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近30年来,美国宾夕法尼亚州及东北部其他各州的软粒红皮冬小麦的产量没有多大提高,而同期许多欧洲国家都获得大幅度的增产.如英国,全国平均小麦产量从1950年的每公顷大约2,600公斤增长到1980年的5,880公斤.其增产的40%被归因于栽培管理制度的改进;其余,则是由于栽培品种的改良.高产的主要条件之一是密植齐苗.这是由精心操作栽培措施而来的——如播种量、行距、播种深度以及肥料的使用等.目前,宾夕
In the last 30 years, the yield of soft-grained red-skinned winter wheat in Pennsylvania and other northeastern states has not increased much, while many European countries have seen substantial increases over the same period. For example, in the UK, the average national wheat production has increased from around 1950 per hectare From 2,600 kg to 5,880 kg in 1980. 40% of its increase was attributed to the improvement of the cultivation management system and the rest to the improvement of the cultivars One of the major conditions for high yielding was the close planting of seedlings, Operation cultivation measures come - such as sowing, spacing, sowing depth and the use of fertilizers, etc .. Currently, Pennsylvania