Chinese Scientists Develop a Hybrid Rice That Can Be Replanted

JAKARTA - Chinese scientists have developed hybrid rice that in field trials is able to produce seeds with a genetic makeup almost identical to the parent plant. This finding has the potential to make the seeds from the harvest can be re-planted without losing high productivity.

China Daily, quoted Wednesday, July 29, reported that the research had been published in the journal Vita. The technology is still in the experimental stage and is not ready for commercial use.

Hybrid rice is the result of crossing two parent plants to obtain superior traits. Compared to ordinary rice, this type is known to produce higher and more resistant to poor growing conditions.

The problem is, the seeds of hybrid rice crops usually no longer carry all the superior traits of their parent plants. Seed companies have to produce new seeds every year through a complicated process and require a lot of manpower.

As a result, the price of hybrid rice seeds can be several times more expensive than ordinary rice seeds. In some cases, the difference is up to 10 times.

The research was led by Wang Kejian of the China National Rice Research Institute. His team discovered a natural gene called HUAXU that works like a switch to start the development of embryos or future plants in seeds.

"In field trials, more than 99 percent of the seeds produced plants with the same genetic makeup as the original hybrid rice," said Wang.

Wang's team began developing what is called a "single-line method" in 2013. The goal is that hybrid rice is made once, then its offspring can be re-planted year after year without losing superior traits.

In 2017, the team produced the first cloned hybrid rice seed. Cloning means producing a plant with the same genetic makeup as its parent.

The initial results are still limited. Only about 5 percent of the seeds are genetic copies of the parent plant. Wheat production has also dropped sharply.

After the HUAXU gene was discovered, the success rate increased to more than 99 percent. Seed production and harvest results remain normal.

Chong Kang, President of the Botanical Society of China and an academician of the Chinese Academy of Sciences, called HUAXU an almost ideal embryo activation switch. According to Chong, the gene helps scientists understand how plant embryos develop.

This technology is also considered to have the potential to change the way hybrid rice seeds are produced. Superior varieties are developed once, then can be re-planted for several generations. Seed costs and production risks can also be suppressed.

Li Jiayang of the Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, said the research overcomes a long-standing problem in plant breeding. Scientists previously had difficulty producing genetically identical offspring without disrupting the plant's ability to produce seeds.

"If hybrid rice can multiply itself, production costs and seed prices can fall sharply," said Wang Kejian of the China National Rice Research Institute.

Hybrid rice is currently grown on about half of China's rice fields, down from almost 70 percent at its peak. Outside China, its planting area is still less than 5 percent of total rice fields.

The results of the test do not mean that the seeds will be immediately available for farmers. Researchers still have to conduct safety tests, assess the long-term stability of the technology, and refine the system before using it in agricultural production.