Abstract

Investigations were undertaken in the farmer's field, Ariyalur district of Tamil Nadu during rabi and summer seasons of 2015–16 on lateritic soil to evaluate the effects of graded levels of lignite flyash (LFA) on nodulation pattern of groundnut and biological properties of soil. The results of the field experiment revealed that among the various graded levels of LFA evaluated, combined application of LFA @ 5 t/ha+FYM @ 10 t/ha + RDF had recorded the highest results in terms of their ideal physico-chemical characteristics, the magnitude of nutrient contents and their availability, and microbial population and nodulation pattern of groundnut during both the seasons. Application of LFA @ 5 t/ha+FYM @ 10 t/ha+RDF recorded the highest count of bacteria (36.80 and 38.30 million/g of soil), actinomycetes (1.46 and 1.58 million/g of soil) and fungi (15.25 and 16.45 million/g of soil) in post-harvest soil during rabi 2015 and summer 2016, respectively. LFA in combination with FYM gave better results than LFA applied alone. Increased dose of LFA application was found to be inhibiting the multiplication of different groups of microbes.