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1.
密度、 氮肥对玉米杂交种节根数量的影响 总被引:2,自引:0,他引:2
【目的】玉米地上和地下茎节生长的节根分别被定义为地上节根(气生根)和地下节根; 地上和地下节根在玉米生长全生育期的水分、 养分吸收以及抗倒伏方面起重要作用。密度和氮肥施用是作物生长和高产最为关键的两个农学影响因子,研究高产密植栽培中氮素如何影响玉米地上及地下节根数的变化,可为选择适宜的品种提供依据。【方法】以玉米自交系GEMS30、 Zheng653、 Mo17、 B73、 CIMBL153为母本,以武312(Wu312)及其近等基因系为父本组配的10对测交组合为试验材料,在2个密度水平(60000和80040 plant/hm2)和3个氮水平(0、 120和240 kg/hm2)下,通过田间挖根,然后按照玉米生长的轮次逐一割下节根并记录数量,同时利用NK-100型数显式弹簧拉力计测定地上第3节位的抗倒拉力。研究总节根数、 地上节根数(气生根)、 地下节根数、 茎秆抗倒拉力和产量的变化规律及其相互关系。【结果】本研究条件下,高密度显著降低产量; 供氮水平也显著影响产量,N 120 kg/hm2时产量高于N 0和240 kg/hm2。地上节根和地下节根数均受氮肥、 密度及氮肥密度互作的显著影响。高密种植平均使地上节根数减少3~6条,而地下节根数量不受影响; 抗倒拉力降低14%~29%,但是在N 240 kg/hm2条件下,高密度对地上和地下节根数的影响不显著。在N 120 kg/hm2供应条件下的地上和地下节根数、 抗倒拉力均高于不施氮,低密度下玉米地上节根数也高于N 240 kg/hm2。不同杂交种的地上节根对氮和密度的响应存在显著差异,其中以B73为母本的2个基因型最为敏感。相关分析表明,在N 0和N 120 kg/hm2条件下,无论密度高低,地下节根数与产量都呈显著正相关; 在低密度下N 0和N 120 kg /hm2条件下, 地下节根数与抗倒拉力呈显著正相关。但高密度在N0下,地上节根数与产量呈显著负相关。【结论】在适宜栽培条件下,地下和地上节根数量多,抗倒能力强,产量高,地下节根数对产量和抗倒伏的贡献相对更为重要。在胁迫条件下,过多的地上节根数可能对产量形成起负作用。因此,根据目标产量,在适宜栽培条件下,选择地下节根数多的品种可以提高产量和抗倒伏率。 相似文献
2.
Christos Noulas Juan M. Herrera Ioannis Alexiou Theodore Karyotis Markus Liedgens Peter Stamp 《Journal of plant nutrition》2014,37(7):1012-1024
Efficient use of nitrogen (N) by wheat crop and hence prevention of possible contamination of ground and surface waters by nitrates has aroused environmental concerns. The present study was conducted in drainage lysimeters for three years (1998–2000) to identify whether spring wheat genotypes (Triticum aestivum L.) that differ in N-related traits differ in N leaching and to relate parameters of N use efficiency (NUE) with parameters of N leaching. For this reason two spring wheat cultivars (‘Albis’ and ‘Toronit’) and an experimental line (‘L94491’) were grown under low (20 kg N ha?1) and ample N supply (270 kg N ha?1). The genotypes varied in parameters of NUE but not in N leaching. Grain yield of the high-protein line (‘L94491’) was, on average, 11% lower than that of ‘Toronit’ but among genotypes had significantly higher N in the grain (%), grain N yield, and N harvest index. Nitrogen lost through leaching was considerably low (0.42–0.52 g m?2) mainly due to low volume of percolating water or the ability of the genotypes to efficiently exploit soil mineral N. There were no clear relationships between N-related genotype traits and N leaching, but across all treatments significantly negative correlations between volume of leachate and the amount of N in the total biomass and grain N yield existed. 相似文献
3.
