Efficacy of Fungal Antagonists as Seed Treatment in the Management of Meloidogyne javanica in Cowpea

A screen house study was undertaken to see the efficacy of two fungal antagonists viz., Trichoderma viride and Gliocladium virens as seed treatment against root-knot nematode, M. javanica infesting cowpea. The seeds of a susceptible cowpea variety Pusa Barsati were treated with laboratory propagated fungal cultures (spores and mycelia) @ 5 and 109/kg seed before sowing and subsequently root-knot nematode inoculation @ 1.0 J2/g soil was done one week after sowing. The results indicated that the growth parameters of cowpea plants, i.e. shoot length, fresh and dry shoot and root weight, were maximum and significantly higher in plants having seed treatment with T. viride and G. virens @ 10 g/kg seed followed by carbosulfan seed treatment (3% a.i., w/w) as compared to their lower dose i.e. 5 g/kg seed and untreated check which showed minimum and significantly lower plant growth parameters. The results of T. viride @ 109/kg seed were statistically at par with 10 g dose of G. virens. Nematode multiplication in terms of number of galls and egg masses was significantly reduced in carbosulfan followed by T. viride and G. virens @ 10 g/kg seed as compared to their lower dose and untreated check. Final soil population of J2, however, showed non-significant differences.