Soil biological properties and fungal diversity under conservation agriculture in Indo-Gangetic Plains of India

Choudhary M, Sharma PC, Jat HS, Hanuman S, McDonald A, Jat ML, Choudhary S, Garg N. 2018. Soil biological properties and fungal diversity under conservation agriculture in Indo-Gangetic Plains of India. Journal of Soil Science and Plant Nutrition 18(4):1142-1156.

A field experiment was undertaken to evaluate the effect of conservation agriculture (CA) based management on soil biological properties, and on fungal diversity and abundance after 5 years of continuous cultivation. Treatments included four crop managements viz., conventional tillage (CT) rice-wheat (CT-RW; CT based), conventional tillage rice-zero tillage wheat and mungbean (CTR-ZTWMb; partially CA based), zero tillage rice-wheat-mungbean (ZT-RWMb; full CA based), and zero tillage maize-wheatmungbean (ZT-MWMb; full CA based). Full rice, maize, and mungbean crop residue and anchored wheat residue were recycled in CA-based managements, while CT-based management was without any residue. Full CA-based management (ZT-MWMb) recorded 43% higher organic carbon, 56% microbial biomass carbon, 70% microbial biomass nitrogen, 73% phosphatase activity, and 40% β-glucosidase activity, than CT-RW management. Ascomycota (55-74%) was the dominant phylum followed by Basidiomycota and Glomeromycota (0 to 3%); abundance of these phyla varied amongst managements. Ascomycota abundance was in order of CT-RW< CTR-ZTWMb< ZT-RWMb< ZT-MWMb, however, Basidiomycota and Glomeromycota did not follow any trend. Diversity indices such as species richness, evenness and Shannon-Wiener diversity index were in the order: ZT-MWMb> ZT-RWMb> CTR-ZTWMb> CT-RW. This study clearly showed that CA with all three proven principles (no-tillage, residue retention and crop diversification) in maize-wheat-mungbean system resulted in higher microbial activities, fungal diversity and species richness compared to other cereal based management systems.