Phenotypic Screening of Rice Genotypes against Gall Midge, Orseolia oryzae (Wood- Mason) in Warangal, Telangana, India

Abstract

The Asian rice gall midge, Orseolia oryzae (Wood-Mason), is a major endemic insect pest in the Warangal region of Telangana, causing substantial yield losses in rice cultivation. The present investigation was carried out during the Kharif season of 2019 at the Regional Agricultural Research Station, Warangal under Professor Jayashankar Telangana Agricultural University, Telangana, India to assess the resistance of 35 rice genotypes against gall midge infestation. Three resistant checks, namely Aganni, Abhaya and W1263, along with the susceptible check TN-1, were included in the study following the standard screening protocol. The genotypes were evaluated based on percentage plant damage (PD) and percentage silver shoot (SS) incidence. The susceptible check TN-1 exhibited severe infestation, recording 90.0% PD and 24.2% SS incidence, thereby confirming the presence of sufficient pest pressure under field conditions. Among the resistant checks, Aganni displayed a highly resistant reaction, whereas W1263 and Abhaya were categorized as moderately resistant and moderately susceptible, respectively, based on silver shoot incidence. Nevertheless, all resistant checks exhibited comparatively high levels of plant damage (50.0–65.0%), suggesting the highly virulent nature of the local gall midge population. Among the evaluated genotypes, only SKL-07-8-720-63-147-182-276 demonstrated a highly resistant reaction against gall midge infestation. Three genotypes, namely JGL 33016, JGL 33138 and SKL-06-02-27-13-54-239-34, exhibited moderately resistant reactions with less than 5.0% silver shoot incidence. However, these entries recorded plant damage ranging from 25.0 to 50.0%. The findings of the present study indicate that the genotype SKL-07-8-720-63-147-182-276 may serve as a valuable source of resistance and could be effectively utilized in rice breeding programmes aimed at developing gall midge-resistant rice cultivars.