ABSTRACT
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.
Subject(s)
Environmental Exposure , Heteroptera/physiology , Insecticides/pharmacology , Permethrin/pharmacology , Animals , Female , Fertility , Life Expectancy , Male , Nymph/physiology , Ovum/physiologyABSTRACT
Stressors 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.
Subject(s)
Dose-Response Relationship, Drug , Heteroptera/drug effects , Hormesis , Insecticides/toxicity , Permethrin/toxicity , Animals , Environmental Exposure , Female , Insect Control , Longevity/drug effects , Nymph/drug effects , Oviposition/drug effects , Ovum/drug effects , Regression Analysis , Stress, Physiological , Toxicity Tests, Subacute/methodsABSTRACT
The oil palm Elaeis guineensis is usually attacked by pests, particularly, defoliating caterpillars. Between 2004 and 2006 a stinkbug predator (Asopinae) was registered preying on caterpillars of Brassolis sophorae L., Opsiphanes invirae Hübner (Lepidoptera: Nymphalidae) and Sibine spp. (Lepidoptera: Limacodidae), reducing their populations in commercial oil palm plantations in the State of Pará, Brazil. Specimens of the natural enemy were collected, mounted, and identified as Alcaeorrhynchus grandis (Dallas) (Hemiptera: Pentatomidae), corresponding to the first report of the occurrence of this stinkbug attacking defoliating caterpillars of oil palm in Brazil.
Subject(s)
Arecaceae/parasitology , Hemiptera/physiology , Lepidoptera/physiology , Lepidoptera/parasitology , Animals , BrazilABSTRACT
The oil palm Elaeis guineensis is usually attacked by pests, particularly, defoliating caterpillars. Between 2004 and 2006 a stinkbug predator (Asopinae) was registered preying on caterpillars of Brassolis sophorae L., Opsiphanes invirae Hübner (Lepidoptera: Nymphalidae) and Sibine spp. (Lepidoptera: Limacodidae), reducing their populations in commercial oil palm plantations in the State of Pará, Brazil. Specimens of the natural enemy were collected, mounted, and identified as Alcaeorrhynchus grandis (Dallas) (Hemiptera: Pentatomidae), corresponding to the first report of the occurrence of this stinkbug attacking defoliating caterpillars of oil palm in Brazil.
