普通小麦与冰草间杂种的细胞遗传学及其自交可育性

Cytogenetics and Self -fertility of Hybrids Between Triticum aestivum L. and Agropyron cristatum(L.)Gaertn

为了进一步研究冰草属（ＡｇｒｏｐｙｒｏｎＧａｅｒｔｎ．）的Ｐ染色体组与小麦染色体组间的遗传关系和评价Ｐ染色体组在属间杂种自交可育性上的遗传效应，获得了普通小麦品种Ｆｕｋｕｈｏ（Ｔｒｉｔｉｃｕｍａｅｓｔｉｖｕｍｃｖ．Ｆｕｋｕｈｏ，２ｎ＝４２；ＡＡＢＢＤＤ）与３个不同来源的四倍体冰草（Ａ．ｃｒｉｓｔａｔｕｍ〈Ｌ．〉Ｇａｅｒｔｎ．，２ｎ＝２８；ＰＰＰＰ）间的杂种（２ｎ＝３５；ＡＢＤＰＰ）。结果表明：（１）不同组合的杂种间在遗传基础上差异明显，同一组合不同杂种间亦有差异；（２）冰草Ｚ５５９可能不存在抑制小麦Ｐｈ基因效应的遗传系统，但与小麦染色体组间可能存在部分同源性；（３）生长正常的Ｆｕｋｕｈｏ×冰草Ｚ５５９的杂种具部分自交可育性和明显的异花授粉结实特性，而且这些可育性很可能是由Ｐ染色体组中控制染色体在减数分裂后期分离的特殊遗传因子决定的；（４）冰草属的多倍体并非严格的同源多倍体。本实验还证实了通过幼穗培养产生再生植株，可以使属间杂种的育性显著提高。

To further investigate genomic relationships between Agropyron and Triticum,and to evaluate genetic effects of the P genome on self-fertility in intergeneric hybrids, the hybrids of T. aestivum cv. Fukuho(2n=6x=42; AABBDD)with threeaccessions of tetraploid A. cristatum(L.)Gaertn.(2n=4x=28; PPPP)were obtained. Results indicated that:(1) Genetic basis differred markedly among hybrids from the various combinations, so did relatively among hybrids in the same combination;(2)A.cristatum Z559 used in this experiment could not contain a genetic system to switch off Ph suppressor of wheat, but homoeology may exist between theP genome and the wheat genomes;(3) The hybrids growing normally of Fukuho ×A. cristatum Z559 were partially self-fertile, with a character of crossing reproduction. The fertility was possibly determined by a special genetic factor controllingchromosome segregation at meiotic anaphase in the P genome;(4)The type of polyploid in Agropyron was not strictly autoploid. It was further verified that fertility of the intergeneric hybrids could be increased greatly through plants regeneratedfrom immature in florescence cultures.Received June 24,1993. Mr. Yang Xinming also takes part in this research work