水稻拔节期叶片碳氮代谢基因型差异及与氮素利用效率的关系

 采用土培盆栽试验,以3个氮素利用效率(NUE)有显著差异的水稻基因型秀恢2号(低NUE)、R83 12(中NUE)和五优244(高NUE)为材料,研究了拔节期叶片碳氮代谢的基因型差异及其与氮素高效利用的关系。结果表明,拔节期不同基因型水稻的叶片蔗糖和可溶性糖含量、淀粉/可溶性糖含量比和淀粉/蔗糖含量比存在极显著差异,前两者为五优244 > R83 12 >秀恢2号,后两者则相反;而淀粉和蔗糖/可溶性糖含量比各基因型差异不显著。不同基因型水稻的叶片全氮含量(TNC)、蛋白氮含量(PNC)、 PNC/TNC、Rubisco含量(RC)/PNC和RC/TNC存在极显著或显著差异,前两者为五优244 < R83 12 <秀恢2号, 后三者则相反;RC无基因型差异。五优244叶片的叶绿素a含量、类胡萝卜素含量、PSⅡ潜在活性、羧化效率、碳酸酐酶、酸性转化酶和蔗糖磷酸合成酶活性极显著或显著高于其他基因型;其叶片的硝酸还原酶、谷氨酰胺合成酶、谷氨酸合成酶和谷氨酸脱氢酶活性也极显著高于其他基因型。统计分析表明,高NUE水稻叶片具有较高的可溶性糖和蔗糖含量及较大的RC/TNC和RC/PNC,其生理基础是其叶片的高谷氨酰胺合成酶活性和PSⅡ潜在活性。     

Influence of the cultivar,environment and management on the grain yield and bread-making quality in winter wheat

The genotype, environment and their interaction play an important role in the grain yielding and grain quality attributes. The main aim of this study was to determine the contributions of the genotype, environment and their interaction to the variation in bread-making traits. The data that were used for the analyses performed in this study were obtained from 3 locations in Poland from post-registration multi-environment trials with winter wheat in 2009 and 2010. The experimental factors were the cultivar (7 cultivars) and the crop management level (low input and high input). In the multi-environment trials, 17 traits were investigated that characterize grain, flour and dough quality. Most of the traits were affected much more strongly by environmental factors (i.e., year and location) than by genotype. The variance components revealed an especially strong effect of the year on the baking score, loaf volume and water absorption, as well a strong effect of the location on dough development and protein content. The obtained results demonstrate that the grain quality as measured by the parameters based on the protein content and quality may be substantially improved by crop management practices, especially by N fertilization level.     

Amelioration of saline–sodic soil with gypsum can increase yield and nitrogen use efficiency in rice–wheat cropping system

A 2-year field experiment was conducted to determine crop yield and N use efficiency (NUE) from a saline–sodic soil (clay loam) with and without application of gypsum. Treatments included two N application rates (15% and 30%) higher than the recommended one to the normal soil, and gypsum added at 50% and 100% of soil gypsum requirement (SGR) to the saline–sodic soil, both cultivated with rice and wheat during 2011–2013. Results revealed a decrease in pH of saturated soil paste (pH_s), electrical conductivity of saturation extract (EC_e), sodium adsorption ratio (SAR) and exchangeable sodium percentage with N fertilizer along with gypsum application in saline–sodic soil. However, the effect was most prominent when gypsum was added at 50% of SGR. Crop yield and NUE remained significantly lower (p < 0.05) in saline–sodic-soils as compared to normal soil. However, gypsum application reduced this difference from 47% to 17% since both yield and NUE increased considerably. Crop yield and NUE remained higher for wheat than for rice. During first year, higher doses of N with gypsum application at 50% SGR proved most effective, whereas, in subsequent year, recommended N along with gypsum at 50% SGR became more profitable. All these results lead us to conclude that gypsum application can ameliorate saline–sodic soil thereby increasing crop yield and NUE.     

