Comparative Analysis of Karyotypes among Octoploid Trititrigia and Its Original Parents

摘要

This paper uses T.aestivum, elytrigia intermedium and their distant hybrid progeny octoploid trititrigia as the test materials, and makes comparative analysis of the chromosome karyotypes of the three species with which have phylogenetic relationships by chromosome tablet method. The results show that: T.aestivum yannongl5 has the karyotype formula as 2n=6x=42=30m+ 12sm (4SAT), and its karyotype is 2A; Elytrigia intermedium has the karyotype formula as 2n=6x=42= 16m+20sm (4SAT)+6st, and its karyotype is 3B; Their distant hybrid progeny octoploid trititrigia shannongTE0521 has the karyotype formula as 2n=8x=56= 36m (2SAT)+20sm (2SAT), and its karyotype is 2B. According to the karyotype evolutionary theory by Stebbins and the nuclear-based cladistic method, as well as analysis of the 4 traits of the karyotype, the results shows that the evolution of the octoploid trititrigia is in the middle of its two original parents. It is in this paper gives the first report of the karyotype of octoploid rititrigia, and makes preliminary study on the chromosomes and genetic evolution relationships of octoploid trititrigia and its original parents.