Hani Saber Saudy Mohamed Fawzy Hamed Wasfi Ramadan Abd El-Momen Hossam Hussein 《Communications in Soil Science and Plant Analysis》2020,51(8):1036-1047
ABSTRACT Integrated management of soil organic matter and nutritional status of crop plants is essential to sustain the production of organic farming systems. Thus, a 2–year field experiment was conducted to examine the effects of soil additions (192 kg N ha–1, humic+192 kg N ha–1, humic+144 kg N ha–1 and humic+96 kg N ha–1) and foliar applications (amino acids, Azotobacter+yeast, and amino acids plus Azotobacter+yeast) as various fertilizer resources on growth and yield of wheat. Results showed that humic+192 kg N ha–1 × amino acids plus Azotobacter+yeast were the effective combination for producing the highest values of flag leaf area, total dry weight, tiller number m–2, spike weight m–2, and grain yield ha–1. Under foliar application of amino acids plus Azotobacter+yeast, reducing N supply from recommended rate (192 kg N ha–1) to 144 kg N ha–1+ humic achieved higher values of all yield traits, with a saving of 25% of applied mineral nitrogen as well as enhancing nitrogen use efficiency. 相似文献
4.
The availability of nitrogen (N) contained in crop residues for a following crop may vary with cultivar, depending on root traits and the interaction between roots and soil. We used a pot experiment to investigate the effects of six spring wheat (Triticum aestivum L.) cultivars (three old varieties introduced before mid last century and three modern varieties) and N fertilization on the ability of wheat to acquire N from maize (Zea mays L.) straw added to soil. Wheat was grown in a soil where 15N‐labeled maize straw had been incorporated with or without N fertilization. Higher grain yield in three modern and one old cultivar was ascribed to preferred allocation of photosynthate to aboveground plant parts and from vegetative organs to grains. Root biomass, root length density and root surface area were all smaller in modern than in old cultivars at both anthesis and maturity. Root mean diameter was generally similar between modern and old cultivars at anthesis but was greater in modern than in old cultivars at maturity. There were cultivar differences in N uptake from incorporated maize straw and the other N sources (soil and fertilizer). However, these differences were not related to variation in the measured root parameters among the six cultivars. At anthesis, total N uptake efficiencies by roots (total N uptake per root weight or root length) were greater in modern than in old cultivars within each fertilization level. At maturity, averaged over fertilization levels, the total N uptake efficiencies by roots were 292?336 mg N g?1 roots or 3.2?4.0 mg N m?1 roots for three modern cultivars, in contrast to 132?213 mg N g?1 roots or 0.93?1.6 mg N m?1 roots for three old cultivars. Fertilization enhanced the utilization of N from maize straw by all cultivars, but root N uptake efficiencies were less affected. We concluded that modern spring wheat cultivars had higher root N uptake efficiency than old cultivars. 相似文献
5.
