Alternative IPM strategy against rice leaf folder Cnaphalocrocis medinalis Suri K. S.1,*, Makkar Gurpreet Singh2 1Department of Entomology, Punjab Agricultural University, Ludhiana, 141004 2Department of Plant Breeding and Genetics, Punjab Agricultural University, Ludhiana, 141004 *Corresponding author Email: kssuri@pau.edu
Online published on 5 February, 2019. Abstract The present study evaluated the mechanical control method in combination with chemical control as an alternative IPM strategy against rice leaf folder (RLF), Cnaphalocrocis medinalis in a series of 11 multilocation trials. Passing of the coir and jute ropes, forwards and then backwards, both ways while touching the crop canopy, before flowering stage of rice, proved significantly better (with 71.07 and 69.56% opening of folded leaves, respectively) than that of the nylon rope (with 54.45% opening of folded leaves) in mechanical dislodging of larvae. The 20 m length of coir/jute rope proved marginally superior (69.94% opened leaves) over the 30 m rope length (67.61% opened leaves) in mechanical opening of infested leaves, but both were significantly better than the 40 m rope length (52.06% opened leaves). Among the two strategies evaluated-T1 (mechanical control during pre-flowering stage + insecticide spray during post-flowering stage) gave yield of 33.2 and 75.5 q/ha in basmati and non-basmati, respectively; and T2 (two insecticide sprays, one each during pre-flowering and postflowering stage) gave 34.325 and 76.675 q/ha in basmati and non-basmati, respectively; both these treatments were statistically at par. These differences in yield were non-significant. The results indicated that the mechanical control of passing of 20–30 m coir or jute ropes, forwards and then backwards, both ways, while touching the crop canopy, offers a promising ecofriendly IPM option against rice leaf folder during the pre-flowering stage. Top Keywords Cnaphalocrocis medinalis, mechanical control, passing of ropes, pre-flowering period, insecticide sprays, post-flowering period, grain yield, IPM strategy. Top |