Using The Haploid Induction Technology Zucchini WMV Resistant Germplasm Innovation

Haploid culture techniques can be used to quickly homozygous breeding intermediate material, to obtain the genetic stability of inbred lines, save breeding time and workload, improve the breeding speed and efficiency. Five squash genotypes(XH01, XH02, XH03, XH04 and XH05) were used as test materials in this study, and the unfertilized ovary biopsy or ovule independently were cultured in different mediums in order to set up efficient squash haploid induction system. The results show that the rate different for genotypes vary, the highest rate of materials for XH05, the second was XH04, and the west were XH01 and XH02. Different culture medium on the embroil induction effect difference to be markedly, the type of additives the embroil induction rate, adding casein hydrolysate and induced the highest rate of yeast extract medium. The concentration of the additives is a significant effect on embroil induction rate, add 100 mg/L casein hydrolysate medium embroil induction the highest form of regeneration plant ability, inducing rate can reach 66.7%, the rate is not high but the haploid induction rate is only 2.1%.Stomatal guard cells counting method and flow cytometry instrument analysis method to carry on the regeneration plant ploidy identification, and by using the specific EST- SSR markers of haploid regeneration plant or natural double haploid plants quickly identify analyzed, received a total of 15 strains of haploid plants. Experiment by plant morphology observation times sex identification of the regeneration plant analysis.Watermelon Mosaic virus(WMV) is one of the main problems of hazard cucurbitaceae crops. For the virus is still no effective prevention and control measures. Breeding resistant varieties is an effective way to squash the production safety, but now squash WMV disease-resistant varieties is less. Squash molecular marker assisted breeding research started late, the available tags exist are few in number. This study results show that the Squash WMV virus resistance is controlled by the dominant single gene. Using 574 pairs of SSR and EST SSR molecular markers will be located in the disease-resistant genes on a small group of chain, among them, the tag SSRM137 recently, genetic distance and WMV resistance gene, the genetic distance of 1.37 cM.Backcross commercial technologies are used to get the Squash WMV virus resistance of homozygous plant cycle is long, but with the haploid induction technology against WMV regeneration plant genetic purification, can greatly shorten the breeding period, laid the foundation for squash disease-resistant germplasm innovation.