The effect of pod scarification by soil inhabiting insects on the quality of groundnuts (Arachis hypogaea L.)

Abstract

The effect of pod scarification by soil insects on the yield and quality of groundnuts was determined at thirty localities in the Highveld Region of South Africa. Subsamples of superficially damaged pods and sound pods were shelled separately, the kernels graded and the different defects noted. Damaged pods yielded significantly more defective kernels (40.07%) than the sound pods (15.93%). The defects could be divided into four categories, viz. ablactated, fungus-infected, prematurely germinated and UBS (unsound, blemished and soiled). UBS was the most prominent defect. There was a significant interaction between total defects and localities, which was presumably due to differences in species composition and population levels of the causative insects. Pod shell damage was shown to be detrimental to quality. Due to the relatively low incidence of pod shell damage (c. 12%) and the allowance of 15% defects in the current grading system, pest control to curb only this type of damage will possibly not be cost effective.

Keywords:

• Damage
• Groundnuts
• pods