SCREENING AND EVALUATION RICE VARIETIES /LINES FOR RESISTANCE AGAINST ROOT-KNOT NEMATODE, MELOIDOGYNE GRAMINICOLA.

Screening of some rice varieties were tested for their resistance against rice root-knot nematode (Meloidogyne graminicola). The investigation was conducted on 50 rice varieties along with LALAT as local check , which showed evidence of damaging potential of Meloidogyne graminicola in terms of plant growth parameters and disease incidence. Disease intensity grade was classified on the basis of root knot index. Out of fifty varieties,45 were moderately resistant to Meloidogyneincognita while 3 varieties Ciherang Sub 1,IR 64 Sub 1and PSBRC 18 were susceptible with maximum number of egg mass per galls (6) while the rest 2 varieties ,IRIOF 571 & IRIOF 602 showed resistant reactions.Possible reasons for reduction of shoot weight and root weight in infected plant may be due to improper supply of nutrients resulting from nematode infection for which it is compensated to some extent in resistant varieties.