Department of Plant Protection, University of Mohaghegh Ardabili, Ardabil, Iran.
In this study, the spatial distribution of overwintered adults of Sunn pest, Eurygaster integriceps Puton, was investigated by using dispersion parameters and indices, mathematical distribution, and regression techniques in rainfed wheat fields by sample size of 1 m2 in 2009 and 2010. The dispersion parameters including: mean-variance test and clumping parameter () showed that the overwintered adults of Sunn pest population followed the negative binomial distribution pattern. Furthermore, the dispersion indices including: variance to mean ratio, Lloyd's index of mean crowding and Morisita index also confirmed the aggregated distribution pattern of overwintered adults of Sunn pest. Also, mathematical distribution and Taylor's power law () and Iwao's patchiness regression () showed the contagious distribution of overwintered adults of E. integriceps. These results can be useful in patch spraying for control of overwintered adults of E. integriceps in early season in wheat fields.