| The aim of the study was to well use the germplasm resources of the Lespedeza davurica, which was widely distributed in the north of China. The experimental material was the different lines and the related species and germplasms that were screened by Grassland Research Institute of Chinese Academy of Agricultural Science. On the base of previous studies, using ecology, morphology, physiology and breeding methods, this dissertation did the variety comparative test, regional test, the salt resistance and drought resistance, seed storage protains, genetic diversity and fingerprint in different lines of the Lespedeza davurica. Through compare to the other related species and germplasms on stress resistance, genetic diversity and fingerprint and so on, revealed the lines characteristics of Lespedeza davurica.1. According to the variety comparative and regional test of four lines of Lespedeza davurica, two outstanding lines of Lespedeza davurica be screened out initially that was line 8 and line 11 . The line 8 has many branches , a big clump diameter , many leaves, and the field performance is more uniform. The hay and seed production is 2823.75 kg/ha, 452.25 kg/ha, respectively. Line11 has long branches , more big clump diameter, many branches, its field performance also better, but its hay and seed production is slightly lower than the line 8.2. The stress treatment of the 4 lines and 2 contrast varieties were conducted by PEG and NaCl at different concentration gradient.The comprehensive analysis of the germination dynamic, the relative germination percentage, the germination power, vigor index and the half-lethal density indicated, the drought resistance and salt resistance order of the 6 materials as follows: contrast species13 > line 11 > line 8 > line 9 > line 10 > contrast species12. The half-lethal density of PEG is 0.84Mpa, 0.72Mpa, 0.69Mpa, 0.66Mpa, 0.58Mp, 0.41Mpa, respectively. The half-lethal density of the NaCl stress is 5.83%, 3.12%, 2.6%, 1.94%,1.6%, 0.78%, respectively.3. Extract seed storage proteins of four L. davurica lines and its relative species and germplasms at individual and population levels, analyzed the genetic diversity and result of clusters. The total genetic diversity of 13 materials was 0.2785, genetic differentiation coefficient(Gst) was 0.6325(>0.51), it showed that there were 63.25% genetic variation between the materials, and 36.75% genetic variation in every samples. The total genetic diversity of 4 Lespedeza davurica lines was 0.1891, genetic differentiation coefficient(Gst) was 0.4185(<0.51), it showed that there were 41.85% genetic variation between the lines, and 58.15% genetic variation in every line. Cluster result showed that 13 materials may gather four kinds: 1 and 13 gathered for the first kind; 2 and 3 gathered for the second kind; 4 and 12 gathered for the third kind; other 7 materials(include the four lines) gathered for the 4th kind. The system cladogram which reflect from the genetic distance indicated: lines and germplasms of Lespedeza davurica has the more close sibships.On the species leve, Lespedeza davurica and L. hedysaroides has the more close sibships, next is the L. cuneata, finally is L. bicolor.4. The comprehensive analysis the variety comparative test, regional test , the salt resistance and drought resistance test result indicated: The line8 of Lespedeza davurica has the best agronomic characters and the field performance, the drought resistance and the salt endurance are only inferior to line11. The line 11 of L. davurica var. has better drought resistance and salt resistance than line8. They both has own distinctive trait, may prior be registered variety.
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