【作者】 李瑛；

【导师】 李卫军；

【作者基本信息】 新疆农业大学 ， 草业科学， 2004， 硕士

【摘要】 本文通过对一年龄制种苜蓿进行不同时期和不同灌水量处理，研究了不同水分条件下，土壤水分变化及其对苜蓿植株生长发育、结实特性、种子产量相关性状及种子产量的影响。灌水处理分别在现蕾期和结荚期进行，每次灌水 分 75mm、120mm 和 180mm三个水平。 结果表明，在苜蓿生长早期，即返青期至分枝期，土壤水含量较高，不需要灌水。在现蕾期，当土壤含水量降至田间最大持水量 50%以下时，需进行灌水。灌溉主要影响0-50cm 苜蓿根系分布层内的土壤含水量，随着灌水量的增加，湿润层随之加深，180mm灌溉量的湿润层可达 70cm 甚至更深。在结荚期灌水后，土壤水分蒸散量减少，土壤含水量下降速度趋缓。 不同的灌水时期和灌水量对苜蓿的生长和结实均有影响，灌水时期的作用要比灌水量的作用大。现蕾期灌水有利于花芽分化，促使苜蓿开花、授粉和结荚过程能集中完成。结荚期灌水对苜蓿的生长速度和植株高度的影响不大，但会引起苜蓿同化产物的再分配，导致生殖生长后延及种子的败育。 不同灌溉处理间的单株荚果数、每生殖枝荚果数差异极显著，每荚果小荚数差异显著。其中在现蕾期末灌水量为 180mm 的 T7，单株荚果数最高，为 103 个/株，而种子产量为所有处理最高值，达 400.64Kg/hm2。T7在每生殖枝荚果数、每荚果小荚数、单株种子重等产量构成因素及种子实际产量上，也同样最高。 灌溉水利用效率随着灌水量的增加而减少。对于相同的灌水量，其利用效率视灌溉时期而定，现蕾期分配较大水量可达较高利用效率。在一定气候条件下，苜蓿种子生产的适宜调亏灌溉时间在结荚期。更多还原

【Abstract】 Through different irrigation treatments, we studied on the change of soil water and therelationships between one-year-Alfalfa growth, fructification, seed yield component, seedproduction and the change of soil water. Irrigation treatments were done during budding stageand pod stage. And three irrigation levels were designed: 75mm, 120mm, 180mm. Results showed that during Alfalfa growth stage to branching stage when the soil watercontent was relatively high, irrigation was not carried out. In the budding stage, Alfalfaneeded to be irrigated as the soil water content reduced at 50% of field capacity. Irrigationinfluenced the soil water content in 0-50 cm soil. Damp soil was increased with adding waterso 180mm water can saturate 70 cm soil. In the pod stage，the ratio of soil water loss waslessen. Alfalfa growth and fructification was influenced by the time and the quantity of irrigationand the time is important. When the irrigation was done at budding stage, alfalfa can flower,fertilization and pod in a centralized time. Pod stage irrigation did not much influence theheight of plant and growth speed but it caused the reproduction stage delayed and the moreabortive pods. The number of pods per plant, the number of pods per shoot and the number of pods perinflorescences had significance difference among different irrigation treatments. T7 wastreated by 180mm irrigation water at budding stage, which of the number of pods per plantwas the most: 103 pods per plant. Moreover, which seed yield of T7 was much more thanother treatments was 400.64Kg/hm2. The seed components of T7, such as the number of podsper plant, the number of pods per shoot , the number of pods per inflorescences and the seedproduction per plant was also much more than others. Irrigation-water use efficiency (WUEi) was increased by added water amount. For theequal amount the efficiency had relation with the time of irrigation. While it was at buddingstage WUEi was high. Under certain climate, the proper time of regulated deficit irrigation isin the pod stage for alfalfa..更多还原