Haoru Li Weiping Hao Qi Liu Lili Mao Vinay Nangia Rui Guo Xurong Mei 《植物养料与土壤学杂志》2019,182(3):335-346
The intensive winter wheat (Triticum aestivum L.)–summer maize (Zea mays L.) cropping systems in the North China Plain (NCP) rely on the heavy use of mineral nitrogen (N) fertilizers. As the fertigated area of wheat and maize in the NCP has grown rapidly during recent years, developing N management strategies is required for sustainable wheat and maize production. Field experiments were conducted in Hebei Province during three consecutive growth seasons in 2012–2015 to assess the influence of different N fertigation rates on N uptake, yield, and nitrogen use efficiency [NUE: recovery efficiency (REN) and agronomic efficiency (AEN)]. Five levels of N application, 0 (FN0), 40 (FN40%), 70 (FN70%), 100 (FN100%), and 130% (FN130%) of the farmer practice rate (FP: 250 kg N ha?1 and 205.5 kg N ha?1 for wheat and maize, respectively), corresponding to 0, 182.2, 318.9, 455.5, and 592.2 kg N ha?1 y?1, respectively, were tested. Nitrogen in the form of urea was dissolved in irrigation water and split into six and four applications for wheat and maize, respectively. In addition, the treatment “drip irrigation + 100% N conventional broadcasting” (DN100%) was also conducted. All treatments were arranged in a randomized complete block design with three replications. The results revealed the significant influence of both N fertigation rate and N application method on grain yield and NUE. Compared to DN100%, FN100% significantly increased the 3‐year averaged N recovery efficiency (REN) by 0.09 kg kg?1 and 0.04 kg kg?1, and the 3‐year averaged N agronomic efficiency (AEN) by 2.43 kg kg?1 and 1.62 kg kg?1 for wheat and maize, respectively. Among N fertigation rates, there was no significant increase in grain yield in response to N applied at a greater rate than 70% of FP due to excess N accumulation in vegetative tissues. Compared to FN70%, FN100%, and FN130%, FN40% increased the REN by 0.17–0.57 kg kg?1 and 0.03–0.34 kg kg?1and the AEN by 4.60–27.56 kg kg?1 and 2.40–10.62 kg kg?1 for wheat and maize, respectively. Based on a linear‐response relationship between the N fertigation rate and grain yield over three rotational periods it can be concluded that recommended N rates under drip fertigation with optimum split applications can be reduced to 46% (114.6 kg N ha?1) and 58% (116.6 kg N ha?1) of FP for wheat and maize, respectively, without negatively affecting grain yield, thereby increasing NUE. 相似文献
6.
Subsoil acidity restricts root growth and reduces crop yields in many parts of the world. More than half of the fertilizer nitrogen(N) applied in crop production is currently lost to the environment. This study aimed to investigate the effect of gypsum application on the efficiency of N fertilizer in no-till corn(Zea mays L.) production in southern Brazil. A field experiment examined the effects of surface-applied gypsum(0, 5, 10, and 15 Mg ha~(-1)) and top-dressed ammonium nitrate(NH_4NO_3)(60, 120, and 180 kg N ha~(-1)) on corn root length, N uptake, and grain yield. A greenhouse experiment was conducted using undisturbed soil columns collected from the field experiment site to evaluate NO_3-N leaching, N uptake, and root length with surface-applied gypsum(0 and 10 Mg ha~(-1)) and top-dressed NH_4NO_3(0 and 180 kg N ha~(-1)). Amelioration of subsoil acidity due to gypsum application increased corn root growth,N uptake, grain yield, and N use efficiency. Applying gypsum to the soil surface increased corn grain yield by 19%–38% and partial factor productivity of N(PFPN) by 27%–38%, depending on the N application rate. Results of the undisturbed soil column greenhouse experiment showed that improvement of N use efficiency by gypsum application was due to the higher N uptake from NO_3-N in the subsoil as a result of increased corn root length. Our results suggest that ameliorating subsoil acidity with gypsum in a no-till corn system could increase N use efficiency, improve grain yield, and reduce environmental risks due to NO_3-N leaching. 相似文献
7.
Single plant traits such as green biomass, spike dry weight, biomass, and nitrogen (N) transfer to grains are important traits for final grain yield. However, methods to assess these traits are laborious and expensive. Spectral reflectance measurements allow researchers to assess cultivar differences of yield‐related plant traits and translocation parameters that are affected by varying amounts of available N. In a field experiment, six high‐yielding wheat cultivars were grown with N supplies of 0, 100, 160, and 220 kg N ha–1. Wheat canopies were observed spectrally throughout the grain‐filling period, and three spectral parameters were calculated. To describe the development of the vegetative plant parts (leaves + culms) and the spikes, plants were sampled four times during grain filling. Dry weights and the relative dry‐matter content were recorded for leaves + culms and spikes. The N status of the plants was assessed by measuring the total N concentration and by calculating the aboveground N uptake. Good correlations were found between spectral indices and single plant traits throughout grain filling but varied with N supply and development stage. The normalized difference vegetation index, NDVI, was strongly affected by the saturation effects of increased N concentration. The red‐edge inflection point, REIP, predicted plant traits with r2 values up to 0.98. However, in plants with advanced senescence, the REIP was less efficient in describing plant traits. The NIR‐based index R760/R730 was closely related to yield‐related plant traits at early grain filling. Compared to the REIP, the R760/R730 index was resistant to strong chlorophyll decays being able to predict plant traits at late grain filling, with r2 values of up to 0.92. Spectral reflectance measurements may represent a promising tool to assess phenotypic differences in yield‐related plant traits during grain filling. 相似文献
8.
