System of Rice Intensification
The System of Rice Intensification (SRI) is a methodology aimed at increasing the yield of rice produced in farming. It is a low water, labor-intensive, method that uses younger seedlings singly spaced and typically hand weeded with special tools. It was developed in 1983 by the French Jesuit Father Henri de Laulanié in Madagascar. The central principles of SRI are:
Rice field soils should be kept moist rather than continuously saturated, minimizing anaerobic conditions, as this improves root growth and supports the growth and diversity of aerobic soil organisms.
Rice plants should be planted singly and spaced optimally widely to permit more growth of roots and canopy and to keep all leaves photosynthetically active.
Rice seedlings should be transplanted when young, less than 15 days old with just two leaves, quickly, shallow and carefully, to avoid trauma to roots and to minimize transplant shock.
SRI is initially labour intensive
Needs 50% more man-days for transplanting and weeding.
Mobilises labour to work for profit.
It offers an alternative to the resource poor, who put in their family labour.
Once the right skills are learnt and implemented, the labour costs will be lesser.
SRI encourages rice plant to grow healthy with
Large root volume
More and well filled grain panicles and higher grain weight
Resists insects because it allows rice to absorb soil nutrients naturally
