造成新植杨树林发病、死亡的原因有以下几个方面：一是长期单一培育杨树等深根系品种，使苗圃土壤肥力下降，土壤病原微生物积累，病害易发生。二是育苗时，没有选择良种壮苗作为种条，而是使用留床苗、瘦弱苗、平.
山东十大凡人善举颁奖典礼在尼山圣源书院举行_孔孟之乡
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速生杨栽植抚育存在问题及对策-实用技术-农博数据中心
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杨树新品种介绍：北抗杨1号、创新杨1号和欧黑12号-实用技术-农博数据中心
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浅谈杨树造林技术措施及有害生物的防治-实用技术-农博数据中心
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