| AfoastractIn order to speed up the exploitation of germplasm resourse of native Hemarthria R.Br., and find some excellent accessions, which aims to improve the conditions of cultivar sarcity. poor quality and narrow adaption existed in the application of H.compressa at present, 19 native accessions collected from Sichuan, Chongqing and Shanghai were experimented through plot trials, and simultaneously two released cultivars 'H.compressa cv. Guangyi' and 'H.compressa cv. Chongqing' were tested as the controls.Each accession agronomic traits, genetic diversity in the level of isoenzyme were compared and analysed. In addition, a primary study was carried out on the acid and alkali-resistance and salt-tolerance of H.compressa cv. Guangyi as well as an expriment on the technique and effect of chemical control of weeds(mainly Alternanthera philoxeroides) for it, which provides a useful reference for the application and development of native accessions further. The result shows:(1) Among the 21 accessions, H19(from Caoba of Sichuan, China) shows many good characters of grazing grass such as high and strong stem,rich leaf and high dry matter(DM). Furthermore,its crude protein(CP) is higher up to 3.0 % than that of H20(CK). Therefore,there is a promising for the HI9 to offer an alternative to be a new cultivar. H13(from Qionglai of Sichuan, China) is supposed to be a good kind of turfgrass because of its smallest internode diameter and narrower foliar width among all the accessions. Positive correlations were found between plant natural height, tillers,DM yield, foliar length and width, stem diameter, internode length,and the significant correlation was respectively found between natural height and internode length(r=0.726), DM(r=0.658),stem diameter(r=0.615) at the level of 0.01. Besides negative correlations were found between leaf to stem rate and CP, and their absolute value were so small that nearly up to no correlations. It was also found that there was a long vegetative period before head sprouting in all wild accessions and a poor rate of seed set.(2) 'H.commpressa cv.Guangyi' has a good adaption in acid soil with 4.5-6.2 pH values and it can grow normally in the salty soil with 0.1 %~0.3 % salinity.(3) A herbicide variety on Alternanthera philoxeroides was studied in the grass field of 'H.commpressa cv.Guangyi'.Compared with CK,the herbicide made the control efficiency to 26.7 % -99.8 % and it was safe for 'H.commpressa cv. Guangyi' under higher control efficiency. According to the different field trials, the control efficiency was excellent to 100 % with a dosage of 0.7-0.9 1/hm2 and it made the efficiency of control42above 90.0 % with a dosage of 0.5-0.7 1/hm2. However, it should better with the latter dosage considering of the economical factor.(4) 10 bands of peroxidase were found to migrate into two regions with Rf value 0.06-0.08 and 0.54-0.73 and exists significant difference between them inflecting the rich genetic basic, and 2 banks of esterase migrated into only one regions with Rf value 0.74 and 0.76 and exists little difference and similar inheritance among the specimens. It indicated by the hierarchical clustering analysis(HCA) that all accessions are divided into four types and a closer relation existed between H.compressa cv. 'Guangyi' and H09(from Caoyu lake of Sichuan, China) and H03(from Jinfeng temple of. Sichuan, China), H12(from Shanghai, China) and H06(from Hongya of Sichuan, China) showing a further relation with other accession.The peroxidase isoenzyme analysis is a useful technique for the study of genetic diversity,as well as a warrant for the cultivar identification in Hemarthria spp. in spite of its limitation.
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