Rice is one of the largest sources of human energy on the planet providing near one quarter global energy per capita. As such, researchers have looked for ways to manipulate rice and increase throughput. One group with educational roots in Nanjing, Hangzhou, and Beijing found a rare allele in rice, qgl3, that produces longer grain rice.
This is not the first time, however, rice has been put under the genetic microscope. Back in 2000, an article was published in Science that detailed genetically modified rice made to contain beta-carotene, a vitamin-A precursor. “Golden rice” as it was deemed was seen as a great breakthrough by some and frowned upon by others. Perhaps this larger strain of rice will attract similar attention.
Rice grains range from 5mm to 10mm depending on strain. In these project, researchers crossed extra long grain rice, N411, with a backcrossed strain containing the rare gene. Growing the plants resulted in grains averaging 12.22mm in length. Compared to the control rice, 93-11, this was a 2mm increase.
A closer look at qgl3 revealed that the hybrid N411-qgl3 strain grew longer because of increased longitudinal cell numbers. This was also hypothesized to be the reasoning behind the heavier grains observed.
If the qgl3 gene is crossed more universally, elite grains of rice may be bred. It is estimated that 5,000 liters of water is needed to produce one kilo of rice. With this superior rice, higher yields will be observed for an unchanged amount of biological material put in.
Xiaojun Zhang, Jianfei Wang, Ji Huang, Hongxia Lan, Cailin Wang, Congfei Yin, Yunyu Wu, Haijuan Tang, Qian Qian, Jiayang Li, Hongsheng Zhang. 2012. Rare allele of OsPPKL1 associated with grain length causes extra-large grain and a significant yield increase in rice. PNAS.