Effects of SRI practices on hybrid rice performance in Tamil Nadu, India

Abstract

Nadu Agricultural University, Coimbatore, India, to test components of the System of Rice Intensification (SRI) using hybrid rice variety CORH2. The following four factors were studied: seedling age (14-d-old seedlings vs 23-d-old seedlings), irrigation (limited vs conventional), weeding (weeds incorporated with a conoweeder vs manual removal of weeds), and nutrient management (recommended amount of fertilizer with and without green manure). The experiment was a strip-plot design in four replicates. The results show savings in irrigation water of 56% and 50% using conventional and young seedlings, respectively, without a significant effect on grain yield. The average grain yield for the limited irrigation treatment (6,352 kg ha–1) was not significantly different from that of the conventional irrigation practice (6,461 kg ha–1). No significant main effect of seedling age and nutrient management was found. In situ incorporation of weeds increased yield significantly to 6,737 kg ha–1 compared with that of conventional weeding of 6,076 kg ha–1. A significant interaction was found among weeding, seedling age, and nutrient management. The highest yields for both conventional and limited irrigation conditions were obtained with a combination of young seedlings, green manure application, and incorporation of weeds using a conoweeder. This implies that our attempts to reduce water use in rice cultivation will have to be accompanied with a set of appropriate agronomic measures.