【作者】 徐胜；

【导师】 张新全； 吴彦奇；

【作者基本信息】 四川农业大学 ， 草业科学， 2002， 硕士

【摘要】 为了加快开发野生牛鞭草(Hemarthria altissima)种质资源，选育出性状综合优良的新品系，改善当前牛鞭草品种单一、质量欠佳、适应性较差等缺点，本试验以四川、重庆、上海等地搜集的19份扁穗牛鞭草(H.compressa)为研究材料，以“广益”(H.compressa cv.’Guangyi’)和“重高”(H.compressa cv.’Chonggao’)牛鞭草为对照，通过小区引种试验，对其农艺性状以及酶水平上的遗传变异等方面进行了比较研究。此外，还以“广益”牛鞭草为材料，进行了牛鞭草的抗酸碱、耐盐性以及牛鞭草草地杂草(主要为水花生)防除技术研究，为进一步利用野生扁穗牛鞭草种质资源提供生产适应性依据。结果表明：(1)21份材料中，H19(草坝扁穗牛鞭草)表现出植株高大、茎干粗壮、叶量丰富、干物质含量高等许多牧草的优良特点，而且其粗蛋白含量相对于H20(“广益”牛鞭草)高约3.0％，所以，它有望成为新型的优良扁穗牛鞭草品种；H13(邛崃扁穗牛鞭草)的节直径在各材料中最小，茎干较细，而且叶片较窄，匍匐性强，可望成为良好的草坪地被植物。各材料的株高与干物质重量、分蘖数、叶长、叶宽、茎直径、节间长存在正相关，且与节间长、干物质、茎直径相关极显著(0=0.01)，相关系数分别为0.726、0.658、0.615。株高与茎叶比和粗蛋白呈负相关，但相关不显著。野生材料在抽穗前较对照有较长的营养生长期，并且有极低结实率，有的很难见到结实。(2) “广益”牛鞭草在偏酸性土壤中表现良好，适宜的pH值为4.5～6.5：在氯盐含量为0.1％～0.3％的土壤中仍能正常生长。(3)利用水花生净可有效地防除牛鞭草草地中的空心莲子草，株防效达26.7％～99.8％，并且在较高防效下，药剂对牛鞭草较为安全。水花生剂以0.7～0.9 l/hm~2的用量防除效果最佳，均达到100％，而以0.5～0.7 l/hm~2的防除效果也在90％以上。但如考虑经济因素，以0.5～0.7 l/hm~2的用量为宜。(4)过氧化物酶同工酶显示出10个酶位点，其泳动形成2成个区域，R_f值分别为：0.06～0.18、0.54～0.73，各材料间的遗传差异较为明显，表现出丰富的遗传基础；酯酶同工酶显示出2个酶位点，只形成一个泳动区域，R_f为0.74和0.76,各材料间遗 传差异甚小，表现出相当高的同源性。聚类分析表明，各材料可分为四个大的类群。 “广益”牛鞭草和＊09（槽渔滩扁穗牛鞭草）亲缘关系较近：“重高”牛鞭草与＊03 （金凤寺扁穗牛鞭草）亲缘关系较近；HIZ（上海扁穗牛鞭草）与 H06（洪雅扁穗牛 鞭草）亲缘关系较近，而与其它扁穗牛鞭草甚远；重庆的几个扁穗牛鞭草的亲缘关 系较近。过氧物化物酶同工酶图谱为扁穗牛鞭草种质的起源、分类以及遗传多样性 的鉴定提供了可能，但还存在一定的局限性。更多还原

【Abstract】 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.更多还原