INFLUENCE OP N, P, K, TOTAL SUGAR AND SHOOT MOISTURE CONTENTS ON THE SUSCEPTIBILITY OF SUGARCANE GENOTYPES TO EARLY SHOOT BORER (CHILO INFUSCATELLUS SNELLEN) IN ANDHRA PRADESH

摘要

Studies on effect of nitrogen, phosphorus, potassium and total sugars on the incidence of early shoot borer (ESB), Chilo infuscatellus Snellen (Lepidoptera: Crambidae) in four least susceptible, four moderately susceptible and four highly susceptible sugarcane genotypes in comparison with one susceptible check were carried out at Regional Agricultural Research Station, Anakapalle, Andhra Pradesh, during 2008-10. The analysis of various chemical constituents at 60 days after planting in different sugarcane genotypes showed that low nitrogen (1.247 to 1.313% and 1.307 to 1.413 %) in leaf sheath and shoot tissues and total sugar content (5.34 to 6.38 %) in shoot tissues of least susceptible genotypes (98 A 125, Co 0110, Co 6806 &98A 165) were positively correlated with ESB susceptibility whereas the shoot and leaf sheath tissues of LS genotypes contained high phosphorus (0.413 to 0.48% and 0.311 to 0.324%) and potassium content (2.327 to 2.423% and 1.65 to 2.047%) along with high shoot moisture per cents (80.83 to 88.53 %) which were inversely related to the susceptibility of sugarcane genotypes to ESB and showed negative correlation with varietal susceptibility to ESB.