【作者】 张志；

【导师】 苏德荣；

【作者基本信息】 北京林业大学 ， 草学， 2016， 硕士

【摘要】 紫花苜蓿(Medicago sativa L.)是多年生豆科苜蓿属草本植物。其营养价值高、适口性好、具有广泛的生态适应性、产出年限长,可以提高农田质量,增加土壤含氮量,被广泛用作饲料原料,是家畜喜食的牧草之一,素有“牧草之王”的美称。为了探究外施硅肥对于紫花苜蓿生长和品质的影响以及确定最佳硅肥施量,分别进行了两年的试验。第一年设计并进行了盆栽试验,模拟水硅一体化的地下滴灌装置,设置4个硅肥水平(0,0.01,0.02,0.03 g.kg-1,以每千克土施用Si02的克数)处理,每个处理5次重复。第二年进行紫花苜蓿大田试验,滴灌水硅一体施肥,设置了5个硅肥外施量(CK,S1,S2,S3,S4)。研究结果表明：1、盆栽试验施硅植株生长指标要显著好于不施硅的植株(P<0.05)。试验观测的两个茬次的苜蓿,施硅的处理植株相比于对照组,其产量、叶面积、鲜干比、节间距、节间数等指标有显著的提高(P<0.05)。不同茬次对比,施硅处理对于苜蓿生长初期的促进作用要大于生长后期。施用硅肥对苜蓿营养指标的影响不明显,在施硅量为0.02 g·kg-1的处理相对于对照组粗蛋白含量高,纤维素含量最低,并且0.02 g.kg-1处理的植株有较高的相对饲喂价值。2、大田试验外施硅肥能够促进紫花苜蓿植株生长。施用硅肥的四个处理(S1, S2, S3, S4)相比于CK,第一茬叶面积增大68.0%-117.2%,第二茬增大37.9%-133.7%；第一茬鲜干比增大9.5%-37.7%,第二茬增大15.7%-33.3%；第一茬植株生长前期株高增长量增加50.0%-163.2%,第二茬增加22.0%-46.5%;第一茬生长中期株高增长量增加27.2%-69.7%,第二茬增加10.5%-44.4%；第一茬节间距增加14.9%-32.5%,第二茬增加13.6%-39.3%；第一茬节间数增加15.8%-32.2%,第二茬增加25.0%-65.0%；第一茬干草叶质量提升49.8%-80.6%,第二茬提升了13.6%-39.3%；第一茬干草产量增加了53.5%-96.9%,第二茬增加18.2%-46.4%。施用硅肥的植株,施肥量为105g/m2对苜蓿生长的促进能力高于其他施硅处理。更多还原

【Abstract】 Alfalfa (Medicago sativa L.) is a perennial legume herbs of the genus Medicago. Alfalfa has high nutritional value and good palatability. It has widely ecological adaptability and highly output. Alfalfa lives long and it is a green manure planted in the fall. Alfalfa can improve the quality of farmland and increase soil nitrogen content. It is widely used as forage for livestock. Alfalfa is known as "the king of forage" reputation. In order to explore the influence of integration of irrigation water and fertilizer on the growth and quality of alfalfa under drip irrigation (SDI), the pot culture experiment and field experiment were carried out. The pot culture experiment had four treatments of silicon concentrations (SO,S1,S2,S3) and five duplicates for every treatment. The field experiment had five treatments of silicon fertilizers concentration (CK, S1, S2, S3, S4) and three duplicates for every treatment.1. The potting experiment showed that six growth indexes of alfalfa applied silicon fertilizer were higher than that of without silicon fertilizer. As for the quality of alfalfa hay, CP with 0.02 g· kg-1 silicon fertilizer was the highest, NDF with 0.02 g·kg-1 silicon fertilizer was the least. So the conclusion was that the integration of irrigation water and silicon fertilizer under subsurface drip irrigation can promote growth of alfalfa and silicon fertilizer promote the early growth stage of alfalfa more than the late growth stage of alfalfa.S2 plants has higher quality than other plants.2. The field experiment showed that silicon fertilizer was positive to promote alfalfa growth. Compared S1, S2, S3 and S4 to CK, the leaf areas increased 68.0-117.2% and 37.9-133.7% for the first and second cut respectively; the ratio of green to hay increased 9.5-37.7% and 15.7-33.3% for the first and second cut respectively; the increment of early growth stage heights increased 50.0-163.2% and 22.0-46.5% for the first and second cut respectively; the increment of middle growth stage heights increased 27.2-69.7% and 10.5-44.4% for the first and second cut respectively; the intermodal distance increased 14.9-32.5% and 13.6-39.3% for the first and second cut respectively; the number of internodes increased 15.8-32.2% and 25.0-65.0% for the first and second cut respectively; yield increased 53.5-96.9% and 18.2-46.4% for the first and second cut respectively; dry leaf weights increased 49.8-80.6% and 13.6-39.3% for the first and second cut respectively. S3 promote alfalfa growth at the most extent when compared to S1, S2 and S4, which the research results implied that 105g/m2 was the optimum concentration of silicon fertilization for alfalfa growth.更多还原