【作者】 赵艳；

【导师】 魏臻武；

【作者基本信息】 甘肃农业大学 ， 草业科学， 2008， 硕士

【摘要】 本文对13个来源不同的苜蓿品种进行了根系特征调查、根部各指标相关性分析、根系特征各指标形态学聚类分析、鲜草产量的聚类分析、苜蓿根系形态特征与草产量关系的研究。研究结果如下:对13个秋播苜蓿品种的根系生长性状进行调查研究,结合产草量分析表明:不同苜蓿品种间根系的生物量和侧根数差异显著(P<0.05),其中Prime和WL323的根系生物量最高在32 g以上,WL323的侧根数最多为17.8枝,草原2号、润布勒根冠周长最大,WL323根系体积最大。天水、陇东、WL323冠芽数最多。综合评价Prime、WL323、Super7和L90等4个品种的根系生长性状最佳。在一年的3次生长生产中,苜蓿自身根系的生长发育与第1次和第2次地上生长生产形成相互促进关系,而与第3次生长生产形成竞争关系,进入越冬时苜蓿根系的好坏制约着次年的产草量,特别是次年第3次的产草量。对各品种根部指标进行相关性分析表明:根系各指标中,除冠芽外,其余各指标(包括根颈周长、侧根数、体积、根系生物量)都成正相关。苜蓿草产量聚类分析表明:第一类草产量相近的有陇东、草原2号、德福、陇中,产量较低;第二类草产量相似的包括L90、Super7、L33、WL323、天水、等5个品种,草产量中等;第三类包括赛特、润布勒、Prime、新疆大叶等4个品种,草产量最高。所选8个自交单株中,多叶型和高植株型自交率最高,分别为61.54%和68.04%。多叶型S1和高植株型S1都分离为3种类型即:直立型、匍匐型、半直立型,其中匍匐型产量表现最好。研究表明,生活力高的植株对环境的适应能力较强,可能持久性由它的优良基因有关系。在育种程序上个体特征由潜在的基因所决定,例如,草产量。我们的研究显示,依据根系特征培育一个更优良的品种需要较大的选择范围,而且这个品种总体上表现优良才是最重要的。综上所述,苜蓿草产量的高低与根系特征成正相关,根系特征决定植物产草量的潜能,而且还与品种有关。更多还原

【Abstract】 A study was conducted to determine root system characteristics , the correlation analysis of index in root system, cluster analysis of the root system morphology among alfalfa cultivars, Cluster analysis of the yield among alfalfa cultivars,root system growth character and their correlation with the yield of alfalfa for different alfalfa varieties,etc,of thirteen alfalfa with different origins.The results were shown as follow:Study on the growth character of root system among alfalfa cultivars which were seeded in autumn was carried out and the results indicated that there were significant difference in root system biomass and the number of secondary root among alfalfa cultivars (P﹤0.05), the cultivars, Prime and WL323, had the best performance in root system biomass and reached above 32 gram, Meanwhile, WL323 had the most secondary root was17.8, Cao yuan2,ramble had the best perimeter of root system,WL323 had the best volume of root system,Tian shui,陇东,WL323 had the best crown root .the comprehensive evaluation of root system , Prime, WL323, Super7 and L90 were the better than other cultivars; In 3 produces for a year, the overground growth of alfalfa promoted root system growth oneself in the 1st-time and the 2nd-time produce, however, bated root system growth oneself in the 3rd-time produce, the growth character of root system before got into winter restricted the produce of next year, especially the 3rd-time produce in next year.Correlation analysis indicated that,except for crown root,other indexes of root including perimeter of root system, volume of root system, height of root system, lateral root number, was significantly or high significantly positive correlation.Cluster analysis of the yield among alfalfa cultivars indicated that t he frist yield similar, including Long dong,Cao yuan2,Defy,Long zhong, the second includingL90, Super7,L33, WL323,Tian shui,the third including Sitel,Rambler,Prime,Xin jiang da ye。The eight plant were selfed. multi-leaves type and Erect type had the best selfed percent, selfed percent reached 61.54% and 68.04%. S1of multi-leaves and S1of Erect type becames threes type,They are Erect type ,Grivel type, half erect type.Yield of the grivel type is the best high. Our study revealed that plant surviving are likely to have been subjected to a wide array of natural selection pressures and may represent a valuable source of genes for trait related to persistence.Their eventual utilization in breeding programmes depends on the genetic potential of respective individuals for other equally important traits,for example,forage yield.Our study revealed that research involving a wider range of cultivars and plant introduction can be grounped based on root system characteristics.Taking all these factors into consideration, ,forage yield and root system characteristics was significantly or high significantly positive.Forage yield potential of plants was determined with correlation. root system characteristics and cultivars characteristics.更多还原