Screening of different soybean genotypes for resistance to whitefly (Bemisia tabaci) infestation

Abstract

Whitefly (Bemisia tabaci Genn.) is one of the major sucking pests of soybean causing significant yield losses through sap feeding and transmission of viral diseases. Identification of resistant genotypes is an important component of sustainable pest management. The present study was conducted to evaluate soybean genotypes for resistance against whitefly incidence during the Kharif seasons of 2023–24 and 2024–25 under natural field infestation conditions. Twenty soybean genotypes were screened and observations on whitefly population were recorded at weekly intervals starting from 15 days after sowing (DAS). The whitefly population was assessed on the basis of number of whiteflies per six leaves per plant, and the mean population for each genotype was calculated by averaging weekly observations. Based on mean whitefly population, the genotypes were categorized into different resistance groups. During Kharif 2023–24, the mean whitefly population ranged from 3.02 to 7.71 whiteflies per six leaves. The lowest population was recorded in genotype JS 97-52 (3.02), followed by AMS-100-39 (3.47), NRC-138 (3.65) and JS 20-98 (3.81), whereas the highest population was observed in JS-335 (7.71). Similar trends were observed during Kharif 2024–25, where mean whitefly population varied from 2.82 to 7.41 whiteflies per six leaves. Genotype JS-97-52 recorded the lowest population (2.82), followed by AMS-100-39 (3.21), NRC-138 (3.35) and JS-20-98 (3.55), while JS-335 showed the highest infestation (7.41). Pooled analysis of two years revealed that the mean whitefly population ranged from 2.92 to 7.56 whiteflies per six leaves. Genotypes JS 97-52 and AMS-100-39 were categorized as highly resistant, NRC-138 and JS 20-98 as resistant, several genotypes as moderately resistant, while JS-20-116 and JS-335 were found to be susceptible and highly susceptible, respectively. The identified resistant genotypes may serve as potential sources for developing whitefly-resistant soybean cultivars.