INNOVATIONS TO REDUCE SRI LABOR REQUIREMENTS
The "Ariyatne Weeder"
Mr. Ariyatne Subasinghe, from Hingurakgoda, Sri Lanka, is shown here with the labor-saving motorized weeder he designed. He is cultivating 5 acres (2 ha) with SRI methods and finds it difficult to do as many weedings as recommended for such an area. So he has developed this weeder, with a Chinese motor, that he can make for about $750, and which he considers a cost-effective innovation given the yields he can get with SRI methods. (Click on photo to enlarge the picture).
An even more interesting innovation is a method of crop establishment he is using this season, similar to one that Mr. Ramasamy Selvam in Tamil Nadu state of India has started. The goal is to save the labor needed to construct and operate a nursery and to do manual transplanting, while still capitalizing on the benefits of other SRI practices.
Ariyaratne broadcasts germinated seed at the rate of 25 kg/ha onto a muddy paddy field. The resulting plants are more dense than the 5-10 kg/ha rate with transplanted SRI, but they are less dense than with the more usual broadcasting rate of 50-150 kg/ha.
At 15-20 days, he does a 'first weeding' which reduces the plant population as well as any weeds in the field. By doing this in the usual SRI pattern of perpendicular passes of the weeder, he leaves preferably 1 plant, but possibly 2, at intersections 25x25 cm or 30x30 cm across the whole field. This creates a plant population similar in number and spacing to what would be achieved with the presently recommended transplanting method.
He continues to do additional weedings as needed to control weeds and aerate the soil. His motorized weeder makes this task much easier and quicker. Mr. Selvam in Tamil Nadu broadcasts young seedlings, about 10 days old, rather than germinated seed, and then eliminates 'excess' plants not growing at the desired 25x25 cm intersections by his first weeding.
Farmers with very small paddy holdings, who need to maximize their yield per hectare, will get the most benefit from the recommended careful transplanting of young seedlings. But farmers with larger landholdings, who benefit most from maximizing their returns per hour of labor, may find this modification of SRI practice advantageous, spending more for seed but reducing their labor cost.
SRI is still a work in progress. These kinds of farmer innovations are going to make it even more beneficial and adoptable. We encourage anyone with ideas or, even better, validated practices that can better utilize the principles of SRI to communicate them to us: sririce@cornell.edu or tefysaina.tnr@simicro.mg