Potential of Neoseiulus barkeri (Acari: Phytoseiidae) in integration with synthetic and plant origin pesticides against Bemisia tabaci (Aleyrodidae" Homoptera) and Tetranychus urticae (Acari: Tetranychidae)

Abstract

Insects and mite pests are considered as major constraints for getting higher crop yields per unit area. Demands of toxic free food and safer ecosystem compelled the scientists to use Phytoseiids for the control of these sucking pests. The present study was therefore, carried out to determine the potential of local strain Neoseiulus barkeri (Acari: Phytoseiidae) in the Acarology Research Laboratory, Department of Entomology, University of Agriculture, Faisalabad, Pakistan. Predatory potential revealed that it fed efficiently on Tetranychus urticae (Acari: Tetranychidae) and preferred to feed on immature and eggs while the adults were less likely preferred. It was less efficient feeder of white fly, Bemisia tabaci (Aleyrodidae: Homoptera) and exhibited poor life table parameters. It was confirmed that it fed on immatures of white fly than eggs. Different crop pollens and artificial diets were tested and confirmed that cotton pollen was unsuitable for it, because its life cycle was not completed on this pollen. Rose, caster bean and maize pollens were superior diets showed higher growth/longevity, fecundity and values of life table parameters and pepper, alfalfa, citrus, sarsoon and tomato pollens were moderately better while sunflower pollen was poor diet. Artificial diet comprising of 20% (w/w) pupal hemolymph of silkworm was superior while other diet were inferior. For screening safer pesticides bioassay at different dose rates declared that dimethoate was highly hazardous while thiacloprid, chlorfenapyr were moderately harmful, acetamiprid, diafenthiuron, spirotetramate, hexithiazox were slightly harmful and pyriproxyfen, buprofezin, imidacloprid were harmless. Glycine max and Azadirachta indica seed oils were less toxic due to minimum mortality and higher antioxidant activities at minimum tested dose rates while eucalyptus oil was highly toxic. Biofilm inhibition of tested oils indicated low value against Gram negative E. coli and high for Gram positive Bacillus subtilus bacteria. Results advocate opportunity of declaring compatible plant origin pesticides for N. barkeri along with antioxidant properties and safer for humans and non-target organisms. N. barkeri can be used as promising biocontrol agent of T. urticae while comparatively less effective predator of B. tabaci. It can be reared on selective pollens and artificial diets and can be used in integration with safer chemical and plant origin pesticides in IPM module. It is base line study first time done in Pakistan which will be helpful for upcoming researchers. However, further investigations under semi field and field conditions may reveal more comprehensive results.