Population Fluctuation of Spiders in Rice Ecosystem in Relation to Pest Density and Weather Parameters

摘要

Population fluctuation of spiders in rice ecosystem of Bangalore and Mandya districts revealed three major peaks viz., April to May, early July and early September to November. Dominant hunting spiders, Pardosa sumatrana Thorell, Pardosa sp, Clubionaludhianensis Tikader colonized the field rapidly and reached peak during 60 to 75 days after transplanting and their population further declined with the age of the crop. Most of the hunting spiders showed a significant positive correlation with brown planthopper during kharif season in all the locations, only a few showed significant positive with green leafhopper and none of the spiders showed any interaction with yellow stemborer. Lower temperature, moist conditions coupled with grassy bunds increased the spider population.