Rice needs a good water supply to grow. Water is wasted daily all over the world and estimates suggest that most Asian countries will have severe water problems by 2025. It takes 5000 litres of water to grow a kilo of rice, yet many rice growing areas in Asia and Africa are drought-prone. Scientists need to develop varieties of rice that can withstand sudden heavy rains and complete with weeds.
Worryingly, rice production is affected by global climate changes. Global warming is caused by toxic gas emissions in developed countries. The rise in global temperature cuts rice-growing time,and ultra violet light radiation from the sun reduces tolerance to disease. Methane gas, one of the culprits of global warming, is, ironically, a by-product of wet lowland rice cultivation. Methane-producing bacteria thrive in wet rice fields and the plants themselves send the gas into atmosphere. Water management could reduce methane emissions, but practical methods that do not reduce rice yields still have to be found.