Effect of 11 years long term manorial practices on nematode population and diversity in rice agroecosystem

Rice-rice is an important production system for eastern India. Soil organisms play important role in the functioning of rice field ecosystem. Fertilizer and manures directly or indirectly influence soil biota particularly faunal community and their functioning. The present investigation was undertaken to study nematode population and diversity under the influence of long term fertilizer experiment conducted on an acidic sandy loam Inceptisols of Bhubaneswar with eight numbers of manurial treatments. Nematode population and diversity studies were made on soils of pre planting, tillering and flowering stages of kharif 2017 taking treatment combinations of balanced nutrition (100%NPK), super optimal dose of balanced nutrition, secondary and micronutrient, organic manure (FYM) and soil conditioner (lime). The plant parasitic nematode population varied from 64 to 324/ 200 g soil. FYM @ 5t/ha and lime @ 1t/ha significantly reduced the parasitic nematode population at all growth stages of rice. Three parasitic nematode species i.e. Hirschmanniella oryzae, Helicotylenchus abunaamai, Tylenchorhynchus mashhoodi were identified to be present in the rice field irrespective of rice growth stages.