主要梨属砧木枝条导管分子结构比较分析

Comparative Analysis on Vessel Elements in Branch of Pear Rootstocks(Pyrusspp.)

为探索梨树砧木的矮生机制,以矮生型梨砧木‘PY-9’、‘BA-29’、‘OHF-87’、＂东7-7＂、＂中矮Ⅱ号＂、＂FOX11＂等为试材,以普通型梨砧木杜梨（Pyrus betulifolia）、豆梨（P.calleryana）、砂梨（P.pyrifolia）、秋子梨（P.ussuriensis）、木梨（P.xerophila）、川梨（P.pashia）、褐梨（P.phaeocarpa）、杏叶梨（P.armeniacaefolia）、柳叶梨（P.salicfolia）等为对照,采用组织离析、显微照相与生物学统计方法,对1年生枝条导管分子的形态和大小进行了观察。结果表明：普通型和矮生型梨砧木的导管分子形态多为圆柱形,均属于孔纹导管;其矮生型导管分子的穿孔板类型、有尾情况、端壁倾斜状况、端尾长度与普通型无明显差异;矮生型导管分子平均长度在275.1-300.8μm,平均直径在26.1-29.9μm;普通型梨砧木枝条导管分子平均长度在331.6-399.3μm,平均直径在31.2-36.0μm;矮生型梨砧木导管分子长度与直径显著小于普通型梨砧木。以上结果表明,矮生型梨砧木表现出小导管性,这可能是矮生型梨砧木致矮的细胞学原因之一。

In order to explore the dwarfing mechanism in pear trees,taking standard tree（P.betulifolia,P.calleryana,P.pyrifolia,P.ussuriensis,P.xerophila,P.pashia,P.phaeocarpa,P.armeniacaefolia,and P.salicfolia）as control,the shape and size of vessel elements in annual branches of dwarf tree（‘PY-9＇,‘BA-29＇,‘OHF-87＇,‘E7-7＇,‘ZhongaiⅡ＇and ‘FOX11＇）were examined using tissue segregation procedure,micrograph and biometric statistical method.The results showed that there were various types of vessels in different pear rootstocks.The characters of vessel elements,pitting pattern,types of perforation plates,frequency of different tail types of vessel element and frequency of different end wall tilt types of vessel element in stem of dwarf tree were basically consistent with those of standard trees,but the length and width of vessel element in dwarf trees were significantly smaller than those of standard trees.The mean length at 331.6-399.3μm,average width in 31.2-36.0μm for dwarf type,the mean length in those standard trees at 275.1-300.8μm and average width in 26.1-29.9μm.The vessel element in dwarf pear rootstocks showed smaller vessel elements,which might be the important reason for dwarfing phenomenon in dwarf pear rootstocks.