【摘 要】
：
放任生长老衰栗树，虽然冠大于高，但膛内的无效叶面积大，通常约占总树冠面积的５０％～７０％，高于大冠不但不能有效地利用空间，而且，能使树体营养消耗过多，导致产量低。由于放任生长的成龄树骨干枝
【机 构】
：
河北省农科院昌黎果树所!066600
论文部分内容阅读
放任生长老衰栗树，虽然冠大于高，但膛内的无效叶面积大，通常约占总树冠面积的５０％～７０％，高于大冠不但不能有效地利用空间，而且，能使树体营养消耗过多，导致产量低。由于放任生长的成龄树骨干枝多呈掌状，相互拥挤，彼此竞争，因而，影响了膛内光照，使内膛小枝向树
Larvae old growth permit larvae, although the crown is greater than high, but the bore inside the invalid leaf area, usually accounting for about 50% to 70% of the total crown area, not only can not effectively use the space above the large crown, and can make the tree Too much nutrition, resulting in low yields. Since the larvae of all aged adult tree branches are mostly palm-shaped, crowded and competing with each other, they affect the light inside the trunk,
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