Scientists have successfully developed and tested a hybrid wheat breed that could at least double China's present per-hectare yield.
The hybrid marks another breakthrough in the problem of feeding a country of 1.3 billion, after the development and wide use of high-yield hybrid rice varieties in recent years.
The highest yield per-hectare of the wheat breed is 10.7 tons, nearly 6.5 tons more than China's average per unit yield of wheat in 2004, said Zhai Huqu, president of the Chinese Academy of Agricultural Sciences and head of the research team.
The world-record setting wheat breed beats the previous yield high set by the Netherlands by 2.5 tons. The world's average yield per-hectare in 2004 stood at only 2.8 tons.
In an exclusive interview with China Daily, Zhai and the team's lead scientist Liu Binghua said they were releasing the achievements for this first time since obtaining new experiential data last autumn.
"Experimental findings have shown that it's really a super wheat breed and is set to nearly triple the current per unit yield," Zhai said, adding the new breed will help meet China's growing demand for grain.
His team submitted a proposal to the central government, suggesting the new breed be planted in nearly one fourth of China's wheat fields by 2008.
According to Liu, the central government has agreed to launch a national program, involving 300 million yuan (US$36 million) taken from the nation's coffers, to expand pilot breeding and planting in China, where wheat accounts for 25 percent of total grain consumption.
Seed companies applauded the achievements but have expressed concern over whether the high-yield hybrid can be localized.
"Different regions vary in weather and soil conditions so the hybrid may see different results in different areas," said Zhong Dingxu, general manager of Deyue Seeding Company in Deyang of Southwest China's Sichuan Province.
But Liu said the experiments in Jiangsu, Henan and Beijing have all shown that the variety -- Lunxuan 987 -- which was successfully developed by his team in July 1998, performed well in various regions.
The per unit yield of 10.7 tons in Jiangsu was the highest, followed by 9.1 tons per hectare in test fields in the Changping District of Beijing and almost 10 tons in Xinxiang of Central China's Henan Province.
In China, wheat is widely grown in northern and parts of southern areas of the country.
"The government has supported us in testing the variety nationwide this year, even in high-altitude regions including Tibet and I am confident more experiments will further prove its high yield across the country," said Liu.
"We can improve genetic traits of the variety in line with local conditions when we plant in different regions," he added.
Liu said his confidence came from a set of practical and quantitative cyclic wheat breeding methods and techniques which can greatly improve wheat properties such as resistance to creeping and disease, high yield and quality.
"We have produced several hybrid wheat varieties by using modern breeding methods and Lunxuan 987 is the most outstanding one," said Liu, who has been buried in wheat breeding research since the 1970s.
Lunxuan 987 has a stalk height of 85 centimeters, features a resistance to lodging, powdery mildew and stripe rust and is able to shed its yellow leaves when ripening.
"All the traits resulted from 10 rounds of screening and selected gene insertion," said Liu, adding that today's achievements can date back to 1972, when an agricultural researcher in Taigu County of Shanxi Province happened to find a stalk of wheat of a particular genetic variety in a field. The wheat was later named Taigu infertile wheat because of the complete infertility of its stamen and the pistil's easy access to pollen.
Liu said Taigu wheat was at that stage the most satisfactory infertile material for hybrid wheat breeding because its infertile stamen created opportunities for the pistil to cross-pollinate with other wheat of better genetic traits.
The next generation of the Taigu variety consisted of wheat that was half infertile and half fertile. But they were of the same height and it proved difficult to tell them apart.
So Liu decided to use a marker.
The infertile wheat was crossed-pollinated with genetic marker Aibian I, a brand of wheat only 35 centimeters in height, and from it a new breed with a short stalk and male infertility was born.
This new generation was called Aibai wheat, and was identifiable by its low stature, meaning infertile wheat was shorter than its fertile cousin.
Aibai wheat kept its male sterility, strong stalk and particular look and became a desirable cyclic screening tool for wheat breeding.
The next move for Liu's team was the insertion of Aibai wheat genes into many other wheat varieties with ideal genetic traits. The rotational screening could begin.
Lunxuan987 was one of the products of this process and incorporated the genetic properties of many wheat breeds. "But we are continuously improving its properties, and now we are trying to make it tolerant to drought," said Liu. He admitted, however, that the quality of flour made from Lunxuan987 is not the best in China, but it could be used as a grain ration or an industrial resource.
(China Daily April 4, 2005)
