Mortality data were subjected to appropriate transformation prior analysis. LT50
values and associated statistics were estimated by subjecting mortality data to the
maximum likelihood program of probit analysis Robertson et al. (2007) using SPSS
(1999) software. The values and significance of χ2 and the 95% CI for potency ratios
were determined (Norǘsis, 2008). Parallel regression lines were also compared using
overlapping confidence limits (P ≤ 0.05) of relative potencies as the criterion to detect
significant differences in mortality. Analysis of variance was used to check the
significance of differences between mortality of insects at different cold storage and
radiation exposure time, and also differences in the mortality of different insect
species. In seed viability tests, the data were normalized by using arcsine-square-root
transformation; the data then were analyzed using one-way analysis of variance
(ANOVA) followed by Tukey’s honestly significant difference test to determine
statistical differences between means at P ≤ 0.05. Student’s t-test was used for
comparing the means of two independent groups.