In a world’s first, a consortium of researchers in Andhra Pradesh has developed a sweet sorghum hybrid that yields both fuel and food. While biofuel, which can partially replace petroleum as vehicle fuel, is welcomed the world over, experts have a major concern: foodgrain crops are diverted as raw material for this alternative fuel. This, they say, is already seriously compromising food security with prices of several crops such as corn and sugarcane shooting up.

But the production of the first ever batch of ethanol from the stalks of a new sweet sorghum variety in an Andhra Pradesh distillery this month stands out.

Ethanol here is produced from the sweet juice in the stalk of the sweet sorghum, leaving the grain to be used as food. The researchers who developed the hybrid say resource-poor farmers will benefit from this as they will still be able to use the sorghum grain and earn an additional income selling the stalks.

The hybrid was developed by a consortium led by Belum V.S. Reddy, principal sorghum breeder of the International Crops Research Institute for Semi-Arid Tropics (ICRISAT) at Patancheru, Andhra Pradesh.

Sweet sorghum is a cheap biofuel crop to grow, with a cost that is one-fifth of that of sugarcane. It also requires half the water needed to grow maize and about an eighth of that required for sugarcane.

It is also carbon neutral. Which means that the plant, during its entire life and eventual combustion as ethanol, emits only that much carbon dioxide that it has taken in during its growth.

When sweet sorghum biofuel is blended with petrol, it also emits less polluting sulphur and nitrous oxides compared to sugarcane biofuel, says Reddy.

A major problem was ensuring availability of sweet sorghum stalks throughout the year. “Different plant types produce different amounts of juice at different times of the year and it is important to have genetic stocks that can produce the same amount of juice throughout the year,” says Reddy.

ICRISAT solved the problem by developing hybrids that can be planted at any time of the year. The team intends to plant at least 4,000 acres of the new crop during the next rainy season, according to G. Subba Rao, director of Aakrithi Agricultural Associates of India, a partner in the project.