【作者】 刘波；

【导师】 孙启忠；

【作者基本信息】 中国农业科学院 ， 草业科学， 2008， 硕士

【摘要】 本研究主要对新麦草种子生产不同时期的管理技术进行了较为系统深入的研究,对不同因素导致的新麦草种子产量变化进行了分析,为今后该领域进一步细化的研究工作奠定了试验基础,为新麦草种子生产提供了理论和试验上的依据。本研究主要取得以下结果:1.氮肥对新麦草种子产量具有显著影响。随着氮肥施用量的增加,新麦草种子产量增加显著。种子产量在所设计的14个施氮量中分为三个区间,在总施肥量0～200 kgN/hm~2的区间内,产量最高的是50 kgN/hm~2(早秋)+50 kgN/hm~2(晚秋)+100 kgN/hm~2(早春)的施肥处理,这个区间基本遵循了产量与总施氮肥量成正比的规律。在总施肥量为250 kgN/hm~2的不同组合中,获得最高种子产量的是50 kgN/hm~2(早秋)+100kgN /hm~2(晚秋)+100 kgN/hm~2(早春)处理,达到1425.0kg/hm~2;产量最低的是对照0 kgN/hm~2(早秋)+0 kgN/hm~2(晚秋)+0 kgN/hm~2(早春)处理。均匀施用氮肥可提高新麦草种子产量,在同一个时期施用大量氮肥不仅起不到增产作用,并且会使产量降低。如0 kgN/hm~2(早秋)+0 kgN/hm~2(晚秋)+250 kgN/hm~2(早春)处理最终产量只有700.9kg/hm~2,而250 kgN/hm~2(早秋)+0 kgN/hm~2(晚秋)+0 kgN/hm~2(早春)只有973.1kg/hm~2。在总施肥量大于250 kg N/hm~2的不同处理中,实际种子产量有较大幅度的增加,但未超过250 kg N/hm~2的最大产量,而且它们彼此之间差异也不显著。2.不同收获时期对新麦草种子的产量和质量显著影响。试验证明,在新麦草收获期随着种子含水量的下降,产量先增加后降低,最高产量出现在盛花期后第24d收获的种子中,其含水量为35%左右,产量可达2250.0kg/hm~2。而从标准发芽率和控制劣变发芽的情况可知,新麦草种子质量的高峰出现在盛花期后第21d之后,即种子含水量为40%～10%之间,控制劣变发芽率和标准芽率峰值分别出现在盛花期后第24d和27d采收的新麦草种子中,分别达到96.5%和99%。3.试验通过不同的新麦草种子收获方式:完全收获、人工收割草条和康拜因收获,从而发现康拜因机械收获比起人工草条收获效率有较大提高,在新麦草、高羊茅、扁穗冰草的收获产量上两种收获方式差异显著,康拜因机械收获可将单产分别提高385.1kg/hm~2,66.8kg/hm~2,275.0kg/hm~2,但是距种子的完全收获量还有较大差距。同时试验利用两种清选方式即机械清选和人工清选,对机械收获的种子样品进行清选,确定了最佳清选方式。4.本试验表明在新麦草种子收获后以不同残茬处理方式清理地面残茬均可以起到增加枝条密度,提高种子产量的效果。其中以冬季放牧+春季火烧效果最佳。其返青期、拔节期分蘖数分别达到1160.75个/m~2和1728个/m~2,生殖枝数为667个/m~2,种子实际产量达到1253.85kg/hm~2,分别比对照高出327%和493%。更多还原

【Abstract】 This article is about the systemic research of optimization management of Russian Wildrye in its different seasons and the analysis of different factors which lead to its yield changed. The experimentations provide theory basis for the further research and the seed production of Russian Wildrye. These are the results of the experimentations:1.The nitrogen application: There are considerable effects of the nitrogen for Russian Wildrye. The seed yield is increased remarkably with a more nitrogen concentration. The seed yield which come from 14 different treatments can be classified three parts. The first is the nitrogen concentration zone is 0～200 kg N/hm~2. The highest seed yield come from the treatment of 50 kg N/hm~2(fall)+50 kg N/hm~2(later fall)+100 kgN/hm(2spring),the yield is 1383.3 kg/hm~2.Basicly, yield is direct proportion with nitrogen concentration In this zone. The second part is 250 Nkg/hm~2 zone, the most yield is 1425.0 kg/hm~2, from the treatment of 50 kg N/hm~2(fall)+100 kg N/hm~2(later fall)+100 kg N/hm~2(spring)and the least yield is 700.9 kg/hm~2 from the treatment of 0 kg N/hm~2(fall)+0 kg N/hm~2(later fall)+0kg N/hm~2(spring).The experimentation shows that the seed yield increases when the nitrogen is used in different time with some proportion but decreases when mass nitrogen is used in the same time as 0 kg N/hm~2(fall)+0 kg N/hm~2(later fall)+250 kg N/hm~2(spring)and 250 kg N/hm~2(fall)+0 kg N/hm~2(later fall)+0 kg N/hm~2(spring)for example. The third part which the nitrogen concentration is up the 250 kg/hm~2, the seed yield is increased indistinctive compared with the most yield, 1425.0 kg/hm~2.3. The effect of harvest time for the seed yield and its quality. The seed yield and quality is different significantly in different harvest time. It shows that the seed yield is up then down with the seed moisture content is down. The greatest yield is 2250kg/hm~2 at 24d after peak anthesis, the moisture content is 31%.The greatest quality seeds is harvested in 24d~27d after peak anthesis and their moisture content is 40%~10%, and their accelerate aging determination and determination are 96.5% and 99%.2. The effect of different harvest ways and electing ways for the seed yield. There are 3 ways for 4 kinds of seed: whole harvesting, bundling by people and combine harvesting .It shows that combine harvesting is more effective than bundling by people. The yield increase 385.1kg/hm~2, 66.8kg/hm~2 and 275.0kg/hm~2 for Russia Wildrye, Festuca and Agropyron cristatum with combine than bundling by people, but it is fewer than the whole harvesting way. There are 2 electing ways: pipelining and manpower. The result shows that pipelining is better.4.Dispose the crop residue : Because of changing the effect of photosynthesis of the base of plant, the number of the segregate and of the product tress will be increased through the treatments for the crop residue. It shows that density of the plant and seed yield will be changed in different ways to deal with the crop residue after harvesting. The yield of“winter grazing+ spring burning”is greatest ,it has the most segregates (1160.75/m~2 in regreen time,1728/m~2 in jointing)、the most production tresses(667/m~2)and the greatest yield (1253.85kg/hm~2).The production stress and yield of the“winter grazing+ spring burning”has more 327% and 493% than the control’s. Their difference is significant(P<0.05).更多还原