T Pavani, T Umamaheswari and J.C. Sekhar
Green house experiment was conducted during 2010-11 to estimate the critical stages of maize crop due to S.inferens infesta - tion in a susceptible single cross hybrid DHM 117. Five densities of newly hatched larvae viz., 0, 5, 10, 15 and 20 (here after called L 1 , L 2 , L 3 , L 4 and L 5 , respectively) were released into the leaf whorl at four different leaf stages of crop growth viz., 2 leaf (7 days after germination) (DAG), 4 leaf (14 DAG), 6 leaf (21 DAG) and 8 leaf (28 DAG) stages (hereafter called A 1 , A 2 , A 3 and A 4 , respectively). Results clearly indicated that irrespective of the larval density, plant age between 7 and 14 days was found to be more susceptible to pink borer as evidenced by decrease in LIR at 21 and 28 days age. With increase in the larval density there was an increase in the LIR irrespective of the stage of the crop. Based on the present results, it is important to protect the crop at early stages that is from 7 to 14 days to prevent economic damage by the borer.
T Pavani has completed her M.Sc. Ag at College of Agriculture, ANGRAU , Hyderabad. and now she is doing her Phd programme at ICRISAT, Patancheru.