predation rate is basic to any investigation of prey-predator interaction and a major component in the selection of predators for biological control. the predation rate of variegated lady beetle, hippodamia variegata (goze), fed on different densities (20, 40, 60, 80 and 100) of third instar nymphs of cotton aphid, aphis gossypii glover, was studied under laboratory conditions (25 ± 1 °c, 65 ± ...

BACKGROUND Pesticide resistance monitoring is a crucial part to achieving sustainable integrated pest management (IPM) in agricultural production systems. Monitoring of resistance in arthropod populations is initially performed by bioassay, a method that detects a phenotypic response to pesticides. Molecular diagnostic assays, offering speed and cost improvements, can be developed when the caus...

Host specialization is a ubiquitous character of phytophagous insects. The polyphagous population is usually composed of some subpopulations that can use only a few closely related plants. Cotton-melon aphids, Aphis gossypii Glover exhibited strong host specialization, and the cotton- and cucurbits-specialized biotypes had been clearly identified. However, the experimental work that addressed t...

A tractor-operated automatic gun sprayer was developed for the cotton crop. The unit consists of frame structure, spray tank, horizontal triplex pump, control valves, nozzle, pressure gauge, strainer, hydraulic agitator and actuating mechanism. power to drive HTP pump taken from tractor take off (PTO) through a belt pulley. mechanism motor worm gear reduction. Two motors with 0.5 kW each (12 V ...