Abstract

In the recent past, rice root-knot nematode, Meloidogyne graminicola has attained wide importance due to its potential to cause major damage in rice-wheat cropping system. It has become an emerging problem in the nurseries and upland rice along with its widespread occurrence in the deepwater and irrigated rice in the different countries of Southeast Asia. Second stage juveniles (J2s) penetrate the roots closely behind the root tip; migrate to vascular cylinder turning it into multinucleated giant cells, by endomitosis and cell hypertrophy characterized by hook shaped galls. This nematode is remarkably well adapted to flooded condition as it can survive in the aerenchymatous tissue of the graminaceous plant in flooded condition.

Key words: Continents, incidence, loss/damage, rice-wheat cropping sequence.