施氮量对北疆滴灌春小麦-青贮玉米氮素利用率及土壤硝态氮的影响

【目的】研究新疆北疆滴灌春小麦-青贮玉米种植模式中土壤硝态氮分布规律。【方法】研究前茬春小麦选用新春6号、后茬青贮玉米选用新饲玉13号作为材料,其中前茬设置4个施氮处理(即纯氮量对照0.0、240.0、360.0、480.0 kg/hm²,用代码N_w0、N_w1、N_w2和N_w3表示),后茬设置4个施氮量处理(即对照0.0、225.0、337.5、450.0 kg/hm²,用代码N_c0、N_c1、N_c2和N_c3表示),并于前茬春小麦3个生育时期,后茬青贮玉米5个生育时期,分别取0~20、20~40和40~60 cm三个层次土样,用AA3连续流动分析仪测定土壤硝态氮含量。【结果】土壤硝态氮含量总体随着施氮量的增加而增加,随着生育期的推进先增加后减少,春小麦在开花期达到峰值,青贮玉米在吐丝期达到峰值,且前茬硝态氮残留量的增加对后茬土壤硝态氮含量有提高的作用;前后茬0~20、20~40和40~60 cm三个层次土壤硝态氮含量随着土层的加深而减少,随着施氮量的增加而增加,中、高施氮量(前茬360.0和480.0 kg/hm²,后茬337.5和450.0 kg/hm²)会促进土壤硝态氮向下层土移动。产量及产量构成因素上,前后茬均表现为:随着施氮量的增加,产量及构成因素先增加后减少,春小麦在360.0 kg/hm²施氮处理下产量最高,达6 713.39 t/hm²,青贮玉米在225.0 kg/hm²施氮处理下产量最高,达88.91 t/hm²(鲜重)。随着施氮量的增加,农学利用率和氮肥偏生产力逐渐降低。【结论】在北疆地区春小麦-青贮玉米种植模式下,采用前茬360.0 kg/hm²、后茬225.0 kg/hm²的施氮组合,有利于实现该种植模式的高产和氮素高效利用。     

Effects of types and application rates of nitrogen fertilizer on the development and nitrogen utilization of summer maize

To reduce nitrogen fertilizer (NF) loss and improve nitrogen use efficiency (NUE) in summer maize, the effects of the different application rates of three types of NF (urea, coated urea and compound fertilizer) on the growth and development and NUE of summer maize (cultivars: Zhengdan958 and Nongda108) were studied in 2004. The main findings of this study were: (1) The yields of the two cultivars increased significantly with each increment of N application rate from 0–180 kg N·hm⁻². The increase in the yield of summer maize treated with compound fertilizer was greater than the yield of those treated with either of the other two fertilizers at the same application rate, while the differences among the three types of NF were not significant. (2) Grain number per ear of the two cultivars rose in relation to the increase in N application rate, while its relationship with the type of NF was very weak. The type of NF had a greater impact on 1000-grain weight, and a difference between cultivars was observed. (3) Leaf area index (LAI), dry matter weight and leaf chlorophyll content grew in relation to the increase in N application rate, and were improved more sharply by compound fertilizer or coated urea than by urea alone. (4) Compared to the results achieved with urea, the NUEs of summer maize treated with coated urea and compound fertilizer were higher but the nitrogen harvest index was not improved. In addition, the NUEs of three types of NF exhibited a genotype difference from summer maize. __________ Translated from Acta Agriculturae Boreali-Sinica, 2006, 21(1): 115–120 [译自: 华北农学报]     

典型玉米自交系氮素吸收利用特点的研究

在大田条件下,对8个代表性的玉米自交系在不同施氮水平下的氮素吸收与利用特点及与氮效率相关的一些性状进行了研究。结果表明：玉米自交系在产量、生物量和氮累积量上存在显著的差异。通过玉米自交系各性状与氮效率的关系的分析表明,低氮胁迫下,应选择抽丝期穗位叶叶绿素含量高、穗位叶叶面积大、籽粒含氮量高和氮收获指数大的自交系,高氮处理条件下,应选择抽丝期生物量大和成熟期生物量大的自交系。通径分析表明,氮吸收和氮利用效率对氮效率的作用均是直接作用大于间接作用。3个施氮水平条件下,对氮效率的直接作用是氮吸收效率大于氮利用效率。在低氮条件下,氮吸收效率的直接作用更强,而氮利用效率对氮效率的直接作用是随着施氮量的增加逐渐增强。在氮2、氮3处理中,吸收效率和利用效率的共同影响导致了产量差异,并且是吸收效率的影响较大;高氮处理则主要是吸收效率的影响。     

氮肥施用时间和植物生长调节剂对小麦氮吸收和利用的影响

研究了氮肥施用时间和植物生长调节剂对小麦氮吸收和利用的影响。结果表明,氮肥施用时间和植物生长调节剂对小麦植株氮含量、积累和利用有显著影响。烯效唑 (S₃₃₀₇)和GA₃处理均能增加植株的氮含量,二者又以GA₃处理的效果更为明显。S₃₃₀₇和GA₃混合使用能明显提高各生育期的氮含量。植株氮含量在基因型之间差异显著,孕穗期叶片和茎杆扬麦5号显著高于浙农大941,而成熟期则以浙农大941较高。S₃₃₀₇由于抑制干物质合成而减少了氮的积累,而GA₃则增加氮的积累并减轻S₃₃₀₇的抑制作用。氮利用效率(NUE)和氮效率比(NER)在基因型和不同植物生长剂处理之间存在着显著差异。扬麦5号的NUE和NER高于浙农大941。与S₃₃₀₇或GA₃单独使用相比,两种生长调节剂混合应用显著增加了NUE和NER。     

