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WASHINGTON, May 2 (Xinhua) -- Rice originated in China, a team of U.S. genome researchers has concluded in a study tracing back thousands of years of evolutionary history through large-scale gene re-sequencing.Their findings, which appear Monday in the latest issue of the Proceedings of the National Academy of Sciences (PNAS), indicate that domesticated rice may have first appeared as far back as approximately 9,000 years ago in the Yangtze Valley of China. Previous research suggested domesticated rice may have two points of origin -- India as well as China.Asian rice, Oryza sativa, is one of world's oldest crop species. It is also a very diverse crop, with tens of thousands of varieties known throughout the world. Two major subspecies of rice -- japonica and indica -- represent most of the world's varieties. Sushi rice, for example, is a type of japonica, while most of the long-grain rice in risottos are indica.Because rice is so diverse, its origins have been the subject of scientific debate. One theory -- a single-origin model -- suggests that indica and japonica were domesticated once from the wild rice O. rufipogon.Another -- a multiple-origin model -- proposes that these two major rice types were domesticated separately and in different parts of Asia. The multiple-origin model has gained currency in recent years as biologists have observed significant genetic differences between indica and japonica, and several studies examining the evolutionary relationships among rice varieties supported more than domestication in both India and China.In the PNAS study, the researchers re-assessed the evolutionary history, or phylogeny, of domesticated rice using previously published datasets, some of which have been used to argue that indica and japonica rice have separate origins. Using more modern computer algorithms, however, the researchers concluded these two species have the same origin because they have a closer genetic relationship to each other than to any wild rice species found in either India or China.In addition, the study's authors examined the phylogeny of domesticated rice by re-sequencing 630 gene fragments on selected chromosomes from a diverse set of wild and domesticated rice varieties. Using new modeling techniques, which had previously been used to look at genomic data in human evolution, their results showed that the gene sequence data was more consistent with a single origin of rice.In the study, the investigators also used a "molecular clock" of rice genes to see when rice evolved. Depending on how the researchers calibrated their clock, they pinpointed the origin of rice at possibly 8,200 years ago, while japonica and indica split apart from each other about 3,900 years ago. The study's authors pointed out that these molecular dates were consistent with archaeological studies.Archaeologists have uncovered evidence in the last decade for rice domestication in the Yangtze Valley beginning approximately 8, 000 to 9,000 years ago while domestication of rice in the India's Ganges region was around about 4,000 years ago."As rice was brought in from China to India by traders and migrant farmers, it likely hybridized extensively with local wild rice," explained New York University biologist Michael Purugganan, one of the study's co-authors. "So domesticated rice that we may have once thought originated in India actually has its beginnings in China."

BEIJING, Feb. 8 (Xinhuanet) -- China's railroads and highways will see their busiest day of the Spring Festival holiday on Tuesday when the number of travelers returning to major cities hits its peak, just as a cold snap sweeps across much of the country, the ministries of railways and transport said on Monday.The Ministry of Railways said on its website that there had been a sharp rise in the number of travelers leaving smaller cities on Monday bound for such places as Beijing, Shanghai and Guangzhou.The ministry said the number of people on the move on Tuesday is likely to make the day the Spring Festival travel peak.The nation's roads are also likely to be at their Spring Festival maximum on Tuesday and Wednesday, the Ministry of Transport reported on Monday on its official website.The National Meteorological Center (NMC) added on Monday that a moderate cold snap was expected on Tuesday, causing temperatures to fall by between four and six degrees in most parts of China.The weather pattern will bring widespread rain and snow to the southern part of China from Wednesday to Friday, the NMC said.The Ministry of Railways said on its website that it has asked its local branches to be prepared for the upcoming icy weather.Meanwhile, the local authorities in big cities have been bracing for the arrival of massive numbers of travelers as the Spring Festival holiday winds down.In Shanghai, tens of thousands of public transportation workers cut their holidays short and put 27 additional bus lines on the road to meet demand as passengers began arriving in large numbers at the city's railway stations.The influx began on Saturday night, according to local newspaper Wenhui Daily.On Sunday, the pressure intensified on the Qinghai-Tibet railway, two days earlier than expected.As a result, the railway company organized additional workers to facilitate the flow of people through Xining Railway Station in Northwest China's Qinghai province.Many volunteers have also been pitching in to help keep people moving and have offered to do various jobs at stations, such as helping people buy tickets and assisting them in checking their travel schedules.Among them, Liu Chen, a student from the Guangzhou-based Zhongkai University of Agriculture and Engineering, has been helping people at Guangzhou Railway Station by carrying their bags."One day, I helped more than 70 passengers with their luggage and, after all of them got on the trains, it felt like my legs were almost paralyzed," he said.The Hohhot railway bureau in North China's Inner Mongolia autonomous region said it is expecting so many extra passengers that it has scheduled four additional trains for lines to Chongqing and Beijing.With so many people scrambling to get back from family gatherings and holidays to their jobs in China's big cities, the rush to buy tickets has been phenomenal. Tickets for trains that will leave Nanjing on Tuesday for Beijing, Guangzhou, Harbin and Changchun had virtually all gone on Monday morning, Jiangsu's Yangtse Evening Post reported.On Sunday, the fourth day of Spring Festival, the country's railways carried a total of 5.3 million travelers, which was up by 12.8 percent on the 4.7 million who rode the rails a day earlier, according to the Ministry of Railways.Another 38.6 million travelers made Spring Festival trips on Sunday on buses and ships, according to the Ministry of Transport.The traditional chunyun period, or Spring Festival travel season, runs for 40 days and is calculated in two phases: 15 days before Spring Festival Eve and 25 days after it, as stipulated by the central government.China's railways moved about 77.3 million passengers during the first 15-day period, which ran from Jan 19 to Feb 2, the Ministry of Railways reported.

