A research team from the Institute of Genetics and Developmental Biology under the Chinese Academy of Sciences has studied the relationship between the feeding behavior of birds and sorghum. They found the bird feeding behavior was controlled by a single gene in sorghum, called Tannin1.

The gene regulates the synthesis of tannins, a kind of bitter-tasting compound in plants, as well as bird-attracting volatile organic compounds derived from fatty acids, according to the paper.

The researchers found that the sorghum avoided by birds contains Tannin1, while the bird-preferred sorghum has a mutated version of the gene.

Tannin1 can be an efficient means of protecting cereal crops worldwide, said Xie Qi, leader of the research team.

Cereal crops most vulnerable to bird damage include wheat, barley, rice, sorghum and millet. Farmers often use anti-bird nets to protect field crops. But the method requires considerable manpower and material cost, and risks harming birds.

The researchers sprayed organic pesticide containing tannins before the maturity of sorghum. "The organic pesticide is used in extremely low quantities and can be resolved in water and degraded in nature," explained Xie.

To ensure the birds' survival and maintain ecological balance, the researchers promised to grow certain areas of sorghum without spraying the organic pesticide in neighboring crop fields.

"Our ultimate goal is to develop sustainable agriculture and husbandry," said Xie.