| Alfalfa is the most important leguminous forage crop, with its good feeding value of high protein contents and great portencial for industrial production. It has been for a long time of very important research interests. In this paper, alfalfa materials collected from northern and southern regions in Xingjiang Uygur Autonomous Region of China and some foreign countries were evaluated by morphological characters, agronomic traits, fall dormancy, nutritional value , seed storage proteins (SSPs) and RAPD markers. Genetic diversity, genetic composition and the relationships among these materials were studied. The main results are as follows:There are more semi-domancy, no-domancy materials among the alfalfa materials (varieties) from foreign countries. The domancy character of materials collected from northern Xingjiang are similar and their dormancies are at level 1. There are some semi-domancy alfalfas in materials of southern Xingjiang, and their dormancy levels are at level 4to5.In the agronomic traits, seed production has the highest variation. Material No.63 has the highest seed setting capacity. Some Medicago falcalta materials produced least seeds. Material No.15 has the greatest capacity of forage production. Most materials of north and south Xingjiang can survive over winter safely. The winter survival rate of the materials which come from foreign countries is at 10%-100%. In terms of forage feeding value, materials of No. 20, No.78, No.87, No.117, No.134 and No.52 have higher crude proteins, higher amino acid and lower crude fibre than the others. In general assessment, Materials of No.63, No.25, No.26 ,No. 134,No.65, No.87, No.101 and No.79 have comprehensive high agronomic traits. They are considered as priority breeding and production materials.Study on seed proteins shows: Materials of northern Xingjiang havemore variations than the materials of southern Xingjiang and the foreign materials. Material No.22 has large genetic distance from all other alfalfa materials, it seemed very special, so it can be used in alfalfa breeding firstly.RAPD results show: the average rate of polymorphic loci of alfalfa is 78.52%. Genetic differentiations estimated by Shannon's index and Nei's index are similar. Materials of No.84 and No.15 have higher heterozygosity, and can be used in alfalfa breeding prioritely.The studies on seed storage protein and RAPD show the similar results that genetic diversities of alfalfa mainly exist within materials. The reason of contrary results displayed by different study methods is that the variations revealed from different levels indicate the variation of different gene loci of all loci genome DNA, and these different loci have different variation levels.Cluster analyses based on morphological characters, agronomic traits, seed storage proteins and RAPD markers have show a similar results: most of the materials indicated that relationships between the materials are related to their geographic distribution. Materials having close distribution area have more chance of gene communication. There are also some exceptions, some materials that distributed far among each others have close genetic distance, which may be explained that them were introduced from same areas long time ago or occurred by cross-pollination when the materials be propagated in the same field. Some closely distributed materials have far genetic distance, which may be caused by different growth eco-environments or the relatively conservative genes.
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