of hatchability when insects were fed on untreated leaves, respectively. Lufenuron seems to affect the embryonic development of D. speciosa by means of a transovarian action, thus avoiding larval eclosion. Results show the possibility of applying lufenuron to reduce the offspring production of D. speciosa when adults are fed on treated plants.

As pragas das hortaliças: seu controle e o selo verde

Vegetable crops in Brazil cover an area of about 326 thousand hectares. All vegetables require insecticide application, which represents a threat not only to producers due to risks of intoxications, but also to consumers, due to residues in food. This situation has arisen because, in the majority of the instances, there are few alternatives of chemicals for pest control. Biological control is rarely exploited because, in case of short-cycle plants such as most vegetables, there is little time for effective action of predators and parasitoids. Physical measures, on the other hand, are showing a relative arise in importance, with occasional use of light, pheromone, and mostly yellow color traps. However, when outbreaks of exotic or native pests occur, associated with favorable conditions, only chemical control can mitigate the economic losses in the crop. For this reason, and as a result of the increasing public awareness regarding health and the environment, the creation of a green-certificate or quality-certificate, which assures that, if chemicals are used in the development of products, they must be used properly, is a task that must be imposed immediately, with authorities responsible for instructing the process. In the State of Sao Paulo the Secretary of Agriculture began the implementation of a quality-certificate for strawberries produced in the Atibaia county. Other vegetables are now being considered for inclusion in the a green-certificate scheme.

Nova planta hospedeira e novos padrões cromáticos de Pachycoris torridus (Scopoli) (Hemiptera: Scutelleridae) no Brasil

The occurrence of Pachycoris torridus (Scopoli) on Schinus terebinthifolius Raddi (Anacardiaceae), is recorded for the first time. The specimens were collected in Piracicaba, State of Sao Paulo; only four out of 43 adults showed new spots morphs of pronotum and scutellum.

Ensacamento de frutos do tomateiro visando ao controle de pragas e à redução de defensivos

The development of fruits in paper bags aims at the control of pests, reduction of pesticide residues and the management of qualitative aspects. This work evaluates the efficacy of paper bags in combination with deodorant tablets and garlic clove on the control of the pest agents Neoleucinodes elegantalis, Helicoverpa zea and Tuta absoluta on bunches of tomatoes. Five treatments were set up: paper bags carrying deodorant tablets, paper bags with garlic cloves, paper bags containing no repellent, control without repellent and control with the insecticide methamidophos. The results were assessed by the number of caterpillars found on the fruits. Fruits protected in wax-paper bags and fruits exposed directly to methamidophos during application were compared in regard to the maximum tolerable residue. The use of paper bags reduced the number of caterpillars of N. elegantalis and H. zea per fruit. Pesticide residues on fruits without bags were six times higher than the maximum tolerable. Fruits within paper bags presented residue levels three times lower than the maximum. The use of paper bags for protection of tomato fruits did not alter fruit characteristics. Considering the costs, the use of paper bags for tomato cropping requires higher initial investment, but it supplies a differential market with higher prices.

Ocorrência de Pachycoris torridus (Scopoli) (Hemiptera: Scutelleridae) em Acerola (Malpighia glabra L.) no Brasil

Pachycoris torridus (Scopoli) has been recorded on ten species of plants in Brazil, where is a common pest of purging-nut plant (Jatropha curcas). In this work, the occurrence of this bug, sucking fruits of the Barbados cherry plant (Malpighia glabra), is recorded for first time.

Exigências térmicas e estimativa do número de gerações de Bonagota cranaodes (Meyrick) (Lepidoptera: Tortricidae) em regiões produtoras de maçã do Sul do Brasil

The thermal requirements of the apple leafroller Bonagota cranaodes (Meyrick) (Lepidoptera: Tortricidae) were estimated at four constant temperatures (14, 18, 22 e 26oC) in laboratory (70±10% R.H. and 14:10L:D). Artificial diet was fed to the insects. The low threshold temperature and thermal requirement for eggs, larvae, pupae and biological cycle (egg to adult) were 7,2 e 140; 7,1 e 410; 6,4 e 183 e 6,8oC and 745 GD, respectively. It was estimated that this species complete three to four annual generations. In the three regions, one generation occurs during the winter.

