Farmers could one day control when crops ripen after the development of modified rice that flowers on demand.
Outdoor plants still develop according to the whims of nature — the warmth of early summer sun, the soft patter of spring rains — but Japanese scientists wanted to see if they could make them develop in response to the soft patter of something else: fungicide.
“If you can have a system to control flowering time, you can grow crops where you like,” Takeshi Izawa, of the University of Tokyo, said.
Growing conditions before and after flowering strongly affect the quality of harvest, so changing flowering time is key. “You can control the quality of the harvest, prolong growth and get a better yield,” he said.
He was particularly interested in how this might be useful in rice. Some commercial varieties of rice are grown only in certain parts of Japan, because of their different speeds of development.
“For example, there is a late variety,” Professor Izawa said. “If we try to make it in Hokkaido, northern Japan, the flowering becomes very late, in September. That means it is very cold and there is not enough time to harvest. If that rice could instead flower in early August, it would be able to produce a profitable harvest.”
For the same reason, controlling flowering in this way may also help to give Japan’s staple crop a buffer against climate change, he said.
Professor Izawa’s research, published in the journal Nature Plants, began by genetically engineering rice so that it never flowered. Then he and his colleagues tweaked the plants again so that mechanisms controlling flowering were switched on only by contact with a particular fungicide. A month and a half after being sprayed, the rice flowered. If it was not sprayed, it did not.
Advances in productivity have stalled. The yield per unit area of rice, for instance, has not changed in decades. However, with an estimated ten billion people set to be on the planet by 2050, efficiency must improve.
http://www.thetimes.co.uk/article/gm-crops-to-boost-yields-by-ripening-on-demand-3bm9q6jcd