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71.
[目的]氮肥在农业中占有重要的地位,因此植物氮素的营养学研究日益受到重视。了解稳定性~(15)N示踪技术应用于氮素的分配、积累及氮素利用率情况。了解稳定性~(15)N示踪技术在农业氮肥利用中的应用,为提高氮肥利用率、实现生态农业可持续发展提供必要的理论支持。[方法]利用文献资料概述稳定性~(15)N示踪技术在小麦、水稻、烟草、果树、豆科作物上的应用,着重论述氮素吸收、利用、分配的研究现状。[结果]稳定性~(15)N示踪技术是研究氮素营养吸收规律的一种方便、快捷、灵活的方法之一,在科学施肥、植物营养、农用化学物质残留等农业方面已被广泛应用。[结论]今后,应将稳定性~(15)N示踪技术应将更多的应用到农业、环境、生物食品学领域,拓宽稳定性同位素的应用范围,并建立和完善相关的同位素定量化解析模型,提高测定位同位素的准确性。 相似文献
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炔草酯的控草效果和对油菜田间光照、养分、水分及 产量的影响 总被引:1,自引:2,他引:1
为明确15%炔草酯WP在油菜田的应用前景,建立油菜田的杂草管理体系,研究了不同开沟深度、不同时期施用15%炔草酯WP对油菜田杂草的控制作用以及炔草酯与其他药剂混用的效果,同时研究了该药剂对田间光照、养分、水分和油菜产量的影响。结果表明,开深沟有利于药效的发挥。在禾本科杂草处于1~2叶期时进行药剂处理,一般可以获得比较理想的除草效果。炔草酯与草除灵混用对禾本科杂草和双子叶杂草都具有良好的防除效果。施用15%炔草酯WP能显著提高油菜田间的透光率,降低杂草对田间养分和水分的吸收。15%炔草酯WP的施用对油菜株高、千粒重没有显著影响,但对油菜第一分枝高度、单株分枝数、角果数影响较大,能显著提高油菜产量。 相似文献
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Kai Fan Qunfeng Zhang Dandan Tang Yuanzhi Shi Lifeng Ma Meiya Liu Jianyun Ruan 《植物养料与土壤学杂志》2020,183(2):180-191
The contribution of N remobilization is crucial for new shoots growth and quality formation during spring tea shoots development. However, the translocation mechanism of N from source leaves to sink young shoots is not well understood. In the present study, 15N urea was applied to mature tea leaves one week before bud break to track N remobilization in a field experiment. The dynamic changes in plant 15N abundance, contents of amino acids, and the expression levels of genes related to N metabolism and translocation were followed during the 18‐d development of new spring shoots until three expanding young leaves. The results showed that during the growth of new shoots the amount of 15N in the shoots increased, whereas the Ndff (N derived from 15N‐urea) in mature leaves decreased, showing that the foliar‐applied N in mature leaves was readily exported to new shoots. This process was found to be accompanied by decline of chlorophylls. In the mature leaves, expression CsATG18a and CsSAG12 involved in autophagy was dramatically induced (> 4‐fold) at approximately nine days after the bud breaking. The genes involved in the transformation of amino acids, including primarily CsGDH2, CsGDH4, CsGLT3, CsGS1;3, and CsASN2 were upregulated by > 3‐fold after bud breaking. The expression levels of CsATG8A, CsATG9, CsSAG12, CsGS1;1, CsGDH1, and CsAAP6 correlated negatively with the Ndff in mature leaves, but positively with 15N amount and total N amount in new shoots, suggesting these genes played important roles in N export from mature leaves. In the new shoots, the expression of most genes showed two defined peaks, one on six days and one on 12 days after bud breaking. The expression of CsGS2, CsASN3, CsGLT1, and CsAAP4 positively correlated with the 15N amount and total N amount in new shoots. These genes might be involved in the transport and re‐assimilation of N from mature leaves. The overall results demonstrated that the translocation of 15N from mature leaves to new spring shoots was regulated by the genes involved in autophagy, protein degradation, amino acid transformation and transport. 相似文献
