A Chinese scientist has been named one of the top five crop researchers who could change the world in the face of soaring food prices and intensifying water shortages. Hong Kong Baptist University's head of biology, Zhang Jianhua, was featured by the prestigious scientific journal Nature last week as one of the 'Five Crop Researchers Who Could Change the World'. The plant physiologist was portrayed as the only scientist out of the five with the potential to have an immediate impact. The recognition was for his research on minimising water used on irrigation by manipulating plant hormones. This could almost halve water consumption in north and northwestern China where rainfall is scarce. 'I hope my research will ultimately lead to the betterment of mankind by enhancing crop production and alleviating world hunger,' Professor Zhang said. As a young boy, he endured much hardship during the mainland's great famine and Cultural Revolution. He worked as a peasant in the fields and remembers the struggle to fill his stomach with rice shells and tree leaves. 'I was very pessimistic back then and thought I'd end up as a peasant forever,' Professor Zhang said. His hard work paid off when the government sent him to Britain's Lancaster University to carry out research. Professor Zhang discovered that plants could sense when soil was becoming dry and sent a chemical signal from their roots to their leaves. He said plants produced a stress hormone to reduce water consumption during droughts. Manipulating the response of crops by artificially drying parts of their roots meant farmers could then use less water for irrigation. After arriving Hong Kong in 1991, Professor Zhang started to apply the knowledge discovered from laboratories on the crop fields in the mainland. Now 52, Professor Zhang is expanding the use of the deficit irrigation system on wheat by leaving it in dry soil and irrigating infrequently. 'With other water-saving techniques like covering the soil with plastic films and drip irrigation, we are now only using half the water that we used 10 years ago,' he said. Professor Zhang said water shortages in north and northwestern China had been a major problem. About half of the 900 million peasants could use up to 80 per cent of the water in the area for irrigation. 'We have to cut down the water use for crops, otherwise natural vegetation will disappear. It's an ecological disaster.' With farmers now receiving subsidies for irrigation schemes, Professor Zhang hopes to ease water shortages and start giving more back to the ecosystem within three to five years.