QUADRATIC REGRESSION ROTATION COMPOSITE DESIGN AND STUDY ON THE EFFECT OF FOUR SPECIES OF SPIDERS ON THE WHITE-BACKED RICE PLANTHOPPER

A mathematical model of the preying of four species of spiders, Oodothorax in-secticeps, Pirata subpiraticus, Clubiona japonicola and Bianar hotingchlechi on the white-backed rice planthopper Sogatella furcifera was studied with quadratic regression rotation composite design and reported in the paper. The mathematical model of the preying of the predators on the white-backed planthopper was asfollows:Y = 13.1492 + 0.4583x1 -0.125x2 + 0.625x3 + 1.0417x4 + 13.9583x5-0.9375x1x2 + 0.4375x1x3 -0.0625x1x4 +2.25x1x5 + 0.1875x2x3 + 0.1875x2x4 - 0.3125x2x5 - 0.6875x3x4 + 0.5625x3x5 + 0.0625x4x6 + 0.1008x12 - 0.2742x22 + 1.2258x32 + 0.1008x42 + 4.4758x52Furthermore, the response surfaces of interaction between two species of spiders were also studied. It proved that there were interference between species and detween individuals of the same species of the four predators.