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URI permanente para esta coleçãohttps://locus.ufv.br/handle/123456789/11843
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Item Hormetic responses of a stinkbug predator to sublethal doses of pyrethroid(Bulletin of Environmental Contamination and Toxicology, 2011-09-25) Zanuncio, Jose C.; José E., Serrão,; Ramalho, Francisco de S.; Zanuncio, Teresinha V.; Ribeiro, Rafael C.; Jusselino-Filho, PedroStressors can affect reproduction and longevity by impacting endocrine and immune systems but they may increase life span and stimulate reproduction. The effects of sublethal doses of permethrin topically applied on third instar nymphs of Podisus distinctus (Heteroptera: Pentatomidae) was evaluated. The weight of females survival of nymph and adults, number of eggs and nymphs/females of P. distinctus were higher when exposed to lower doses of permethrin. On the other hand, the exposition to the 0.131, 1.315 and 13.15 ppb showed positive effects on the oviposition periods, number of egg masses and longevity of P. distinctus females.Item Fertility and life expectancy of a predatory stinkbug to sublethal doses of a pyrethroid(Bulletin of Environmental Contamination and Toxicology, 2012-11-07) Zanuncio, Jose C.; Jusselino-Filho, Pedro; Ribeiro, Rafael C.; Castro, Ancideriton A.; Zanuncio, Teresinha V.; Serrão, Jose E.Podisus distinctus (Heteroptera: Pentatomidae) is an important predator used in biological control of eucalypt defoliating caterpillars, exposed the insecticides. Lower doses of permethrin not affect the values of generation time (T), time necessary to double the population in number of individuals (DT) and intrinsic rate of population increase (r m ). Moreover, females of P. distinctus derived from nymphs treated with lower doses of permethrin were more fertile, triggering the effect hormetic in net reproductive rates (Ro). Results showed that low permethrin doses can be used alongside the predatory stinkbug in Integrated Pest Management programs.Item Effect of the insect growth regulator diflubenzuron on the predator Podisus nigrispinus (Heteroptera: Pentatomidae)(Ecotoxicology, 2011-08-21) Castro, Ancidériton A.; Lacerda, Mabio C.; Zanuncio, Teresinha V.; Ramalho, Francisco de S.; Polanczyk, Ricardo A.; Serrão, Jose ́ E.; Zanuncio, Jose ́ C.Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) is a common natural predator of defoliating caterpillars in agricultural and forest systems. Insecticides acting as growth regulators of insect pests can indirectly affect their predators through consumption of contaminated prey. We examined the reproductive performance of P. nigrispinus fed on caterpillars of Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae) reared on soybean leaves exposed to the chitin synthesis inhibitor, diflubenzuron. Caterpillars of A. gemmatalis were fed for 12 h with treated soybean leaves and offered to adults of the predator P. nigrispinus over five consecutive days. The fertility of P. nigrispinus was reduced when feeding on diflubenzuron treated caterpillars, especially at the beginning of the reproductive period, but recovered 3 weeks later. The effects of diflubenzuron ingestion on the life table parameters of P. nigrispinus included an increase in the period taken to double the population size, and reductions in the intrinsic rate of population increase, generation duration, and net reproductive rate. Diflubenzuron therefore had an indirect negative effect on the reproduction and the population dynamics of the non-target predator P. nigrispinus. Clearly, its use in integrated pest management requires further evaluation.