SRAP Markers Linked To The Green Skin Trait Of Cucumber

The method of BSA combining SRAP was used to detect the molecular markers linked to the green skin color of Cucumber in the F2 individuals from the cross of WD3×B-2-2. The results are as follows:The 123 F2 individuals were produced from a cross of WD3×B-2-2. The fruits of Cucumber were classified into two categories according to the chlorophyll content of fruit skin: the green skin individuals which chlorophyll content was between 0.07 ~ 0.08 mg ? kg-1; the white skin individuals which cholrophyll content was under 0.005 mg ? kg-1. There were 94 green skin individuals and 29 white skin individuals in the F2 population. The ratio of the green skin plants and white skin plants is close to 3:1.The DNA of Cucumber was extracted from the young leaves through the method of improved CTAB. It showed that the DNA extracted by this way was integrity and had a higher quality through the detection of 1% agarose gel electrophoresis.The DNA pool of green skin individuals and white skin individuals were constructed respectively according to the DNA content. The DNA of two gene pools was amplified with a total of 380 SRAP primers initially, of which 2 showed polymorphism between two gene pools. The result of individual amplification showed that only two specific fragments ( ME9EM1-309 and ME8EM14-425 respectively) deriving from 2 primers combination The coincidence rate of the color on F2 and the bands is 93.4% and 96%, respectively. It showed that the genetic distance from ME9EM1-309 and ME8EM14-425 to the green skin gene was 6cM and 8.3cM through analysis of JOINMAP 3.0.The two specific fragments were reclaimed from electrophoresis gel and cloned in T-easy vector. It showed that the size of inserted bands was same as that of the target fragments, and the fragment of ME9EM1-309 is 309 bp, ME8EM14-425 is 425 bp. The results of Blast showed that there were no similar squence with thest two squence in the GeneBank, it was believed that thest two squences might be new ones which were linked to the green skin trait.This study used the method of molecular biology SRAP molecular markers, study the color of green cucumber peel traits, and provide the method to select and identification a new variety of cucumber germplasm resources in the early time and provide a theoretical basis.