前言在美国利用的梨树砧木中,只有榅桲属的无性系砧木EM榅桲A和C,Provence榅桲C或BA29及西洋梨的OH×F51能使梨品种产生半矮化的树体大小。在这些砧木上的树体大小,对于由地面手工操作或密植园中保持树体的控制可能显得太大。同时榅桲砧也有其弱点,与大多数梨品种亲和力差,易生根蘖,固地性不好,不抗火疫病。不抗寒。但嫁接在榅桲砧上的梨品种结果早,产量高,抗梨的衰退病。嫁接在OH×F51砧木上的梨树在加拿大表 Foreword Among the pear tree rootstocks used in the United States, only the clones EM 榅 桲 A and C of the genus Culms, Provence 榅 桲 C or BA29 and the OH × F51 of the pear can produce semi-dwarf tree size . The size of the tree on these rootstocks may be too large for the tree to be held by the ground by hand or in a close plantation. At the same time 榅 桲 anvil also has its weaknesses, most pear varieties with poor affinity, easy to root tillers, solidity is not good, not fire-resistant blight. Not cold-resistant. However, pear varieties grafted on the 榅 桲 anvil result early, high yield, anti-pear decline. Pear trees grafted onto OH × F51 rootstocks are on the Canadian Table