加拿大引进的二倍体燕麦种质的核型鉴定

采用常规压片法对砂燕麦、西班牙燕麦和短燕麦3个二倍体燕麦种进行了核型研究。结果表明:砂燕麦染色体核型公式为2n=2x=14=10m+4sm(2SAT),具近中部和中部着丝点染色体,第4对染色体组的短臂上有1对随体,核不对称系数为68.17%;西班牙燕麦染色体核型公式为2n=2x=14=10m+4sm(2SAT),具近中部和中部着丝点染色体,第7对染色体短臂上有1对随体,核不对称系数为59.31%;短燕麦染色体核型公式为2n=2x=14=6m+4sm+4st(2SAT),具近端部、近中部和中部着丝点染色体,第6对染色体组的短臂上有1对随体,核不对称系数为63.91%。虽然3个燕麦种的核型均为2A,但它们的染色体形态有明显不同,比较认为砂燕麦相对进化,短燕麦次之,西班牙燕麦较原始。本研究对燕麦种质资源的核型分析及进化地位研究具有参考价值。

Karyotype Analysis of Diploid Oat Germplasm Introduced from Canada

The chromosome karyotype of three diploid oat species was studied with squash method. The results showed that the karyotype formula of Avena strigosa was 2n=2x=14=10m+4sm(2SAT), with metacentric and submetacentric chromosomes,1 pair of satellites on the short arm of the 4th chromosome and 68.17% for the asymmetry index; that of Avena hispanica, was 2n=2x=14=10m+4sm(2SAT), with metacentric and submetacentric chromosomes, 1 pair of satellites on the short arm of the 7th chromosome and 59.31% for the asymmetry index ;and that of Avena brevis was 2n=2x=14=6m+4sm+4st(2SAT), with acrocentric,metacentric and submetacentric chromosomes, 1 pair of satellites on the short arm of the 6th chromosome and 63.91% for the asymmetry index . Although the karyotypes of all three species were 2A type, there was obvious variation in the morphologies of karyotypes of three species, which comparatively indicated that the karyotype of Avena strigosa was more advanced in evolution, followed by Avena brevis and the karyotype of Avena hispanica was more original. This study will be a useful reference for the karyotype analysis and evolutionary analysis of oat germplasm resources.