Assessment of Rice Gall Midge, Orseolia oryzae (Wood Mason) Biotype Using Gene Differentials in Rudrur, Nizamabad District, Telangana State, India
Saicharan M *
Regional Sugarcane and Rice Research Station, Rudrur, Nizamabad, Telangana, India.
S. Omprakash
Regional Agricultural Research Station, Warangal, Telangana, India.
A. Krishna Chaitanya
Regional Sugarcane and Rice Research Station, Rudrur, Nizamabad, Telangana, India.
Ramya Rathod
Regional Sugarcane and Rice Research Station, Rudrur, Nizamabad, Telangana, India.
B. Soundharya
Regional Agricultural Research Station, Warangal, Telangana, India.
Y. Samatha Parameswari
Regional Sugarcane and Rice Research Station, Rudrur, Nizamabad, Telangana, India.
T. Anjaiah
AICRP on Weed Management, PJTAU, Hyderabad, Telangana, India.
B. Balaji Naik
Centre for Digital Agriculture and Technology, PJTAU, Hyderabad, Telangana, India.
*Author to whom correspondence should be addressed.
Abstract
The rice gall midge (Orseolia oryzae) remains a major constraint to rice production in Telangana, where recent outbreaks have raised concerns about shifts in virulence and the possible emergence of new biotypes. To generate reliable, locality-specific information for resistance deployment, a structured biotype characterization study was carried out for three consecutive kharif seasons (2023–2025) at the Regional Sugarcane and Rice Research Station (RS&RRS), Rudrur. Twenty standard rice gall-midge differential lines of 5 groups, representing Gm1-Gm11 resistance sources and unknown sources were evaluated under natural field infestation using established biotype identification protocols. Consistent reactions were recorded across seasons, with all Group II differentials (Gm2 - Gm10) showing uniform susceptibility, while differentials carrying Gm1, Gm3, Gm4, Gm8, and Gm11 expressed stable resistance. The susceptible check TN1 exhibited high silver-shoot incidence each year, confirming adequate pest pressure. The cumulative resistance susceptibility pattern observed across Groups I-V corresponded closely with the diagnostic profile of Biotype 3. These findings provide the first comprehensive evidence on the prevailing gall-midge biotype in the Rudrur region of Northern Telangana and offer a robust foundation for selecting suitable resistant varieties and designing sustainable pest-management strategies for the state’s rice ecosystems.
Keywords: Gene Differentials, biotype, rice, gall midge, kharif seasons