【作者】 赵桂琴；

【导师】 胡自治； 曹致中；

【作者基本信息】 甘肃农业大学 ， 草业科学， 2000， 博士

【摘要】 为了培育出放牧型早熟禾新品种，以14份早熟禾为材料，对其生育期、开花习性、生产性能和营养成分进行了观测记载和分析，根据育种目标，选出4个材料作亲本，制定了7个杂交组合，分别用温汤去雄杂交、化学去雄杂交和人工去雄杂交对其进行去雄效果的研究，对人工去雄杂交所得的杂种进行了染色体数目和同功酶方面的鉴定，对各杂交组合的杂种进行了杂种优势预测，并对杂种营养生长期的表现进行了观测和分析，初步表明了杂种优势预测方法的正确性和预测结果的可靠性。 从生育期看，草地早熟禾的生长天数远远大于其他种的早熟禾，绿期最长。结合育种目标，从14份材料中初选8份供进一步分析研究。开花习性的调查结果表明，早熟禾为圆锥花序，开花顺序是从上至下，花期一般为1～2周，开花强度以开花后第5～11天、每天早晨4：00～10：00为最盛。 生产性能的测定表明，8份初选材料的青草产量之间存在极显著差异，并与分蘖数、株高和生长速度之间呈一定的正相关，由此得出它们之间的回归方程。品质分析首先对初选材料的茎叶比进行测定，方差分析表明，不同材料间茎叶比差异显著，结合生产性能和育种目标，最终选出4个亲本材料，分别为莫诺波利（Monopoly）草地早熟禾、瓦巴斯（Wabash）草地早熟禾、恩托佩（Storpy）草地早熟禾及扁秆早熟禾。对其进行营养成分分析，结果显示，它们在粗蛋白和酸洗纤维方面存在显著差异，据此选出7个杂交组合，分别为：瓦巴斯×思托佩、思托佩×瓦巴斯、思托佩×扁秆早熟禾、扁秆早熟禾×思托佩、莫诺波利×瓦巴斯、扁秆早熟禾×瓦巴斯、瓦巴斯×扁秆早熟禾。 首次用温汤去雄对早熟禾进行杂交，不同材料去雄杂交效果不一样，3个草地早熟禾品种的最佳处理均为47℃-2min，扁秆早熟禾为47℃-3min和48℃ －lmin，反映出栽培种和野生种在逆境抵抗能力方面的差异。温汤去雄用于早 熟禾杂交至今尚未见报道。首次用美国生产的GENESIS化学杀雄剂对早熟禾 进行化学去雄杂交，最佳喷施剂量为1．skg儿。 首次用人工去雄进行早熟禾杂交，并对温汤去雄和人工去雄的杂种从染色 体数目及同功酶方面进行了鉴定，用过氧化物同功酶对杂种优势进行了预测， 结果表明，不同杂交组合杂种优势强弱不同，杂种酶谱呈互补型或有特异带、 酶活性总面积大的杂交组合如莫诺波利X瓦巴斯、瓦巴斯X思托佩、扁秆早熟 禾X思托佩；杂种优势较强，反之则弱，如思托佩X瓦巴斯。 温汤去雄、化学去雄及人工去雄的杂种出苗率及出苗速度显著低于亲本。 营养生长期观测结果表明，杂种在扩展能力、叶长、叶宽等方面均比亲本优越， 初步表现出较强的杂种优势，也表明了杂种优势预测方法的正确性和预测结果 的可靠性。更多还原

【Abstract】 In this paper, life history, flowering habit and productivity of 14 materials of Poa were studied for about 2 years. According to the breeding objective, 4 materials were selected as parents and 7 hybridization groups were made. The female parent was emasculated with hot water, chemical hybridizing agent and artificial method, respectively. The hybrids of artificial emasculation were identified from morphology, chromosome number and isoenzyme and their heterosis was also predicted in this study. The result of life history shows that the life span of Poa pratensis is much longer than other materials. Considered with breeding object, 8 materials were selected for further study. The flowering habit indicates that the panicle of Poa flowers from top to the bottom, the florescence varies from one to two weeks, in which the fifth to eleventh day, from 4 a.m to 10 a.m, is the most prosperous. Productivity shows that fresh yield of 8 material varies remarkably, and has a positive correlation with tillering number, height and growth speed. The result of quality indicates that the ratio of stem weight and leaf weight has a very great difference. Combined with productivity and nutrition, 4 from 8 materials were selected as final parents. The hybridization groups are Monopoly X Wabash, Wabash X Storpy, Storpy X Wabash,Storyp X Poa pratensis var.anceps, Poa pratensis var.anceps X Storyp, Wabash X Poa pratensis var.anceps, Poa pratensis var.anceps X~Vabash. Emasculation with hot water indicates that the best treatment of Poa pratensis is 47C-2min, 4TC-3min and 48扖-lmin for Poapratensis var.anceps. GENESIS was used as a chemical hybridizing agent in the study, the best rate is 1 .5kg/bin2. Compared with former treatments, artificial emasculation is much more reliable, its hybrids were identified from chromosome number and isoenzyme, and its 3 heterosis was predicted by peroxidase isoenzyme, which indicates that different hybridization group has different heterosis. Fl with hybrid isozyme pattern or complementary isozyme pattern are good, such as Monopoly X Wabash, Wabash X Storpy, while that of hybrid with no difference isozyme patterns or delete isozyme patterns are poor, such as Storpy X Wabash. Heterosis is also positively correlated with enzyme active areas. The result of seedling character from hybrids and parents shows that the hybrids are superior to parents in invasion ability, leaf width and leaf length, which indicates the correctness of the method of heterosis forecast and the reliability of its result.更多还原