一、寒地稻作上的一个重要课题寒地稻作中存在的首要课题,应为冷害问题。各地因成熟不良而招致减产的田块,历年都占有一定比重,如遇低温年份则减产的比率更大。从根本上解决冷害的措施,应是选育早熟而耐寒的品种,但矛盾的是:品种的早熟性和高产性往往是很难统一的。这从唯物的观点看来亦很容易理解,在一般情况下,光合作用期较长的品种,其对光能 First, an important issue on the rice in cold areas Cold paddy rice in the primary issue, should be chilling injury. The plots that have been cut down due to poor maturity have taken a certain share over the years, with a larger rate of cut in the case of low-temperature years. The fundamental solution to the chilling injury should be to breed precocious and cold-tolerant varieties, but the contradiction is that the precocious varieties and high yield are often difficult to unify. It is also easy to understand from a materialistic point of view. In general, varieties with a longer photosynthesis period have different effects on light energy