Study On The SSR Molecular Markers Of The Indian Squash (Cucurbita Maxima)

Pumpkin germplasm resources are very rich,wide-range in application and widely grown in the world,which have different climatic adaptations and are widely distributed in agricultural regions worldwide.At present,most of the pumpkin grown in China is long vine,and there are fewer dwarf varieties with no vine or short vine.Pumpkin's no vine varieties need less space for cultivation and easier to manage.They are suitable for dense planting and have great advantages in production.No-vine plants in Cucurbita moschata have some features that make them valuable.This makes them value in pumpkin breeding.Dwarf type is one of the most important agronomic traits,and the dwarf genes have been the focus of agricultural research.Study of dwarf genes in Cucurbits is still in the initial stage,and location and mechanism of dwarf type in Cucurbits is still less reported on.There were five cultivated species:Cucurbita pepo?Cucurbita moschata?Cucurbita maxima?Cucurbita mixta and Cucurbita ficifolio.Only Cucurbita pepo?Cucurbita moschata possess the bush trait.This paper summarized the advantages in no-vine plants of Cucurbita,and the research progress on bush type.To investigate the dwarf traits in Cucurbita application and development trend in crop breeding.In order to understand the genetic characteristics and linkage with molecular markers of bush type genes.It will lay a theoretical foundation for studying the genetic mechanism of bush type and better utilizing its heterosis.In this study,two high-generation inbred Cucurbita maxima long vine 6820 as male parent,bush type 1820 as female,hybridization then a single F1 was produce to F2population.Combine SSR markers and BSA with the early gene positioning of pumpkin bush type character.The results were as follows:500 pairs of SSR primers were screened by SDS-PAGE,only 362 SSR primer screening in tested parents and 35 showed polymorphism between long vine samples and bush type samples.The F2 population consisted of 189 Cucurbita maxima individuals.Combine SSR markers and BSA,the 35 polymorphism SSR primers were then used to analyza the F₂population between two long vine 6820 and bush type 1820 DNA pool of Cucurbita maxima.The selected markers was tasted with individual of F₂ population,it was found that some primer pairs were not steady and didn't show polymorphism.Thus,only 6 pairs of polymorphism SSR primers were used for further analysis.After analyzing the statistic correlation between the SSR markers and the bush trait,six SSR primers termed showed significant correlation.