Cotton genotype and plant age effects on the preying capacity of Orius insidiosus on Aphis gossypii

Abstract

The predatory capacity of Orius insidiosus (Say, 832) (Hemiptera: Anthocoridae) female on third/fourth instar of Aphis gossypii Glover, 877 (Hemiptra: Aphididae) was evaluated in cotton plants of different ages (20, 30, and 40 day old) and cultivars (Antares, CNPA7H e Acala 90 - respectively, without tricome, with medium tricome density and high tricome density). Cotton plants were individualized and infested with 5 aphids followed by the release of one female of the predator per plant. No difference in preying rates were found as influenced by plant age and leaf size. A. gossypii was predated at different rates in the smallest (Acala 90) and the largest (CNPA7H) leaf size, varying from 4.94±.55 to 3.8±.76 aphids/nymphs and adults. These results show that O. insidiosus predatory capacity was not modified by leaf size and plant age up to 40 day old cotton plants. Additional keywords: Biological control, minute pirate bug, Gossypium hirsutum, cotton aphid.