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棉花一县一种、一区一种是根据当地的自然特点,在一个县范围内实行品种区域规划。在这个基础上,逐步实现两圃制提纯复壮,普及棉花原种一代、二代,这是防止混杂退化、发挥良种增产潜力的重要方法。而在不同的自然条件下,选用适应当地种植的棉花生态类型,也是增产的重要措施之一。如运城地区平川无霜期为220—240天,适宜种植中、早熟棉花品种;而沿山地区无霜期仅150—130天,适宜种植特早熟棉花品种,既使在中、早熟棉区,充分利用其自然资源,复播特早熟棉花
Cotton one county, a district one is based on the local natural characteristics, in a county-wide implementation of regional planning. On this basis, it is an important method to prevent and control degeneration and increase the potential for yield increase by gradually realizing the purification and rejuvenation of the two nurseries and popularizing the first generation and the second generation of cotton raw materials. In different natural conditions, the selection of cotton varieties adapted to the local ecological types, but also one of the important measures to increase production. Such as Yuncheng Hirakawa frost-free period of 220-240 days, suitable for planting medium and precocious varieties of cotton; frost-free period is only 150-130 days along the mountainous areas, suitable for the planting of precocious cotton varieties, even in the precocious cotton area, take full advantage of its natural Resources, complex pre-special cotton