Ocorrência de Naupactus curtus Boheman (Coleoptera: Curculionidae) em três plantas de importância econômica no Brasil

Adults of Naupactus curtus Boheman (Coleoptera: Curculionidae) eating leaves of coffee (Coffea arabica L.), Barbados cherry (Malpighia glabra L.) and mulberry (Morus alba L.) are recorded in Brazil. The record was made during the rainy period, from October 2001 to January 2002, in Piracicaba, State of Sao Paulo.

Concentração e tempo de liberação do feromônio sexual sintético de Bonagota cranaodes (Meyrick) (Lepidoptera: Tortricidae) na cultura da macieira

The effect of five dosis of the synthetic sex pheromone of Bonagota (=Phtheochroa) cranaodes (Meyrick) (a 9:1 blend of E,Z 3,5 dodecanyl acetate and Z9 hexadecenyl acetate) and the duration of the synthetic pheromone under field conditions were evaluated in a commercial apple orchard in Vacaria, RS, Brazil. No significant differences were observed among concentrations ranging from 0.25 to 3.0 mg per rubber septum. Delta traps baited with two virgin females were ca. four times more attractive than those baited with the synthetic sex pheromone at the dosis of 3 mg per septum. Rubber septa containing this amount of synthetic sex pheromone remained attractive for 120 days. Comparing number of males captured in traps baited with the synthetic pheromone and males captured in traps with virgin females during seven months, a significant and positive correlation is observed, demonstrating that the seasonal variations in B. cranaodes population density are detected using the synthetic sex pheromone in delta traps.

Ultramorphology of the metapleural gland in three species of Atta (Hymenoptera, Formicidae)

Differences among the metapleural glands of four female castes of Atta bisphaerica Forel, 1908, A. capiguara Goncalves, 1944 and A. sexdens rubropilosa Forel, 1908 were examined by scanning electron microscope. There were no differences in gland size between the same castes of these species, although the opening gland in A. sexdens rubropilosa had been twice as large as A. bisphaerica. The relative size and functional significance of the metapleural gland among different castes is discussed and similarities between these and the other Formicidae till now studied is presented.

Controle de lagartas dos frutos do tomateiro pelo ensacamento das pencas

The present experiment aimed to reduce the application of insecticides during the cultivation of tomatoes, Lycopersicon esculentum Mill., by protecting the fruits with paper bags. The efficiency of the use of paper bags was evaluated in combination with insect repellents effective against Neoleucinodes elegantalis (Guenee), Helicoverpa zea (Boddie) and Tuta absoluta (Meyrick). Paper bags made of wax paper were chosen, due to their specific characteristics, like resistance, permeability, flexibility, availability in the market and low cost. Two types of repellents were used: deodorant tablets and garlic cloves, which were cut in approximately 90 mm3 pieces. Three assays of the experiment were run, designed in blocks at random. In the first and second assays tomato plants belonged to the commercial variety Santa Clara and in the third to the hybrid Carmen. Five treatments were tested: paper bags containing deodorant tablets, paper bags with garlic cloves, empty paper bags, control without repellent and control with the insecticide metamidophos. Efficiency of the use of wax-paper bags was evaluated by the average number of caterpillars found per treatment. The use of paper bags decreased the number of both species of caterpillars per fruit whether or not associated with repellents. However, the method was not efficient to protect from losses caused by T. absoluta. Therefore, some applications of insecticides will be required for periods of high infestation, even when the fruits are protected inside the bags.The present experiment aimed to reduce the application of insecticides during the cultivation of tomatoes, Lycopersicon esculentum Mill., by protecting the fruits with paper bags. The efficiency of the use of paper bags was evaluated in combination with insect repellents effective against Neoleucinodes elegantalis (Guenee), Helicoverpa zea (Boddie) and Tuta absoluta (Meyrick). Paper bags made of wax paper were chosen, due to their specific characteristics, like resistance, permeability, flexibility, availability in the market and low cost. Two types of repellents were used: deodorant tablets and garlic cloves, which were cut in approximately 90 mm3 pieces. Three assays of the experiment were run, designed in blocks at random. In the first and second assays tomato plants belonged to the commercial variety Santa Clara and in the third to the hybrid Carmen. Five treatments were tested: paper bags containing deodorant tablets, paper bags with garlic cloves, empty paper bags, control without repellent and control with the insecticide metamidophos. Efficiency of the use of wax-paper bags was evaluated by the average number of caterpillars found per treatment. The use of paper bags decreased the number of both species of caterpillars per fruit whether or not associated with repellents. However, the method was not efficient to protect from losses caused by T. absoluta. Therefore, some applications of insecticides will be required for periods of high infestation, even when the fruits are protected inside the bags.