摘要:生态化学计量学是研究生态系统能量平衡和多重化学元素平衡的科学，可利用植物体内C、N和P含量及其相互比值（N：P、C：N和C：P，即生态化学计量比）来判断植物生长过程中营养的供给状况。本文通过研究小麦叶片主要元素的生态化学计量比对不同土壤N、P状况的响应，为小麦生产中的精确施肥提供技术指导。选取研究区当家品种弱筋小麦‘扬麦15’和强筋小麦‘镇麦168’为试验对象，采用盆栽试验，设置16个土壤N、P梯度处理，分析不同处理下小麦拔节期、孕穗期和灌浆期叶片N：P、C：N和C：P等生态化学计量比及其相互关系。结果表明：1）在拔节期和孕穗期，土壤N：P范围在7.04~8.73时，两小麦品种叶片的N：P均达到较高水平；而在灌浆期，土壤N：P范围在8.73~10.42时，两小麦叶片的N：P均达较高水平。且小麦叶片N：P与土壤N：P具有极显著的正相关关系，但其相关性随着生育期的推进逐渐降低。2）当土壤处于低N水平时（108.4 mg·kg-1），两小麦品种叶片C：N均达较高水平，且其与土壤N：P呈显著负相关，即随着土壤N：P比率增大，小麦叶片中C：N呈减小的趋势。3）当土壤处于低P水平时（29.6 mg·kg-1），两小麦品种叶片C：P达较高水平，且其与土壤P含量呈极显著负相关，即随土壤中P的增加，小麦叶片中C：P均呈减小趋势。以上结果表明，土壤中N和P的不同供应水平显著改变不同品种小麦叶片的生态化学计量比，因此，具有稳态特性的生态化学计量比可作为小麦生产中养分调控的重要参照指标并加以应用。
关键词:生态化学计量/
小麦叶片/
生育期/
土壤氮磷
Abstract:Ecological stoichiometry is a science that studies the balance of energy and multiple chemical elements in the ecosystem. The contents of C, N and P and the related ecological stoichiometric ratios (N:P, C:N and C:P) in plants can be used to judge the level of nutrient supply during plant growth period. In this paper, a technical guidance for precise fertilization in wheat production was provided by determining the response of ecological stoichiometry of major elements in wheat leaf to different soil nitrogen and phosphorus conditions. The weak gluten wheat variety 'Yangmai 15' and strong gluten wheat variety 'Zhenmai 168' that were widely cultivated in the study area were selected as test materials. Using pot experiment, 16 treatments of different nitrogen and phosphorus gradients were set up and the ecological stoichiometric ratios of N:P, C:N and C:P at jointing, booting and grain-filling stages analyzed for different treatments. The results showed that:1) at jointing and booting stages, when soil N:P was 7.04-8.73, N:P of the two wheat varieties leaves were higher. At grain-filling stage when soil N:P was 8.73-10.42, N:P of the two wheat varieties was higher. There was significant positive correlation between N:P in wheat leaf and N:P in soil, but the correlation became weaker with wheat growth. 2) At a low soil N level (108.4 mg·kg-1), leaf C:N of the two wheat varieties was at a higher level. There was a significant negative correlation between C:N in wheat leaf and N:P in soil indicating that C:N in wheat leaf decreased with increasing of N:P in soil. 3) At low soil P level (29.6 mg·kg-1), C:P of the two wheat varieties leaves were higher as well. There was extremely significant negative correlation between C:P in wheat leaf and P content of soil, which suggested that C:P in wheat leaf decreased with increasing soil P content. The above results indicated that different supply levels of N and P in soil significantly changed leaf ecological stoichiometric ratios of different wheat varieties. Therefore, the steady-state characteristics of ecological stoichiometric ratio can be used as an important reference indicator for nutrient regulation in wheat production.
Key words:Ecological stoichiometry/
Wheat leaf/
Growth stage/
Soil nitrogen and phosphorus
PDF全文下载地址:
http://www.ecoagri.ac.cn/article/exportPdf?id=af75e213-01d6-45a6-bab4-24248604c735
