【作者】 徐春明；

【导师】 贾志宽；

【作者基本信息】 西北农林科技大学 ， 生态学， 2003， 硕士

【摘要】 本文研究了不同苜蓿品种的生长动态过程、茎叶比和鲜干比、再生性、群落特性、产量构成以及在生长过程中苜蓿品种的生理生态特性，并对31个苜蓿品种进行综合评价。结果表明： 1．秋眠级数低的品种返青较晚，秋眠级数高的苜蓿品种返青较早。 2．从株高的角度考虑，北疆和侵略者最适合该环境条件，而新牧、保丰、新疆大叶、改革者最不适合该环境条件。 3．从生物量的积累过程及对环境的适应性考虑，巨人、北疆、竞争者、卫士、路宝、13r这几个品种表现较好，适应性较强，columbo、rowdy、朝阳、dll、德国大叶熊这几个品种表现较差，适应性较差。 4．不同苜蓿品种的绝对生长速率和相对生长速率在整个生育期的变化趋势呈单峰曲线。最大值都出现在苜蓿分枝期后期一现蕾期。北疆、中兰、侵略者具有较强的生态适应性。13r、rowdy、columbo生态适应性较差。北疆、vector、德国大叶熊的生产效率较高。rowdy、13r、columbo的生产效率较低。 5．不同生长阶段苜蓿的茎叶比呈上升趋势，使得品质随着生育阶段的推进逐渐下降。苜蓿的鲜干比在不同的生长阶段的变化趋势呈倒“S”型，其变化趋势与生物量的积累紧密关联。 6．株高、分枝数、茎粗和叶面积与苜蓿的生物量积累状况呈正相关。 7．射手、兼用型、牧野和dll具有良好的株型结构，具有高产和优质的潜力。保丰、牧歌、竞争者和gs88-rn株型结构不太合理，影响了品质。 8．不同的苜蓿品种的生产结构有所不同。保丰、巨人、爱林、新疆大叶的生产结构比较合理。朝阳、爱维兰、德国大叶熊、vectot的生产结构不太合理。 9．不同苜蓿品种的产量差异比较明显，北疆、牧歌、affinity的年总产量较高，经济性能较好；改革者、卫士、竞争者的年总产量较低，经济性能较差。columbo、卫士、d11在一年内的产草量较为稳定；中兰、路宝、牧歌在一年内的产草量较不稳定。 10．不同苜蓿品种的再生速度以第一茬为最大，第二茬次之，第三茬最小。不同苜蓿品种的再生性有较大的差异，德国大叶熊、北疆、13r的再生性较好；而朝阳、保丰、gs88-rn的再生性较差。 11．不同生育阶段苜蓿蒸腾速率一直在增大。改革者、爱博、vector、affinity受水分胁迫影响较小；而新疆大叶、侵略者、超级阿波罗和dll受水分胁迫影响较大。vector、全能、兼用型、改革者经济用水能力较强；巨人、爱维兰、竞争者、中苜经济用水能力较差。改革者、全能、affinity、北疆和射手同化CO₂能力较强，巨人、竞争者、爱维兰和德国大叶熊同化CO₂能力较差。逐步回归分析表明苜蓿的光合速率与蒸腾速率、气孔导度、WUE、气孔腔与大气的湿度差以及气孔腔与大气的CO:浓度差的相关性均已达到极显著水平。 12.以再生速度、气孔导度、卿E、光合速率、叶茎比、鲜干比、株高、产量、最大生物量累积潜力、最快积累时间和最大积累速度为指标利用突变评价方法对不同首稽品种进行最终评价，排名在前十位的品种有改革者>侵略者>全能>巨人>德国大叶熊>美国杂交熊>北疆>爱博>射手>超级阿波罗，这十个品种在该地区的综合表现良好值的推广;排名在后十位的品种有rowdy<朝阳<dll<保丰<9588一rn<卫士<新疆大叶<新牧<中首<columbo，这十个品种在该地区的综合表现较差应慎重推广。更多还原

