甘蔗×斑茅远缘杂种的鉴别

本试验采用染色体Giemsa—C带分带和过氧化物酶同工酶电泳频谱分析方法对野生种斑茅(Saccharum arundinaceum Retz.)与甘蔗的远缘杂交后代进行鉴别分析。结果表明,F_1代崖城73/07(2n=68)、崖城75/283(2n=68)染色体数组成为n+n型,染色体带型和同工酶谱均表现为父、母本综合型,崖城57/25(2n=110)、崖城73/512(2n=110)则分别与其母本相似。据此认为,4个待定材料中,仅前二者是真实的斑茅远缘杂交后代。 根据上述结果分析了斑茅对甘蔗育种尚无实质性贡献的原因,认为该野生种之育种性能与其染色体带型有关。最后,讨论了同工酶分析及染色体分带作为杂种鉴别方法的意义及其局限性。

IDENTIFICATION OF THE HYBRIDS BETWEEN SACCHARUM ARUNDINACEUM RETZ. AND SUGARCANE VARIETIES

By means of chromosome Giemsa-C banding and polyacrylamide gel electrophoresis of pcroxidase isozymes, four clones derived from Saccharum arundinaceum Retz. and their parents were analysed to identify the hybrids. The main results were as follow,1 . Among 60 chromosomes of S.arundinaceum,56 were characterized by the present of telomerlc bands, while only 2 or 4 of such chromosomes were detected in one cell of the sugarcane varieties. The differences of C-banding pattern between the male and female parents were significant.2. Clones Ya Cheng 73/07 and Ya Cheng 75/283 were true hybrids as they showed intermediate characters between the two parents both in chromosome C-banding pattern and peroxidase zymogrom. The other two, Ya Cheng 57/25 and Ya Cheng 73/512 were obviously closed to their female parents respectively.The value and behaviour of S. arundinaceum in sugarcane breeding was estimated onthe basis of chromosome C-banding patterns, and the advantage and limit of the threemethods used in identificating of hybrids were discussed.