Influence of rice grain traits to their susceptibility to the lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera, Bostrichidae)

Abstract

Rice grains of 20 varieties were tested for their physical and biochemical basis of resistance against lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera, Bostrichidae). Physical parameters such as grain length x breadth, thousand seed weight, and grain hardness exhibited significant differences among tested varieties. Grain hardness conferred resistance significantly by resulting in delayed adult emergence (-0.519), and weight loss per cent (-0.603). Biochemical parameters such as total carbohydrates and proteins showed significant differences among the varieties. Total carbohydrate was positive and significantly correlated with adult emergence, but with median development period negatively correlated. Protein content was also found positively correlated with adult emergence and negatively correlated with the median development period.