Science of hybrid rice:
breeding, cropping patterns and the environment
Hybrid rice yields 15-20% more than inbred varieties in Vietnam
(in Vietnamese; pdf)
International Workshop on: gHybrid rice and agro-ecosystemh held in Hanoi has recommended the yield of hybrid rice is higher than that of inbred varieties from 15 to 20%.
The workshop was organized by cooperation between Hanoi University of Agriculture (HUA) and Kyushu University (KU), funded by the Japan Society for Promotion of Science (JSPS) Platform Project and HUA in 23-24 November 2007. The participants were experts from Vietnam, Japan, Philippines, India, Bangladesh, Germany, and USA.
Hybrid rice has been firstly planted in Vietnam since 1991. Nowadays, total cultivated area of hybrid rice is 600,000 ha annually with average yield of 6-6.3 ton per ha, which is higher than yield of inbred varieties 15-20%. The F1 hybrid seed production has also opened a change to increase income for farmers. Hybrid rice contributes to food security in many provinces in the North and Central of Vietnam.
In recent years, HUA has some successes in hybrid rice research and development. These achievements are resulted from collaboration between HUA and international organizations such as FAO, IRRI, Chinese research institutes, and KU (Japan).
Dr. Tran Duc Vien, the rector of HUA, said gVietlai 20, which was created by HUA scientists, has been released as the first national hybrid variety of Vietnam in 2004. Then, other hybrid rice varieties were created such as TH3-3, TH5-1, TH 3-4 and Vietlai 24, which also were accepted as national varieties and planted in a large-scale area of several ten thousand ha.h
In order to develop hybrid rice, the scientists need to create combinations of hybrid rice, which has good characteristics such as good quality, stable yield and disease resistance. Although Vietlai 20 has a shot growth duration and high grain yield, it is still susceptible to bacterial blight of rice (BB). According to Dr. Atsushi Yoshimura, Kyushu University and other scientists, Xa21 (BB resistance gene) can be transferred into the sterile line 103S by using back-crossing and molecular marker-assisted selection. Hopefully, by using this method, Vietlai20, a 90-day hybrid variety, will give 8-9 t/ha.
In the workshop, several sustainable solutions for hybrid rice developments have been recommended. They are capacity building in research, hybrid rice breeding, seeds management in Vietnam. In addition, hybrid rice breeding is an effective strategy to adapt diversity of geography, climate and social context and to exploit wider rice genetic resources.
A new method of fertilizer application, which is applied compound fertilizers in deeper layer of the fields, has developed by HUA scientists. This method can reduce the cost of production and amount of fertilizer, and increase up to 20% rice yield to compare with conventional methods. The new method will contribute for agricultural sustainable development as well as environmental protection.iTranslated by Tang Thi Hanhj