Bioefficacy of Obligate Bacterial Parasite, Pasteuria penetrans Against Root-Knot Nematode, Meloidogyne incognita Infestation in Chilli

Root-knot nematode, Meloidogyne incognita is a major plant parasitic nematode which has a wide host range. It attacks most of the horticultural crops and causes considerable yield reduction. Carbofuran is the only effective nematicide available in market till date. Among non-chemical management methods, bio-control is gaining importance now days due to its eco-friendly nature. Pasteuria penetrans is a bacterial parasite specific to nematodes. Root-knot nematode often spreads from nursery to main field through infected seedlings. Hence a study was conducted to restrict the root-knot nematode multiplication in main field through nursery treatment with P. penetrans. Seedling pans were filled with sterilized soil and inoculated with eggs of M. incognita at the rate of 10000/pan. Endospores of P. penetrans were collected from nematode infected root-knot galls. Dried root powder was prepared from these galls which contained P. penetrans spores. Three treatments viz., 0x10⁶ spores (control), 0.5x10⁶ and 1x10⁶ spores/pan were tested. Seeds of chilli (cv.K2) were sown in the seedling pans. Seedlings were transplanted to micro plot (1m²) filled with methamsodium-treated sterilized soil. Soil nematode population, egg masses production, root galls and percentage of second stage juvenile (J2) parasitized were recorded. Soil nematode population was significantly reduced by 18.4 percent at 35 DAS, 74 percent at 90 DAS and 88 percent at 210 DAS. Egg mass production was 91 percent lower in P. penetrans spores (1x10⁶) treated soil when compared with control.