紫花苜蓿不同高度的生长特性及分层刈割高度研究

发布时间：2018-03-25 07:47

本文选题：紫花苜蓿　切入点：分层收获　出处：《北京林业大学》2015年硕士论文

【摘要】：以紫花苜蓿皇冠为试验材料,采用大田切片法在初花期自留茬5cm以上每10cm为一层进行切片,测定三茬紫花苜蓿不同层高的生物量、叶茎比、茎的直径、分枝长、叶面积等生长特性与粗蛋白、中性洗涤纤维,酸性洗涤纤维等营养物质含量。对比了紫花苜蓿在不同层高的生长特性与品质指标的差异。并以此数据为基础,对比了以不同分层刈割高度收获的上、下两部分植株在生物量与营养物质含量上的差异。提出了分层刈割高度和分层高度比的概念。研究结果表明：(1)紫花苜蓿在不同离地高度的各层生物量表现出差异性,各层的分枝长和平均叶面积越靠近底部和顶部越小,各层的叶茎比随着离地高度的增加呈指数级增加,最上层达到2.30～4.77。粗蛋白质含量越靠近植株顶部越高,最上层比最下层高12.01～17.37%；中性洗涤纤维含量越靠近植株顶部越低,最上层比最下层低26.78～30.37%；酸性洗涤纤维含量同样越靠近植株顶部越低,最上层比最下层低24.79～27.33%；相对饲喂价值越靠近植株顶部越高,最上层为最下层的2.58～3.16倍。(2)按照不同的分层刈割高度收获的紫花苜蓿,得到的上部分植株比下部分植株叶茎比高,粗蛋白含量高,中性洗涤纤维含量与酸性洗涤纤维含量低,相对饲喂价值高即上部分植株品质优于下部分。随着分层高度比的升高,上部分生物量减少,下部分生物量增加,分层收获得到的上、下两部分植株的叶茎比均升高,粗蛋白含量均升高,中性洗涤纤维含量与酸性洗涤纤维含量均降低,相对饲喂价值均升高,即上、下两部分品质均变好。
[Abstract]:Using the crown of alfalfa as the experimental material, the field slice method was used to slice each layer of 5cm above the stubble at the beginning of flowering. The biomass, leaf stem ratio, stem diameter and branch length of different layers of three crops of alfalfa were measured. The growth characteristics of alfalfa were compared with the contents of crude protein, neutral detergent fiber, acid detergent fiber, etc. The growth characteristics and quality indexes of alfalfa in different layers were compared. The harvest at different cutting heights was compared. The difference of biomass and nutrient content between the next two parts of the plant. The concepts of stratified cutting height and stratified height ratio were put forward. The results showed that the biomass of different layers of alfalfa was different at different height. The branching length and the average leaf area of each layer were smaller than those of the bottom and the top, the leaf stem ratio of each layer increased exponentially with the increase of the height from the ground to the top of the plant, and the highest layer reached 2.30% 4.77.The content of crude protein was higher as the content of crude protein was closer to the top of the plant. The upper layer is 12.01% higher than the lowest layer 12.01% 17.37%; the higher the content of neutral detergent fiber is, the lower the content of neutral detergent fiber is, and the lower the content of acid detergent fiber is, the lower the content of acid detergent fiber is to the top of the plant, and the lower the content of acid detergent fiber is to the top of the plant. The higher the relative feeding value was, the higher the relative feeding value was, and the higher the relative feeding value was, the higher the relative feeding value was, the higher the relative feeding value was, the higher the relative feeding value was, the higher the relative feeding value was, the higher the relative feeding value was, and the higher the relative feeding value was, the higher the leaf stem ratio of the lower layer was, the higher the leaf stem ratio was to the upper part of alfalfa harvested according to different cutting height. The content of crude protein was high, the content of neutral detergent fiber and acid detergent fiber was low, and the quality of the upper part was better than that of the lower part. With the increase of stratification height ratio, the biomass of the upper part decreased, the lower part of the plant increased. The leaf stem ratio, crude protein content, neutral detergent fiber content and acid detergent fiber content of the next two parts were all increased, and the relative feeding value were all increased, that is to say, the quality of the upper and lower parts had improved.
【学位授予单位】：北京林业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S541.9

【相似文献】