Evaluation of biophysical, anatomical and biochemical traits of resistance to Sitophilus oryzae L (Coleoptera: Curculionidae) in stored maize

Sitophilus oryzae L is the most destructive insect pest of stored maize and is widely distributed in tropical regions. In the present study, eighteen maize genotypes were screened for several susceptibility parameters against S. oryzae by using «No Choice method». Biophysical traits (test weight, thousand kernel weight, kernel hardness), anatomical fractions (tip cap, germ, pericarp, endosperm), biochemical variants (starch, protein, oil, sugar) were correlated with insect susceptibility parameters. There is significant relationship among test weight, kernel hard- ness, and insect susceptibility parameters. Pericarp was positively correlated while endosperm, starch content were negatively correlated with median development period but were non-significant. Majority of the maize geno- types containing harder kernels and thick pericarp showed less susceptibility to S. oryzae. The results indicated that the biophysical, anatomical and biochemical traits are responsible for varying levels of resistance to S. oryzae