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玉米是美国东北部奶牛业的主要能量来源,杂交种的选择是提高玉米产量、降低生产成本的关键和前提。连续5年在美国麻省大学农学实验站的典型砂壤土耕地上进行试验,结合当地气象部门提供的生育期间玉米的生长期生长度日数和降雨量,对3个早熟杂交种和3个晚熟杂交种的产量进行了年际间稳定性比较。结果表明:产量与年际间气候条件无关,无论是青贮饲料产量还是穗棒产量,晚熟品种的产量均高于早熟品种(2001年杂交种E409L)。5年平均晚熟品种的青贮饲料产量和穗棒产量分别比早熟品种高出10.9%和8.0%。相同年份品种间产量存在差异,同一品种年际间产量差异显著。低温年份,相对冷凉的生育前期和温热的生育后期不利于美国东北部玉米生产。生育期间较高的降雨量有利于青贮产量的形成。选择种植晚熟品种是该区农民提高玉米产量、降低生产成本的有效途径。只有热量多且雨量充沛的年份才有利于玉米产量潜力的挖掘。有关某种玉米基因型对当地气候适应性方面的知识,将有利于育种者选择有价值的种质资源。表6,参17。
Corn is the main source of energy for the dairy industry in northeastern United States. The choice of hybrids is the key and prerequisite for raising corn production and reducing production costs. For five consecutive years, experiments were carried out on typical sandy loam and tilled farmland at the Agricultural Experiment Station of the University of Massachusetts. Combining with the growing degree of maize growth period and rainfall during the growing period provided by the local meteorological department, three early-maturing hybrids and three late-maturing hybrids The yield stability was compared between years. The results showed that the yield was not related to the annual climatic conditions. The yield of late maturing varieties was higher than that of early maturing varieties (2001 hybrids E409L), no matter silage yield or panicle yield. The silage yield and ear stick yield of 5-year-average late-maturing cultivars were 10.9% and 8.0% higher than the precocious varieties respectively. There was a difference in yield between varieties of the same year, with significant difference in annual yield of the same variety. In low-temperature years, relatively cool pre-emergence and warm post-growth stages are not conducive to maize production in the northeastern United States. The higher rainfall during the growth period is conducive to the formation of silage production. The choice of cultivating late-maturing varieties is an effective way for farmers in this area to increase corn production and reduce production costs. Only the years with more calories and more rainfall are conducive to the potential of corn production. Knowledge of the adaptability of a maize genotype to local climates will help breeders choose valuable germplasm resources. Table 6, Senate 17.