| Leymus chinensis (Trin.) Tzvel.,member of gramineae.Leymus,is a very important forage species. It was not only the king of gramineae forage due to high protein content,palatability to cattle and adaptability to surroundings,but also a major candidate in artificial grassland construction and improving ecotype as well. In recent years,however,owing to the exacerbated environment problems,overload on grassland and the "three low problems"(low setting percentage,low germination percentage,low grass productivity),the population of L. chinensis has become more and more degenerated which restrict the artificial grassland construction,natural grassland improvement and control of deserted land. Thus,it is very urgent to strength research and protect the biological diversity of L. chinensis. So far,there are limited reports abroad in this area,meanwhile,the papers published in China mostly concentrate on macroscopic aspects such as grassland ecology et. Furthermore,less systematic research work and reports are focused on reproduction biology. In this paper,initial research work have been done from four aspects as listed as below with collected L. chinensis. germaplasm resources from out and all over the country:Firstly:Correlation analysis between reproduction character and genetic diversity molecular marker index of L. chinensis. Seventeen accessions were selected arbitrarily from collected germplasm resources. The identification on species of L. chinensis was carried out based on both RAPD and morphological data. The results suggested that only nine of them were object species occupying 53% among all experiment materials. The conclusion revealed it was reliable that RAPD marker was used in identification and evaluation on germplasm resource of L.chineses. Compared with morphological data,RAPD marker offered an efficient means to determine this species with the advantages such as rapidly,reliably and no influenced by environment events. Twenty-one primers were screened from 40 ten mer arbitrary primers,and a total of 115 DNA fragments were amplified ranging from 0.2-5.5 kb in 9 L.chineses,among which 95 (82.61%) were polymorphism. Ten specific bands-S1213-900,S1213-1700,S1215-5500,S1396-1370,S1384-900,S1202-5180,S1220-2200,S1381-1580,S1211-2800,S1211-800 were found in nine genotypes of L.chineses. Furthermore,the samples of L.chineses could be distinguished out with the 10 special marker. The correlation analyzed between based on morphological data and on RAPD data showed that there were some correlation between number of spikes,weight of thousand seeds,leaf color,the level of sexual propagation,setting percentage and index of genetic diversity. Additionally,the problems in the process of collecting,arranging,evaluating for accession of L.chineses were discussed.Secondly:Comparable research on asexual reproduction biological character of different L. chinensis. genotypes. Analysis was conducted on six cloning morphological character index-leafnumber increment bud number increment,bud height,bud distance,bud weight,root number of 10 L. chinensis. genotypes. The genotype Jisheng-1 was chosen as control and the experimental ecological factors are the same. The results showed that:genotype difference is a very important influencing factor for the cloning growth and development of L. chinensis,both environmental factor and genotype factor should be considered in the future research on asexual reproduction biology of L. chinensis. Between the 10 genotypes,morphological character index was obviously different. Furthermore,compared with other genotypes,Zai-3 genotype had better character index than Jisheng-1. All these conclusions will provide foundation for future breeding research work of L. chinensis.Thirdly:Establishment of regeneration system of L. chinensis through culture in vitro. Immature-stachys-base explants were cultured on Murashige and Skoog's basal medium (MS) supplemented with 2 mg/L 2,4-D after surface sterilized with 0.1% HgCl2 to induce callus at 25 C constant temperature. After moved to M...
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