System of Rice Intensification: its present status, future prospects and role in seed production in India.

Abstract

System of Rice Intensification (SRI) as an alternate rice cultivation methodology, developed in Madagascar 25 years ago, is gaining wider acceptance in many countries including India. SRI method claims to greatly enhance water productivity and grain yield. But there is lack of understanding of scientific principles underlying and synergetic effects of the principles followed in SRI, especially in Indian conditions. The present paper is intended to discuss about significance and necessity of SRI along with performance of SRI at about 25 locations across the country for a period of four years. SRI was found to record 7-20% higher grain yield over the traditional irrigated transplanted rice in different agro-climatic situations of the country. SRI also recorded higher nutrient use efficiency without depleting soil available nutrients as compared to conventional transplanting after two seasons of the study. The varieties having better tillering ability as well as hybrids (KRH 2, HRI 126, PHB 71 and DRRH 2) were found promising and recorded higher grain yield over the high-yielding varieties and scented cultivars with moderate tillering. Root volume, dry mass and dehydrogenase activity in soil enhanced by 7-25% (measure of microbial activity) were found to be higher in SRI, compared with conventional method. There was reduction in seed rate by 80%, nursery area also obviously, water requirement by 29% and growth duration by 8-12 days, thereby enhancing water productivity and per day productivity of rice cultivars in SRI, which also proved to be helpful in producing more seed for faster seed multiplication and also quality seed for higher productivity. Water saving alone should be a strong justification for the adoption of SRI wherever water is not abundant. There is a need for further enhancing the rice productivity in SRI by identifying suitable cultivars, modifying practices to suit local agro-climatic conditions and understanding long term synergic effects among different practices.