Published a complete map of the genetic variation of rice

A research team from China and Japan has published a complete map of the gene variants of rice, which supplies food for half of the planet's population.

Research shows that the current major variety of rice originates from the delta of Guangdong and Guangxi provinces of China.

The study, published in the October 3 issue of the journal Nature, is the result of a thorough analysis of DNA genetic codes of more than 1,000 rice varieties (including two indica and japonica subgroups) and nearly 500 Wild rice varieties (belonging to the Oryza rufipogon group), ancestors of the current rice varieties.

According to studies, the vast majority of currently grown rice belongs to Oryza sativa L., collectively known as 'Asian rice', which is divided into two sub-groups, indica and japonica.

The rice belongs to the short and sticky japonica sub-group (ie sticky rice), while the indica sub-group has long and non-sticky seeds (ie, glutinous rice).

One point agreed by the researchers in the group is that the current cultivated rice is derived from the wild rice Oryza rufipogon, thousands of years ago.

However, the origin and process of this rice domestication is still the subject of debate.

Regarding the origin of the Oryza sub-group sativa japonica, which is the first rice variety, studies have shown that this rice variety is domesticated from wild rice plants in southern China, the central area of ​​the delta. Chau Giang, belongs to Guangdong and Guangxi provinces today.

Next, the rice variety of the japonica sub-group was crossed with wild rice species in Southern Asia and Southeast Asia to form rice varieties of the indica sub-group.

Currently, there are about 155 million hectares of rice in the world, producing 720 million tons of rice / year, in 90% in Asia.

According to some predictions, to ensure food security for an important part of the global population, rice yields must double by about 2030 and need to develop higher yielding rice varieties.

In addition to the two major varieties of rice varieties mentioned above, in Africa there is a small rice variety, with the scientific name Oryza glaberrima, commonly known as 'African rice'.