关键词: 梨, 梨, 杂交后代, 童期, 童程

Abstract:

In order to respond the climate change, and investigate the effect of Maize planting in different sowing time as a result of climate change, we use the test method of sowing in different time, research the optimum sowing maize in Eastern Gansu Province. The analysis about the experiment data of Maize sowing by stages show us: different sowing time’s growth speed change of maize mainly displayed in seedling stage, it grew more slowly which was seeded earlier, and time interval between two developmental phases was longer; it grew faster which was seeded later, and time interval between two developmental phases was shorter. Dry matters’ increment of every developmental phase in different sowing time weren’t same, this difference mainly displayed in reproductive stage, increment of dry matters were the highest in the second and the third sowing stage, and in vegetative growth period the difference of dry matters’ increment was unconspicuous. Soil water storage’s effect to yield was not the same in different sowing time and at different level of soil, no matter superficial layer or deep layer, soil water storage present positive effect from seeding stage to elongation stage, and present negative effect from tasseling stage to maturation stage, and especially had a major influence to yield at superficial layer. Meanwhile, result for analysis showed that the third sowing stage was the most optimum sowing stage, in growth period of this stage, light, temperature and water were matched well, dry matters had a good increment and yield. According to these conclusions, climatic change made the optimum sowing time of maize in Longdong region pulled off.