论文部分内容阅读
一、制种田必须能灌能排掖单4号夏播制种整个生育时期要经历干旱高温、雨涝多湿的6、7、8、9月。而影响制种产量的灾害性气候将时有出现。6月上、中两旬常年多以晴朗干旱天气为主,此时正值夏制播种佳期。由于空气干燥,土壤墒情较差,加上自交系苗期耐旱能力较弱,对一播全苗极为不利。往往形成播种5000穴,成苗不足3000株的被动局面。6月下旬至7月上中旬这30天中,常年多以连阴雨涝、高温高湿天气为主,此期正是父母本营养生长与生殖生长两旺时期。由于长期阴雨,地下水位增高,田间湿度加大,土壤板结严重,根系发育不良,病害大量发生,植株生长瘦弱,搭不起丰产苗架。如遇多雨大雨年份,田间积水,植株受淹受渍,僵苗、大小苗现象十分严重,甚至导致青枯死苗。
First, the system of farming must be able to irrigation can be arranged to secrete a single No. 4 Summer sowing throughout the reproductive period to experience drought, high temperature, rain and wet more wet 6, 7, 8, September. The disastrous climate that affects the production of seed will emerge from time to time. In June, mid-summer and mid-summer are mostly dry and sunny weather, at which time the summer planting season begins. Due to air drying, poor soil moisture, coupled with weaker drought tolerance in seedling stage, is extremely unfavorable to the whole plant seedlings. Often formed a planting 5000 points, seedlings less than 3000 passive situation. From late June to mid July this 30 days, perennial rain and waterlogging, high temperature and humidity weather, this period is the parental vegetative and reproductive growth boom. Due to prolonged overcast and rainy days, groundwater level increased, field humidity increased, soil compaction was serious, root system was underdeveloped, disease occurred in large numbers, and plant growth was weak. In case of rain and rainy years, field water, plants flooded stains, stiff seedlings, seedling size is very serious, and even lead to dead seedlings.