典型玉米自交系氮素吸收利用特点的研究

在大田条件下,对8个代表性的玉米自交系在不同施氮水平下的氮素吸收与利用特点及与氮效率相关的一些性状进行了研究。结果表明:玉米自交系在产量、生物量和氮累积量上存在显著的差异。通过玉米自交系各性状与氮效率的关系的分析表明,低氮胁迫下,应选择抽丝期穗位叶叶绿素含量高、穗位叶叶面积大、籽粒含氮量高和氮收获指数大的自交系,高氮处理条件下,应选择抽丝期生物量大和成熟期生物量大的自交系。通径分析表明,氮吸收和氮利用效率对氮效率的作用均是直接作用大于间接作用。3个施氮水平条件下,对氮效率的直接作用是氮吸收效率大于氮利用效率。在低氮条件下,氮吸收效率的直接作用更强,而氮利用效率对氮效率的直接作用是随着施氮量的增加逐渐增强。在氮2、氮3处理中,吸收效率和利用效率的共同影响导致了产量差异,并且是吸收效率的影响较大;高氮处理则主要是吸收效率的影响。     

Assessing the effects of urea and nano-nitrogen chelate fertilizers on sugarcane yield and dynamic of nitrate in soil

ABSTRACT

The aim of this study was to evaluate the effect of urea and Nano-Nitrogen Chelate (NNC) fertilizers on yield of sugarcane (Saccharum Officinarum) and nitrate leaching from soil. The treatments included urea (U) and NNC at five levels of nitrogen (0, 80, 112, 137 and 161 kg N ha^?1). This experiment was carried out during 2017 and 2018 in Khuzestan province, Iran. The results showed that the average of soil nitrate concentration during the sugarcane growth period in urea and NNC treatments were 10.2 and 12.8 mg kg^?1 respectively. The highest and lowest nitrate leaching (699.0 mg l^?1 and 183.0 mg l^?1) belongs to the highest level of urea fertilizer and the lowest level of NNC. In urea treatments, the lowest amount of nitrate was observed in the topsoil (0-30 cm depth) whereas in NNC fertilizer maximum value was achieved in topsoil. The height of sugarcane stem in both fertilizers increased with increasing rate of fertilizer, but there was no significant difference between two types of fertilizer. Yield of sugarcane (fresh weight of stem) increased significantly by increasing of fertilizer application, but there was no significant difference between two types of fertilizer. In terms of sugar content, there was a significant difference between treatments. The order of nitrogen use efficiency (NUE) for stems and sugar yield from high to low was as NUE (fresh stem): U₁ > N₁ > N₃ ≥ U₃ ~ U₂ > N₄ ~ U₄ > N₂ and for NUE (sugar): N₁ > U₁ > N₃ ≥ N₂ > U₂ ~ N₄ ≥ U₃ > U₄. This study showed that application of nano nitrogen fertilizer (NNC) had significant effects on reducing nitrate leaching and increasing sugar production in sugarcane. However, when nitrate leaching and its effects on human health and the environment are in view, nano fertilizers are valuable.     

Comparison of Five Nitrogen Dressing Methods to Optimize Rice Growth

Abstract

The applicability of five nitrogen (N) dressing methods to rice cultivation was examined using the canopy spectrum-based nitrogen optimization algorithm (CSNOA), leaf area index (LAI), site-specific N management (SSNM), N nutrition index (NNI), and N fertilizer optimization algorithm (NFOA). After base-tiller N dressing (basal dressing and top dressing at the tillering stage) at low and normal levels, rice plants were grown by the above five N dressing methods. The effects of different N dressing methods on plant dry weight, plant N accumulation, grain yield, N use efficiency, and economic benefit were analyzed. Compared with the standard method, under the low base-tiller N dressing level, the optimum N dressing rate was decreased, and the economic benefit was increased by adapting the N dressing methods of CSNOA and SSNM, whereas the optimum N dressing rate was increased, and the economic benefit was decreased by the other three N dressing methods. Under the general base-tiller N dressing level, the optimum N rate, N-use efficiency and economic benefit were increased by all N dressing methods except the NFOA. These results indicated that the CSNOA and SSNM were two good techniques for quantifying N dressing in rice, with higher economic benefit, less N input, and better applicability under different base-tiller N dressing levels.