System of Rice Intensification
The system of rice intensification (SRI) is a package of improved practices for growing rice crop. It was first conceptualized in Madagascar by Father Henri Laulanie in 1983. It is essentially a water-smart technology saving up to 20-50% water. Irrigated medium lands in the wet season and the dry season, rainfed shallow lowlands where water control (irrigation and drainage) is possible, irrigated boro/ rabi rice, favourable bunded uplands during the wet season are suitable for SRI. It encompasses a set of five simple principles work synergistically to enhance yield:
- Transplanting at the early age, more preferably seedlings of 8-12 days are suitable, when the plant has only two small leaves, before the fourth phyllochron.
- Transplanting of a single seedling per hill and wider spacing in square fashioned is practiced. Seedling still attached with the seed, transplanted at 1-2 cm keeping roots at horizontal position planting at grid point demarcated by a marker.
- Mechanical weeding (rotary hoe/ conoweeder) for 2-3 times is recommended. The first series of weeding to be completed at 10 DAT (days after transplanting) and others in a frequency of 10-15 DAT.
- Maintenance of moist soil under non-saturated conditions during the vegetative phase, which results in the development of more tap and primary roots.
- Application of organic manures for optimum biological activity and continual release of nutrients.
The major benefits of this technology are
lower seed requirement (5 kg/ ha),
water-saving (20-50%), very high yields (35-40%), improved soil health, improved input use efficiency
and lower methane emission (50-60%).