Farmers in the village of Khanduthang had previously never heard of nor seen a crop of Dhaincha (Sesbania aculeta) now produce and sell its seeds to earn cash. It all started with the initiatives of the BUCAP [Biodiversity Use and Conservation Program] Project, which introduced this crop and trained farmers the art and skill of growing it.
Today, Dhaincha has been successfully introduced as a green manure crop for sustainable management of soil fertility in Khanduthang.
Khanduthang village under Samtse Geog is located in the wet subtropical agro-ecological zone with an altitudinal range of 150-600 masl. It receives an annual precipitation of 1,500 to 4,500 mm.
The intensity of precipitation is alarmingly high with most rain falling in less period of time. Such a high intensity rainfall washes away most of the fertile top soil due to heavy runoff and erosion. As a result, soil fertility and crop yields are declining at an unprecedented rate. The average yield of rice in Samtse Geog is 1,035 kg/acre (Agriculture Statistics, 2009).
Managing adequate levels of soil fertility is a major constraint in Khanduthang. Farmers largely depend on farmyard manure (FYM) as the only source of nutrients for crop production. However, being in the vicinity of Samtse Thromde (municipality), farmers cannot rear large numbers of livestock, which limits the availability of adequate FYM.
In light of this situation, farmers are in dire need of a more sustainable option for soil fertility management. To overcome this problem, the Research and Development Center (RDC) Bhur, as one of the BUCAP project stakeholders, introduced the cultivation of Dhaincha as a green manure crop in 2012. RDC Bhur supplied the seeds to all the 12 BUCAP project farmers and taught them to sow this crop in the rice field.
When the crop was in the vegetative stage, farmers were taught to incorporate it into the soil by ploughing it and allowing it to decay properly. After about a week, farmers were advised to transplant rice into those fields where Dhaincha was incorporated.
To the farmers’ surprise, rice yields improved quite noticeably in the plots where Dhaincha was used as a green manure.
With their success in the first year, BUCAP farmers expanded the cultivation of Dhaincha in 5.5 acres for green manuring and seed production.
To demonstrate the technology to more farmers, a field day was organized with the BUCAP farmers serving as the resource persons.
Dhaincha is now successfully adopted as a green crop by many farmers in Samtse Geog. The farming system has been diversified with a new leguminous crop that can help to improve soil fertility by fixing the atmospheric nitrogen.
Dhaincha has multiple uses. It can be used as a green manure, as fuel wood, and intercropped with ginger for seed production. BUCAP farmers have started seed production of Dhaincha and are earning cash from the sale of seeds.
The introduction of green manuring technology with Dhaincha is a cheap and sustainable option for soil fertility management. This will not only reduce the importation and use of inorganic fertilizers; it will also contribute towards achieving the country’s’ dream of becoming fully organic by 2020.
This story was lifted from HARVESTS: Farmers’ Success Stories, Copyright 2016 Bhutan National Biodiversity Center and Ministry of Agriculture and Forests