我国大豆栽培面积仅次于美国、巴西居世界第三位,但单产则低于世界平均水平,如1986年我国太豆公顷产量为1402公斤,而世界平均为1841公斤。黑龙江省是我国大豆主要产区,1987年大豆栽培面积占全国21.3%,公顷产量为1605公斤,低于美国和巴西。为实现1990年全国大豆出口20亿公斤,还需要大力提高单产。草害是影响大豆单产的 China’s soybean cultivation area is second only to the United States, Brazil ranks third in the world, but the yield is below the world average. For example, in 1986 China’s soybean yield was 1402 kilograms, while the world average was 1,841 kilograms. Heilongjiang Province is the main soybean producing area in China. In 1987, the soybean cultivation area accounted for 21.3% of the national total, and the output of hectare was 1605 kg, lower than that of the United States and Brazil. In order to realize 2 billion kilograms of national soybean exports in 1990, we also need to greatly increase yields. Grass damage is affecting soybean yields