A second copy of a Chinese rice variety's own genes has boosted its yield by up to 40%. The group reported today in Science that the change helps the plant absorb morefertilizer, boost photosynthesis, and accelerate flowering, all of which could contribute to bigger harvests.

Matthew Paul is a plant geneticist who was not involved in the work. I don't think I've ever seen something like that before. He adds that the approach could be applied to other crops as well.

Many genes interact to influence the yield of a crop. For a long time, scientists have searched for genes that increase yield. They have shifted their interest to genes that control other genes, as well as multiple aspects of physiology, such as taking up nutrition from the soil, setting the pace of photosynthesis, and directing resources from leaves to seeds. A 10% higher yield is achieved by modifying one of the regulatory genes in maize.

A team led by a plant Biologist from the Chinese Academy of Agricultural Sciences combed through 118 rice and maize regulatory genes to find other yield boosters. Zhou and his team wanted to know if any of the genes were activated in rice grown in low nitrogen soil. The plant could draw in more nitrogen if they increased their activity in rice grown in regular soil.

13 genes that turned on when rice plants were grown in nitrogen-poor soil were found by the team. An extra copy of one of the genes was inserted into a rice variety that is used for research. The genes were knocked out in other rice plants. Plants with extra copies of OsDREB1C grew faster and had longer roots than plants with no extra copies.

Plants with extra copies of OsDREB1C took up more nitrogen through their roots and moved it to the shoots due to good nutrition. The modified plants had more of the plant's genes in their leaves and more of the plant's genes in its cells. The rice was grown in the field for 2 to 3 years and given higher yields at three different locations in China.

The researchers added an extra copy of the gene to transform a high yielding rice variety. The modified modern rice plants produced up to 40% more grain than the controls. Pam Ronald is a Rice Geneticist at the University of California, Davis. I think it's amazing.

The modified plants in the field had larger grains and more of them than the original plants. The result is a lot more convincing than improving a research variety because they took a very good variety and showed they could make it better.

The modified plants flowered earlier, giving them more time to make grain. Farmers can grow more crops per season or harvest crops before damaging summer heat sets in if the flower is faster. The widely farmed variety of rice bloomed two days earlier than the modified one.

Adding the rice OsDREB1C gene to a research variety of wheat yielded the same results. The OsDREB1C and similar genes are present in broad-leaved plants. The researchers found similar outcomes when they added an extra copy to the plant. It is consistent with a common role across the plant kingdom, suggesting other kinds of crops might be able to yield boost from this modification.

Some consumers don't like rice Zhou's team made. The same yield boost could be achieved by editing the plant's own genes. Ronald says that increasing nitrogen efficiency of crops could help reduce pollution of streams and lakes. Steven Kelly of the University of Oxford wrote a commentary about the importance of improved photosynthesis. If you have the right factor, you can get big jumps. There will be more.