近几年,在向日葵产区,随着单产的降低,经济效益小,种植面积和总产量也逐年减少。据调查,主要原因是向日葵的成粒率下降,空壳和秕粒率增加,尤其是花盘中间部分更为严重,一般情况下空秕粒达30—40%。空壳的原因主要是授不上粉造成的,秕粒主要是营养不足和干旱少雨造成的。为了提高向日葵的结实率,应采取以下措 In recent years, in the area where sunflower is produced, as the yield decreases, the economic benefits are small, and the acreage and total output also decrease year by year. According to the survey, the main reason is the decrease of the sunflower granulation rate, the increase of the empty shell and the fermented grains, especially the middle part of the flower disc. In general, the empty granule reaches 30-40%. The reason for the shell is mainly caused by the powder is not given, the grain is mainly caused by lack of nutrition and drought. In order to improve the seed setting rate of sunflower, the following measures should be taken