Assessment of Number of Leafhoppers as Indicator of Resistance of Sesame Genotypes
K. Swathi *
Department of Entomology, Agricultural College, Bapatla, Acharya N.G. Ranga Agricultural University, India and Division of Crop Protection, ICAR-IIOR, Hyderabad-500030, India.
S. R. Koteswara Rao
Department of Entomology, Agricultural College, Bapatla, Acharya N.G. Ranga Agricultural University, India.
T. Boopathi
Division of Crop Protection, ICAR-IIOR, Hyderabad-500030, India.
K. Sakthivel
Division of Crop Protection, ICAR-IIOR, Hyderabad-500030, India.
D. Ramesh
Department of Statistics, Agricultural College, Bapatla, Acharya N.G. Ranga Agricultural University, India.
*Author to whom correspondence should be addressed.
Abstract
Host plant resistance (HPR) is recognised as one of the most cost-effective, environmentally sustainable strategies for managing vector-borne diseases such as phyllody. Leafhoppers, particularly Hishimonus phycitis and Orosius albicinctus, are the principal vectors of sesame phyllody, a phytoplasma-induced disease that severely reduces crop productivity by converting floral structures into vegetative forms. Although several leafhopper species occur on sesame, only a few are efficient vectors of phyllody. The deployment of resistant genotypes is regarded as the most economical and sustainable approach for managing this disease. In the present study, 280 ICAR-IIOR sesame lines, along with a resistant check (GT-10) and a susceptible check (RJR-170), were evaluated under open field conditions during two seasons (2023 and 2024). A combined mean across seasons was also calculated to obtain unbiased results, and germplasm entries were categorised accordingly. Considerable variation in leafhopper populations were observed among the genotypes. Two sesame genotypes, IC 500521 and IC 500520, consistently demonstrated high levels of resistance to leafhopper infestation across both seasons. The resistant genotypes identified in this study could serve as valuable sources for future sesame breeding and integrated pest management programmes.
Keywords: Sesame, Hishimonus phycitis, Orosius albicinctus, phyllody, resistance, screening, field evaluation