Catenaria anguillulae Sorokin:: a natural biocontrol agent of Meloidogyne graminicola causing root knot disease of rice (Oryza sativa L.)

Catenaria anguillulae parasitized and killed the eggs and second stage juveniles (J(2)) of Meloidogyne graminicola under natural conditions. The percentage of infection in eggs was higher than J(2) of M. graminicola, which ranged between 0-50.3% and 0-18.9% in 2004 and 0-46.6% and 0-21.7% in 2005, respectively. The higher parasitism of eggs and J(2) was recorded from those fields in which plants were severely infected with M. graminicola. The degree of parasitism of eggs and J(2) by C. anguillulae varied with severity of root knot disease. The fields with a higher root gall index recorded a higher percentage of infection in eggs and J(2) of M. graminicola. In general, old galls when teased and incubated, recorded higher parasitism of eggs and juveniles than young galls.