【Abstract】 Dynamic growing process, stem-leaf ratio, fresh-dry ratio, regrowth characteristics, community characteristics, yield characteristics and physiological ecological characteristics of different alfalfa varieties have been studied, and growing characteristics of thirty-one alfalfa varieties has been evaluated comprehensively in this paper.It is concluded that:l.The reviving stage of varieties with high fall dormancy scale is earlier than that of varieties with low fall dormancy scale.2.As far as the dynamic of plant height is concerned, Beijiang and Aggressor are the most suitable for the environment of location area. Xinmu, Baofeng and Innovator are poorly suitable for the environment of location area..3.As for the accumulation of biomass and adaptiveness of environment, the adaptiveness of Ameristand, Beijiang , Runner, Ameriguard, Lobo,13r is better. However, that of Columbo, Rowdy, Jacklin, Dll and Deguodaye is poor.4.The dynamic of AGR and RGR shows a monopeak curve in whole developing stage of different alfalfa varieties. The AGR and RGR will reach the maximum from late of ramification stage to budding stage. The ecological adaptiveness of Beijiang, Zhongmu Aggressor is strong, however, that of 13r,Rowdy,Columbo is weak. Beijiang ,Vector and Deguodaye have higher product efficiency. The product efficiency of Rowdy , Columbo and 13r is lower.5.With the stem-leaf ratio increasing in different growing stage, the quality of alfalfa will decrease. The dynamic process of fresh-dry ratio of alfalfa shows reversing "S" curve. It has closely correlated to the accumulation of biomass.6.Plant height, ramification number, stem diameter and leaf area have significantly positive correlation to accumulation of biomass.7Archer, Haygraze, Alfagraze and Dll have better plant-type formation and great potentiality of high production and good quality. Baofeng, Amerigraze, Runner and Gs88-rn have poor plant-type formation ,moreover, poor plant-type formation result in reduction of quality.8.Different alfalfa varieties have different productive structure. The productive structure of Baofeng .Ameristand, Abilence, Xinjiandaye is reasonable.However, that of Jacklin, Avalanche, Deguodaye, Vector is unreasonable.9.There exists significant yield difference among different varieties. Beijiang, Amerigraze and Affinity have better economic character and higher yearly yield. Innovator, Ameriguard and Runner have worse economic character and lower yearly yield. The yield of Columbo, Ameriguard and Dll is more stable. While that of Zhonglan, Lobo and Amerigraze is more unstable.10.With the increasing of cutting times, the regrowth rate is decreasing. There exists significant difference of regrowth character among different alfalfa varieties. The regrowth character of Deguodaye , Beijiang and 13r is strong, and that of Jacklin, Baofeng, Gs88-rn is weak.11.The transpiration of alfalfa is increasing during the whole developing stage. Waterstress has less effect on Innovator, Arriba and Affinity, and has larger effect on Xinjiangdaye, Aggressor, Apollo supreme and Dll. Varieties with higher WUE are Vector, Total and Haygraze. Varieties with lower WUE are Ameristand, Avalanche, Runner and Zhongmu. Assimilation of ability of Innovator, Total, Affinity, Beijiang and Archer is strong, however, that of Ameristand, Runner,Avalanche and Deguodaye is weak. Stepwise regression analysis indicates that photosynthesis rate has significant correlation to transpiration rate, stomatal conductance, WUE, the difference of relative humidity and CO2 concentration between leaf and ambient air.12.Thirty-one alfalfa varieties have been evaluated, with the regrowth rate, stomatal conductance, WUE, photosynthesis, leaf-stem ratio, fresh-dry ratio, plant height, yield, the maximum accumulating potentiality of biomass, the most quickly accumulating time of biomass, and the maximum accumulating rate of biomass as evaluation criterions, by means of catastrophe evaluation. It is concluded that, varieties, with better comprehen更多还原