SRAP Molecular Marker Linked To Gl Gene In Cucumber

Trichomes is an kind of appendage for many plants on the earth, generating from the epidermal cells. It is divided into single-cell or multi-cell, some of them have superficial glands that can produce some secrete substances or some secondary metabolites, and some of trichomes are non-gland, the same plant can produce different types of trichomes. The trichomes of Arabidopsis, which is a model plant because of its simple structure and easy to observe the merits of research, have become a model for the system building of trichomes cell.The course of epidermal cells into trichomes cells of Arabidopsis involved in the process in which the complex constructed by the transcription factor of three components is the active regulation and the other inhibitatis negative control. The first is GLABRA1 (GL1), it is a two contain DNA-binding domain repeat MYB transcription factor, belonging to the R2R3 types of MYB family, and the second is TRANSPARENT TESTA GLABRA1 (TTG1), which encodes a WD40 repeat of the Protein, but also affects several other metabolic pathway that the two transcription factors and GLABRA3 (GL3) for each other and form a complex, GL3 mutation of the performance of the plant to reduce the hair, it is a bHLH family of transcription factors.Cucumber is one of the world's top 10 major vegetable crops, while is also one of the important species in China. The fruit of cucumber is the most important part of economic traits. The stems, leaves, tendrils, the calyx, the surface of the cucumber are covered by short bristles, fruits have thorns. Most of ovary are with the surface of the tumor-like processes, and the tumor are barbed. But some varieties of fruit on the fruit do not have tumor. Through histological observation, it was found that in cucumber both leaves and fruit are the same on thorn morphology of the fruit, are multi-cell-free form of skin glands.Taking the two types of cucumbers, trichomes (GlGl) wild type S06 and mutant type glabrous (glgl), as the parents, and their future generations F1, F2 for genetic analysis. The results showed that: in the F1 generation, the performance of all the fruits are the trichomes, so the trichome trait is dominant; in the F2 generation, trichomes has appeared glabrous separated. The ratio of detection x2 is the Mendelian ratio of 3:1 without significant difference. Through the genetic analysis of cucumbers, whether the cucumber has trichomes or not is determined by a pair of nuclear gene Gl/gl, and the trait of trichomes (Gl) is dominant to the glabrous(gl). By combining bulked segregant analysis (BSA) and the sequence-related amplified polymorphism (SRAP) technology, and two dominant markers ME6EM5 and ME23OD15 were detected, both of them are in the same side of GL loci. They are linked to the Gl gene at the distance of 3.6cM and 12.9cM respectively. Moreover, 1825 pairs of SSR primers have been used to screen the three parents S94, S52 and S06 respectively for their polymorphism. S94 belongs to the North China type, diclinous flower, unlimited growth, weak growth potential collateral; S52 belongs to the South China type, the performance in the fields for the strong male, less collateral; S06 belongs to the European type, all-female, unlimited growth, collateral strong growth potential. The results show that: between S94 and S06, 516 pairs of primers appeared polymorphism, the ratio is 28.27%; between S52 and S06, 554 pairs of primers appeared polymorphism, the ratio is 30.35%; between S94 and S52, 426 pairs of primers appeared polymorphism, the ratio is 23.34%.