Abstract:
Eighteen varieties of paddy were screened for their relative susceptibility to infestation
by Cnaphalocrocismedinalis The cviposition response of the different varieties
varied significantly. The varieties could be ranked in the following ascending order with
reference to the extent of preference: Kochuvithu, TKM6, TKM1, Adt27, Ptb9, Pankaj,
Triveni, 1' 1. Cavery, IR20, Aswathi, Karuna, Jagannath, Annapoorna, Rohini, Mashoori
Jaya and iRH- Based on the extent of leaf damage caused by the larvae, Kochuvithu
ranked as the least susceptible variety followed by TKM6, TKM1, Ptb9, Adt 27, Pankaj,
Triveni, IR20, H4 Cavery, Aswathi, Karuna, Annapoorna and Jagannath there being
no significant difference among themselves. IR8, Jaya, Rohini and Mashoori were most
susceptible. Based on the extent of leaf damage caused by the larvae Kochuvithu ranked
as the least susceptible variety followed by TKM6, TKM1, Ptb9, Adt 27, Pankaj, Triveni.
IR20, H4, Cavery, Aswathi, Karuna, Annapoorna and Jagannath, there be ing no significant
difference among themselves. Susceptibility of the riee varieties to damage by leaf
roller in the field was positively correlated with the number of eggs laid on them.
