Influence of rice varieties and plant nutrients on the incidence of yellow stem borer, Scirpophaga incertulas (Walker) under protected condition

Field experiments conducted during summer, 2003–04 through kharif 2004 to study the incidence of yellow stem borer (YSB) in response to rice varieties and NPK nutrient levels with and without Zn in protected and unprotected conditions revealed that the incidence of YSB was more in kharif than in summer season. The variety Surendra sustained least damage by YSB during both the seasons. The extent of damage by YSB increased with increase in doses of NPK. The nutrient level 60: 30: 30 kg NPK/ha with ZnS0₄ (F₃) recorded minimum borer incidence irrespective of varieties and insecticidal treatment. The insecticide ‘triazophos’ also proved effective in minimizing the dead heart (DH) incidence significantly at nutrient above level F₃. The moderately resistant variety Surendra treated with triazophos could be effectively protected from YSB attack at reproductive stage during kharif, 2004 when the crop was raised under same nutrient level.