Development And Characterization Of Interspecific Hybrids And Alien Chromosome Lines From Cucumis Hystrix Chakr. Mating With C. Sativus L.

Cucumis hystrix Chakr. (HH, 2n = 24), a wild relative of the cultivated cucumber, possesses several potentially valuable disease resistance and abiotic stress tolerance traits for cucumber (C. sativus L., CC, 2n = 14) improvement, including tolerance to low irradiance and temperature, resistance to downy mildew, and resistance to fusarim wilt et al. During past years, progress has been made towards achieving gene introgression from C. hystrix following synthesis of a new fully fertile amphidiploid species C. hytivus (HHCC, 2n = 38) and the production of partially-fertile allotriploids hybrids from a mating between C. hytivus and C. sativus (HCC, 2n = 26). Nevertheless, clear evidence of the introgression of C. hystrix chromosomes or chromosome fragments into a C. sativus background is still lacking. This would be a continuation of numerous efforts to accelerate transferring the desirable traits of C. hystrix into C. sativus.In the present study, C. hystrix, several genotypic cultivated cucumbers, allotriploid and amphdiploid et al were used as core material for further investigation based on our research background. Four novel genotype interspecific hybrids F₁, two monosomic alien addition lines and ten introgression lines have been successfully developed via embryo rescue. Further cytogentic, isozyme and molecular analyses have investigated and confirmed precisely these unique germplasms from interspecific hybridization. The detailed results as following.1. Production and characterization on novel genotypic interspecific hybrids F₁ from Cucumis hystrix Chakr. mating with C. sativus L."Wild cucumber" (Cucumis hystrix, 2n = 24) is a short-day plant. Its hybridization with cultivated cucumber (C. sativus, 2n=14) is hard to be made because of their differential flowering time. In the present study, the flowering time was synchronized by...