Biochemical Factors Influencing Resistance of Black Gram to Callosobruchus maculatus (Coleoptera: Chrysomelidae)

Abstract

Background: Pulses constitute a cornerstone of the Indian diet, renowned for their rich protein content and nutritional benefits, frequently dubbed as the vegetarian’s protein powerhouse. Black gram not only provides nutritional benefits but also improves soil properties and fixes atmospheric nitrogen. If left unattended in storage, damage inflicted by three species of callosobruchus viz., C. chinensis, C. maculatus and C. analis on black gram seeds could result in substantial losses, both in quantity and quality. In the context of insect resistance, a host genotype’s ability to resist insect pests is demonstrated through non-preference, antibiosis, or tolerance, and is closely linked to the morphological, physiological and biochemical traits of the germplasm. The present study aims to pin point the specific biochemical properties of black gram seeds that contribute to their resistance against the pulse beetle. Methods: The experiment was conducted at the Department of Entomology and Agriculture Zoology, Institute of Agricultural Sciences, BHU, Varanasi during 2020-21. Bioassay investigations were undertaken on twelve varieties of black gram, evaluating various parameters including oviposition, adult emergence, mean development period, growth index, susceptibility index, and the biochemical constituents that could potentially impact the proliferation of the pulse beetle population. Result: The results revealed that tannins and phenols played a significant role in providing resistance. In contrast varieties with high sugars and proteins are susceptible to pulse beetle. However, an increase in the level of phenols and tannins in seeds may interfere with consumer acceptance and these aspects can be used in the breeding programme so as to develop host plant resistance against C. maculatus.