What are the symptoms of rapeseed sterility disease?

(Agricultural Wealth Network) Also known as flower-but-no-seed disease. It is a physiological disease caused by a lack of available boron in the soil. Depending on the degree of boron deficiency, severely affected plants may shrivel and die as seedlings, while mildly affected plants may set no seed or only partial seed after flowering. In the later stages, diseased plants can be divided into three main types. First, the dwarf type: the main inflorescence and branch inflorescences of the diseased plant are markedly shortened, and the plant is distinctly stunted. The spacing between siliques is reduced. At maturity, all or most siliques on the diseased plant bear no seed. Second, the excessive-growth type: the main inflorescence of the diseased plant is markedly elongated, and the plant form is loose. A few or relatively many siliques on the diseased plant bear no seed. Third, the intermediate type: there is no obvious difference in plant height or plant form compared with normal plants. At maturity, a few or relatively many siliques on the diseased plant bear no seed.