Differential Response of Rhizosphere Microbial Diversity and Activities to System of Rice Intensification and Conventional Cultivation

Rice holds a vital position among staple crops worldwide, serving as a primary source of essential nutrition for a significant portion of the global population. Rice production is currently plagued by several problems causing a decline in crop yields. System of Rice Intensification (SRI) is a set of farming practices designed to improve the productivity and sustainability of rice cultivation. One of the reasons for the sustainability of SRI has been attributed to enhanced below-ground soil microbial processes around the SRI plant root system. This study assessed the effect of SRI and Normal Transplanting (NTP) cultivation methods on rhizospheric soil microbial populations, phyto-hormones, soil enzyme activities under four different nitrogen (N) treatments under a station trial and in on-farms experiments farmer’s. Rhizosphere soils and root samples of SRI exhibited significantly higher microbial population, microbial diversity, phyto - hormone production, enzyme activities in station trail. Among different levels of nitrogen fertilizer applications, treatments receiving 50% organic + 50% inorganic N forms possessed significantly higher microbiota and their activities. On farm trials also exhibited similar trends as the station trial. In conclusion, the study highlights the positive effects of SRI cultivation combined with a balanced organic and inorganic nitrogen treatment on soil microbial populations and phyto-hormone production and soil enzyme activities which could have an influence of system sustainability.