Investigation Of Crops Germplasm Resources With Drought-resistant And Salt-tolerant Traits In Coastal Areas

Coastal areas of China possess a variety of climate types, geographicenvironment and complex ecosystem, which play a large role shaping the complexbiodiversity of the crop resources, especially the drought-resistant and the salt-tolerantgermplasm resources. Investigation, collection and using of these excellent resourcesare effective ways against extreme natural disasters such as drought and saline.In this study, the germplasm resources in125coastal counties of11coastalprovinces in China coastal areas were investigated and collected.And some resourceswere selected to evaluate their salt tolerance to explore salt-tolerant germplasmresources in coastal areas.At the same time, the genetic diversity of1137accessionsof wild soybean, collected from the coastal areas of Liaoning, Shandong and Hebeiprovinces, which were evaluated by using29SSR molecular markers. The mainresults are as follows:1. The cultivated land area in China coastal areas became smaller and smaller. Thelocal crop germplasm resources will be endangered for economic developmentand the single crop species large area planting.2. Total4635accessions of crop germplasm were collected from China coastal area,including3538local varieties,599wild resources,365breeding varieties and133other types. Among them,1766accessions were conserved in the nationalrepository.3. Total1030accessions of crop germplasm were evaluated for the salt tolerance.And97,343and56resources with salt tolerance at the germination stage,seedling stage and the whole growing season were found.The salt tolerance ofcrops at the germination stage and seedling stage were not associated but thephysiological responses had a certain correlation with phenotypic characterizationresults.4. Using1137accessions of wild soybean, collected from the coastal areas of Liaoning, Shandong and Hebei provinces,717alleles were found in29SSR loci,with each locus having a mean of24.74alleles; and the mean of genetic diversityindex was0.7903, with a range of0.6371-0.8682; while the mean of PIC was0.7737, with a range of0.6148-0.8596.5. Based on data of SSR,1137domestic soy bean accessions were clustered into4groups. In the whole1137soybean accessions were clustered irregularly, whichshowed the1137accessions were differentiated in the molecular level. But thoseaccessions in the same group were most from the same province or area.There are many crop resources with salt tolerance in China coastal areas, butthey are facing extinction. The collection and evaluation of crop germplasm resourcesare extremely urgent. The excellent salt-tolerant crop resources screened in this studyprovided the genetic materials for crop breeding to improve salt tolerance. This paperdescribed the methods and index of evaluation for salt tolerance providing the basisfor standard method of evaluation of salt tolerance in crops. The wild soybeanresource collected from China coastal areas had more polymorphism, which providingthe materials for exploring the salt-tolerant gene resources and using this resources inthe soybean breeding.