Soil nematofauna diversity of paddy fields of Goa, India

Paddy field is a specialized habitat in which the soil has a very high water-holding capacity. Many nematode taxa are present in paddy fields including those that are specific parasites of the roots, stem and leaves of rice plants. Twenty-five species of nematodes were identified, belonging to five orders, 15 families and 19 genera. Nematodes were aggregated, not randomly or uniformly distributed. Herbivores belonging to order Tylenchida were most abundant. Peak densities and high diversity were in morod lands (rain-fed uplands) and in kher lands (rain-fed midlands) than in khazan lands (coastal saline lowlands). Higher densities and diversity were in the soil samples collected prior to paddy harvesting and lower in soil samples collected before transplant and after harvest. Hirschmanniella oryzae and H. mucronata were the dominant plant parasites.