By Andras Gergely BUDAPEST, Sept 20 (Reuters) - Biofuel production and burning agricultural by-products in power plants contributed to Hungary's severe drought this year, an academic expert said on Thursday. Drought slashed Hungary's maize crop by half this year but dry weather would have less impact on crops if farmers left the plants' stalks and straw on the fields as protection from the sun and evaporation, instead of selling it as biomass. "There is plenty of biomass out there to burn and lots of fallow land to grow energy crops," Szent Istvan University professor Marta Birkas told a farming conference. "I caution everyone not to sell straw and stalks to power plants," she said. "The soil needs it as a protection from drought." Biofuel makers turn grains and oil seeds into gasoline and many burn farm byproducts to meet the often high energy needs of their plants for processes like fermentation. Biofuels are touted as a way to reduce the emission of greenhouse gases which contribute to global warming, but Birkas said biofuel production was now adding to the problems caused by extreme weather which many blame on climate change. Wrong farming methods, especially careless ploughing, also reduces the soil's ability to store water efficiently, she said. Ministry officials said Hungary would invest heavily in farm machinery and irrigation to address these problems as drought was becoming more frequent, hitting the major grain growing country for the fourth time in 10 years. "Soil dryness has several causes, both lack of precipitation and wrong agricultural techniques," Agriculture Minister Jozsef Graf told Reuters. Hungary needs to raise its irrigated area by at least 100,000 ha from about 80,000 hay, another official said. This year's drought is expected to cut the maize crop by half to 4 million tonnes and Hungary has started buying back grain left in European Union stores from previous bumper seasons to sell to animal breeders short of feed.
