Karyotype And ISSR Analysis On 6 Color Potato Varieties

To know the degree of genetic difference in cytogenetics and DNA lever among 6 color potato varieties which are Desiree, Russet-01, Heimeiren, Qingshu168, Sepihong and Shuixihong, and provide evidence for color potato germplasm evaluation and cross breeding, the chromosome karyotype and polymorphism among the tested plants were analyzed based on conventional chromosome slice production method and ISSR molecular marker. The results showed that:①The RTC chromosome number of 6 color potato varieties were 48, which belong to the tetraploid (2n=4x=48).②The karyotype formula of Desiree and Heimeiren were 2n=4x=48=36m+12sm, the karyotype formula of Russet-01was 2n=4x=48=32m+16sm, the karyotype formula of Qingshu168 was 2n=4x=48=24m+24sm, the karyotype formula of Sepihong was 2n=4x=48=44m+4sm, and the karyotype formula of Shuixihong was 2n=4x=48 =40m+8sm.③The karyotype of Desiree, Heimeiren and Sepihong were 1B, the karyotype of Russet-01, Qingshu168, and Shuixihong were 2B.④151 bands of ISSR markers were amplified in the genomic DNA of 6 color potato varieties with 12 suitable primers, and 136 bands were polymorphic, and the percentage of polymorphism bands reached 88.2%, the genetic variation was abundant, so ISSR fingerprinting could be the molecular evidence to distinguish 6 tested plants.⑤The genetic distance (GD) of 6 color potato varieties were ranged from 0.4803 to 0.7073, using the GD value of 0.57 as threshold, 6 tested plants could be clustered into 3 groups: the first group including Desiree and Heimeiren, the second groups including Russet-01, Sepihong and Shuixihong, and the third groups only including Qingshu168.