BEIJING, Jan. 26 (Xinhua) -- There is some part of China that could use additional water -- the drought-hit north, even while the central government is grappling to soak up excess liquidity to contain price hikes.The dry spell has continued for months in the grain production regions in northern China, setting off concerns that it might threaten China's grain output and thus cause food price hikes, a major contributor of the country's inflation in recent months.The bad weather came and may aggravate China's battle on price hikes, including higher interest rates and reserve ratios. The government also introduced price caps and promised increases in supplies to stabilize prices.Meteorological and agricultural experts said it is still too soon to predict a decline in grain output. However, they worried that if the drought continues into the spring, grain output will fall and push up food prices.DRY SPELLWater shortages have been gripping nine provinces since October last year, including the six major wheat producing regions in China -- Shanxi, Shandong, Hebei, Henan, Anhui and Jiangsu -- which contribute more than 80 percent of the country's total wheat output.Further, rainfall in the six provinces averaged only 40.2 millimeters since October last year, down 53 percent compared with previous years, according to the National Climate Center.As of Monday, 60.39 million mu (4.02 million hectares) of crops throughout the nation were plagued by drought, according to the latest statistics from the Office of State Flood Control and Drought Relief Headquarters."There have been no rains for four months. It has been too long," said Song Qingguo, a farmer at the Xitiegang village of Qixian County in Henan, where winter wheat output accounts for almost one-fourth of the country's total."Wheat output will probably drop if such a situation continues," he worried.At present, some 15.86 million mu of wheat is exposed to drought, according to Yang Biantong, an official with Henan's water authorities.Another key wheat growing province of Shandong is facing its worst drought in 60 years, local authorities said. About 2 million hectares of land used for growing wheat, or 56 percent of the wheat-planting areas in the province, have been hit by drought, and the area is expanding, the Shandong provincial flood control and drought relief headquarters said.H Scientists say it is a result of the La Nina effect that is also responsible for the harsh winter gripping large parts of China's south, which also affected production and transportation of vegetables and other food.The Ministry of Commerce said Tuesday that Chinese farm produce prices rose for a fourth consecutive week, through Jan. 23, with the wholesale prices of 18 staple vegetables growing 12.6 percent week on week. One reason for the price hike was the freezing weather in the south, it said."The current drought in China is the second worst during the same period of time since 1961 because of the adverse weather", said Zhang Peiqun, director with the weather forecast department of the National Climate Center.The bad weather will persist in the following period of time, which means the drought in the north and the cold snap in the south will continue, Zhang said.The China Meteorological Administration forecast on Wednesday that parts of Hubei, Hunan, Anhui and Zhejiang provinces will have heavy snow or snowstorms in the coming three days. Also, icy rain will slash parts of Guizhou and Yunnan provinces.

SAN FRANCISCO, April 19 (Xinhua) -- YouTube announced Tuesday that the much-anticipated British royal wedding of Catherine Middleton and Prince William will be live streamed on the website' s live channel.Next Friday, the live stream will follow the wedding procession, marriage ceremony at Westminster Abbey and balcony kiss, said YouTube in its official blog. The official channel (www.youtube. com/theroyalchannel), will have live blog commentary of the event, and users can also upload video wishes for the couple on the site."This one is already heralded as the first of the Internet age, where for the first time in thousands of years of royal history, the moment will be captured on-line and preserved forever," said the blog post.YouTube, whose parent company is Google, will provide the technical support for the broadcast and the footage will be provided by the BBC.On April 8, YouTube launched live streaming service YouTube Live, including a home page where users can view live events and a live steaming platform on which partners with accounts could stream live content.

NICOSIA, March 8 (Xinhua) -- Cypriot geneticists have reported a non-invasive Down's Syndrome test that could possibly replace the risky amniocentesis procedure now in use.A team of researchers at the Cyprus Institute of Neurology and Genetics reported in Nature Medicine journal that the new test involves only a small quantity of blood taken from the mother's arm, which is analyzed to detect DNA differences between the mother and the fetus.Philippos Patsalis, medical director of the institute, said Tuesday the new method eliminates dangers involved with amniocentesis testing, which involves sampling amniotic fluid by inserting a hollow needle into the mother's uterus.At present, only women belonging to high risk groups, including older women, are tested for Down's Syndrome, which is the most common genetic cause of mental retardation.Patsalis, who led the study, said the new method would be made available to the medical community after clinical tests are concluded world-wide on 1,000 women within two years.