据国外《向日葵》1984年第2期介绍,大田作物,其中包括向日葵,若要获得高额稳定的收成,只有正确实行有充分科学论据的轮作才有可能。其重要程度由下述例子可以看出。20年前,曾拨给全苏油料作物所一片生荒地。当时,每一平方米播种地上有270—290株杂草。在轮作开垦的头几年,冬小麦的产量为 According to foreign “sunflower” 1984 the second period introduction, field crops, including sunflowers, to obtain a high and stable yield, only the correct implementation of a rotation with adequate scientific arguments is possible. Its importance can be seen by the following example. Twenty years ago, it allocated a wasteland to the entire Soviet oil crop. At that time, 270-290 weeds were planted on each square meter of land. In the first few years of crop rotation, winter wheat production was