Management of Post Harvested Paddy Crop Residues by Aspergillus Species for Sustainable Agriculture

Abstract

Rice, Oryza sp. (Angiosperm: Gramineae) is the mainstaple crop in the World and 493 million tons of ricewas produced world-wide, which supposed to be asource of main crop residue as per the report of IGC(International Grain Council) during 2017-18.Therefore, it was an urgent need to management of theresidue by the best suitable method i.e. biodegradationusing potent fungal species. The present study wasconducted to evaluate the potential mycobiota andanalyze the mechanism of action for the managementof post harvested crop residues for the sustainablegrowth. The findings of the current investigationreflected the pectolytic, lignolytic and cellulolyticactivities of Aspergillus species. The observed workedout may also prove that these mycoflora played a keyrole for biodegradation of paddy residues. During thecourse of study a sum of nine fungal isolates wererecovered from paddy residues (semicompostresource). Out of them, six isolates were selected on thebasis of their enzymatic activities against lignin, pectinand cellulose constituents of paddy straw. All the sixfungal isolates like A. nidulans, A. wentii, A. tamarii, A.fumigatus, A. flavous, and A. sydowii showed optimumlignocellulolytic activities, which were further used forin vitro decomposition of fresh paddy residue by theapplication of 10ml sample as spray on two gram offresh paddy residue and incubated at 28 ± 1ºC for 30days. At the end of 30 days experiment, the rate ofdecomposition was measured by ADR (Absolutedecomposition rate) and RDR (Relative decompositionrate). It was found that A. flavous showed highest ADRand RDR; however, A. fumigatus represented thelowest ADR and RDR. Thus, from the findings authorsare supposed to proposed and formulate a strategy forsustainable management of paddy crop residues. Thepractical application of the present study is assessed tobe a mile stone for the sustainable environment andnatural resources management to ecofriendlyagricultural activities and livelihood sustainability.