The effect of interval between harvests and nitrogen application on the digestibility and digestible yield and nitrogen content and yield of four ryegrass varieties in the first harvest year
The effect of interval between harvests and nitrogen application on the digestibility and digestible yield and nitrogen content and yield of four ryegrass varieties in the first harvest year
复制标题
采收间隔和施氮量对4个黑麦草品种第一年消化率、可消化产量及氮含量和产量的影响
DOI：
10.1017/s0021859600054861
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发表时间：
1976
期刊：
影响因子：
--
通讯作者：
J. Shim
中科院分区：
文献类型：
--
作者：
D. Wilman;D. Droushiotis;A. Koocheki;A. B. Lwoga;J. Shim
总结在田间试验中，在第一个收获年的30周期间，研究了6个收获间隔和3个氮肥水平对4个黑麦草品种消化率、可消化产量、氮含量和产量的影响。消化率较高，3周比收获之间的间隔较长。可消化有机物的产量增加的间隔从3至6周，但略有减少，从6至10周延长。施氮水平的增加增加了弯曲度向下的响应，以延长可消化有机质和氮产量的间隔，支持的观点，氮的使用应伴随着缩短收获之间的间隔。消化率变化高达15个单位的D值从一年中的一个时间到另一个收获之间的恒定间隔。最高值出现在春季。秋季值低，尽管绿色叶的比例相对较高。在紧接着茎发育的主要时期之后的时期内，将间隔从4周增加到8周或从5周增加到10周使消化率减少10个单位，并使可消化产量减少22%。在不施氮的情况下，S. 321比S. 22，S。23和S. 24.但S. 321远低于其他品种。
Summary The effect of six intervals between harvests and three levels of N application on digestibility, digestible yield and nitrogen content and yield was studied in four ryegrass(Lolium) varieties during a 30-week period in the first harvest year in a field experiment. Digestibility was higher with a 3-week than with a longer interval between harvests. Yield of digestible organic matter was increased by extending the interval from 3 to 6 weeks, but was slightly reduced by extending from 6 to 10 weeks. Increase in the level of applied N increased the degree of curvature downwards in the response to extending the interval in both yield of digestible organic matter and yield of N, supporting the view that N use should be accompanied by shortened intervals between harvests. Digestibility varied by up to 15 units D-value from one time of the year to another with a constant interval between harvests. The highest values were in the spring. Autumn values were low in spite of a relatively high proportion of green leaf. During the period immediately following the main period of stem development, doubling the interval from 4 to 8 or from 5 to 10 weeks reduced digestibility by 10 units and reduced digestible yield by 22%. In the absence of applied N, the N yield of S. 321 was 31% greater than the average of S. 22, S. 23 and S. 24. However, the apparent recovery of applied N in S. 321 was much lower than in the other varieties.