Farmyard Mulching in Regenerative Agriculture Enhances Saprotrophs and Concomitantly Reduces Pathogenic Fungal Genera

Regenerative agriculture (RA) using nature-friendly methods nurtures soil microbial communities. Indian RA farmers use diverse practices to manage their soil. This study compared the fungal communities in RA plots with those in conventional agriculture (CA) and barren land (BL) plots (comprising completely barren-BL and with Eucalyptus - BL-Euc). Two crops were considered - Finger millets and Vegetables (Tomato/ beans) for this study. ITS metagenomic analysis of soil DNA samples obtained from RA, CA and BL plots was done to identify fungal composition in each of the study plots. The fungal communities in RA finger millet and RA vegetable were compared with respective CA finger millet and CA vegetable and with BL plots. Vegetable RA plots observed higher abundances of fungal Operational Taxonomic Units (OTUs) than in CA vegetable and BL plots. Whereas the RA finger millet plots had similar fungal OTUs as in CA finger millet and BL plots. The vegetable RA plot carrying out natural farming for 12 years (maximum length in our samples) recorded the highest fungal OTU (13707) levels while the CA plots had average OTU abundance of (7416). RA plots in both crops showed a significant reduction in plant pathogenic fungal genuses - Bipolaris and Pyrenochaetopsis. Furthermore, RA finger millet plots showed an enhanced representation of saprotrophs while CA (finger millets) had pathotroph-saprotrophs suggesting a favorable increase in decomposer populations in RA.