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基于15N示踪技术的干旱区滴灌葡萄氮素利用分析 总被引:1,自引:0,他引:1
为研究水氮调控对干旱区滴灌葡萄氮素吸收利用的影响,以新疆鲜食葡萄弗雷为试验材料,利用15N 示踪技术,设置2种灌水处理(灌水量为4 950、5 400 m3·hm-2,分别记作W1、W2),3种施氮处理(施氮量为177、235、292 kg·hm-2,分别记作F1、F2、F3)进行大田试验。结果表明,各处理土壤全氮含量和15N丰度差异极显著(P<0.01),并且在0~20 cm土层出现富集现象。各器官征调氮素能力随水氮投入加大极显著增强(P<0.01)。根系、茎秆、叶片器官的生物量随着吸氮量的增加极显著提高(P<0.01),而较高施氮量(F3)不利于果实器官生物量的积累。果树吸收的肥料氮量随水氮投入的加大逐渐增加,受水氮调控影响极显著(P<0.01),果树吸收的土壤氮量大于肥料氮量。W2F1的15N标记氮肥利用率和15N标记氮肥偏生产力最高,分别为38.36%和114.20 kg·kg-1,W2F2的产量最高,为20 253 kg·hm-2,但与W2F1差异不显著。表明水氮投入过多会引起茎秆和叶片器官徒长且不利于提高15N标记氮肥利用率。综上所述,灌水量5 400 m3·hm-2、施氮量177 kg·hm-2(W2F1)是兼顾经济效益与生态效应的可行水氮运筹模式。本研究结果为干旱区滴灌葡萄高产高效种植提供了参考。 相似文献
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Dong Wang Zhenzhu Xu Junye Zhao Yuefu Wang 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(8):681-692
Abstract Excessive use of nitrogen (N) fertilizers in wheat fields has led to elevated NO3-N concentrations in groundwater and reduced N use efficiency. Three-year field and 15N tracing experiments were conducted to investigate the effects of N application rates on N uptake from basal and topdressing 15N, N use efficiency, and grain yield in winter wheat plants; and determine the dynamics of N derived from both basal and topdressing 15N in soil in high-yielding fields. The results showed that 69.5–84.5% of N accumulated in wheat plants derived from soil, while 6.0–12.5%and 9.2–18.1% derived from basal 15N and top 15N fertilizer, respectively. The basal N fertilizer recovery averaged 33.9% in plants, residual averaged 59.2% in 0–200 cm depth soil; the topdressing N fertilizer recovery averaged 50.5% in plants, residual averaged 48.2% in 0–200 cm soil. More top 15N was accumulated in plants and more remained in 0–100 cm soil rather than in 100–200 cm soil at maturity, compared with the basal 15N. However, during the period from pre-sowing to pre-wintering, the soil nitrate moved down to deeper layers, and most accumulated in the layers below 140 cm. With an increase of N fertilizer rate, the proportion of the N derived from soil in plants decreased, but that derived from basal and topdressing fertilizer increased; the proportion of basal and top 15N recovery in plants decreased, and that of residual in soil increased. A moderate application rate of 96–168 kg N ha?1 led to increases in nitrate content in 0–60 cm soil layer, N uptake amount, grain yield and apparent recovery fraction of applied fertilizer N in wheat. Applying above 240 kg N ha?1 promoted the downward movement of basal and top 15N and soil nitrate, but had no significant effect on N uptake amount; the excessive N application also obviously decreased the grain yield, N uptake efficiency, apparent recovery fraction of applied fertilizer N, physiological efficiency and internal N use efficiency. It is suggested that the appropriate application rate of nitrogen on a high-yielding wheat field was 96–168 kg N ha?1. 相似文献