Although grain soybean grown for oil and meal is the largest legume crop in India, until recently vegetable soybean was virtually unknown in the country. That began to change when AVRDC - The World Vegetable Center, the Indian Council of Agricultural Research (ICAR) and 6 NGO partners in Ranchi and Khunti districts of Jharkhand encouraged farmers to expand production of the crop as part of a Sir Ratan Tata Trust (SRTT)-funded project to improve vegetable production and consumption in the region.
In East Asia, the large seeded, sweet type of soybean (Glycine max) has been consumed as a fresh vegetable for centuries. Immature pods are boiled in salted water and the extracted seeds serve as a nutritious snack food.
Green vegetable soybean seed has up to 13% protein on a fresh weight basis and high levels of healthy monounsaturated fatty acids, and vitamins C and E; it is also one of the few natural sources of anti-cancer isoflavones. Cooked vegetable soybean has the highest net protein utilization value (NPU; the ratio of amino acid converted to proteins) among all soy products, and when combined with rice, supplies complete protein to the diet.
With almost double the protein and 6 times the energy content of green peas, India’s most commonly consumed fresh legume, vegetable soybean also has 60% more calcium and twice the phosphorus and potassium levels. While green peas are available only in the cool season, vegetable soybeans are picked in October – a festival month in Eastern India when few other legumes are available and prices are high.
Vegetable soybean is particularly important to tribal communities. Numbering over 82 million, tribal people are the most disadvantaged group in India with the worst nutritional status. Tribal people constitute the largest percentage of the population in the states of northeast India, such as Jharkhand. They do not consume dairy products and overwhelmingly rely on legumes to provide most of their protein requirements.
It began circulating in northeast India during the millennium decade of 2000-2010. The first vegetable soybean varieties suited to local conditions were identified in 2001. The introduction of improved AVRDC lines led to the release of the variety ‘Swarna Vasundhra’ in 2008 by the ICAR research station in Jharkhand. The hardy crop has low labor requirements and is well-suited to the sandy and often shallow soils of Jharkhand. This new variety was distributed to 60 farmers in 2008, and promoted through field days and training events. The following year, 470 farmers grew the crop; by the third year more than 3000 farmers were growing vegetable soybean and by the fourth year demand from 50,000 farmers for seed greatly outstripped available supplies.
Mr. Khudiram Munda, a 31-year old farmer from the tribal village of Uludih near Ranchi in Jharkhand is typical of many new vegetable soybean growers. He sowed 4 kg of seed provided by AVRDC in July 2010 in a 400 m2 field. He harvested 250 kg of green pods about 80 days later and sold them to four nearby local markets for INR20/kg (US$0.37/kg).
“My children like the taste [of vegetable soybean] and I like it because it has vitamin A, which is good for the eyes.”
Mr. Munda’s family consumed the green vegetable soybean seeds boiled like green peas. They found the dry seeds could be very tasty if soaked overnight to remove the seed coat, then fried with ginger, garlic, turmeric and other spices and eaten with rice. It has now become an important source of income and food for his family. Vegetable soybean seed also can be cooked as dhal – a staple legume porridge.
Six members of Jeevanba mahila mandal, a 15-member women’s self-help group from Iti village, grew vegetable soybean on an average of 10 decimals of land. Almost 50% of pods at green stage were consumed as curry. “We liked it very much,” the members said. “The rest we have kept as seed for cultivation next year, and we will return back some seed to PRADAN’s Agriculture cooperative for multiplying in other areas.”
In an SRTT evaluation of the project, 93% of families cited taste as a motivating factor to cultivate vegetable soybean, and more than 70% of farmers were impressed with yields of ‘Swarna Vasundhra.’ The nitrogen the crop produces that is fixed in the soil also benefits subsequent crops. Taking these factors and the value of seed sales into account, SRTT estimated that net income can be increased by around INR1700/kg (US$31.5/kg) of seed planted in a 400 m2 field.
AVRDC is now testing 16 new vegetable soybean lines with a wide range of seed colors and qualities in trials across India. Some lines have a “basmati rice” flavor – a popular taste that commands a high price. Two new high yielding varieties are ready for official release. The main effort now is to increase production of vegetable soybean and to continue promoting its consumption in Jharkhand to create a strong and permanent demand for this new crop.