Stage preference and functional response of Rhynocoris longifrons (Stal) (Hemiptera: Reduviidae) on three hemipteran cotton pests.

摘要

In this work, the stage preference and functional response of the indigenous reduviid bug Rhynocoris longifrons feeding on five different densities of the cotton aphid Aphis gossypii, Phenacoccus solenopsis, and Dysdercus cingulatus was examined in Petri dish arenas containing cotton leaves under laboratory conditions. The reduviid predator exhibited a Type II functional response at all hemipteran pests evaluated when data were fit to Holling's disc equation. Predatory rate gradually increased while the predator grew older and adults consumed maximum number of D. cingulatus and P. solenopsis. An opposite trend was observed, while the reduviid was provided with Aphis gossypii. The rate of attack on P. solenopsis was quite low but fairly consistent, with the different life stages of the predator generally more effective. Further investigation of the biological control potential of R. longifrons against cotton pests under pot and controlled filed should be done due to the predator's ability to kill adult stages of all prey species evaluated. These results indicated that R. longifrons could eat more aphids at high prey densities; however, predators also considerably reduced other cotton pests too so it could be considered a prospective candidate for use as a commercial biological control agent for cotton hemipteran pests in India.