Yesuf Assen Mohammed Jonathan Kelly Bee Khim Chim Emily Rutto Kevin Waldschmidt Jeremiah Mullock 《Journal of plant nutrition》2013,36(5):749-761
From 2002 to date, a long-term field experiment has been conducted at Lake Carl Blackwell, Oklahoma, with different rates and times of nitrogen (N) fertilizer application to determine their effect on grain yield, protein and N uptake of winter wheat. Trend analysis for N rates (0, 50, 100, 150 and 200 kg N ha?1) and orthogonal contrasts for different application times (pre-plant, top-dressed in February and March) were performed. With increasing fertilizer N, wheat grain yield and protein content increased from 2110 kg ha?1 to 6783 kg ha?1 and from 8.96 to 17.19%, respectively. For grain yield, protein, and N use efficiency, split applications of N fertilizer were much more efficient than applying all N pre-plant. Large differences in grain yields were noted for different years at the same N rate (range exceeded 5.0 Mg ha?1) and that illustrated the need for making within-year-specific N rate recommendations. 相似文献
9.
小麦根蘖发育和产量对耕作和追氮方式以及施氮量的响应 总被引:3,自引:2,他引:1
10.
Christos Noulas Juan M. Herrera Miltiadis Tziouvalekas Ruijun Qin 《Communications in Soil Science and Plant Analysis》2018,49(7):763-781
Four spring wheat genotypes (Triticum aestivum L.) were grown without (N0 = 0 kg N ha?1) and under ample (N1 = 250 kg ha?1) nitrogen (N) fertilizer in field experiments in two seasons. The aim was to assess genotypic variation in N use efficiency (NUE) components and N-related indices during grain filling thus to identify superior wheat genotypes. Leaf chlorophyll (SPAD) readings at crucial growth stages were employed to help differentiate genotypes. Interrelations between yield and N-related indices with SPAD, where also assessed to explain possible pathways of improving NUE early in the growing season. Results showed that genotypic effects on NUE were mostly evident in 2000, a year with drier preanthesis and wetter postanthesis than the normal periods. ‘Toronit’ almost always had the highest biomass yield (BY) and grain yield (GY). Except in 1999 under N0, ‘L94491? showed the highest % grain N concentration (GNC). Genotypes affected SPAD at almost all stages and N fertilization delayed leaf senescence for all genotypes and growth seasons. Correlations between SPAD at different growth stages and GY, N biomass yield at maturity (NBYM) and GNC were significant (P≤ 0.001), positive and strong/very strong (>r = 0.7). N translocation efficiency (NTE) was inversely related to PANU (~r = ? 0.77, P≤ 0.001), suggesting that N after anthesis is being preferentially transported to the ears to meet the N demand of the growing grains. It is concluded that there is still a large potential for increased NUE by improved N recirculation, use of fast and inexpensive crop N monitoring tools and high yielding, N uptake efficient genotypes.Abbreviations: NUE, Nitrogen use efficiency; SPAD, Minolta SPAD-502 chlorophyll meter, NHI, nitrogen harvest index; HI, Harvest index; NTE, N translocation efficiency from vegetative plant parts to grain; DMTE, dry matter translocation efficiency; CPAY, contribution of pre-anthesis assimilates to yield; PANU, Post-anthesis N uptake, d.a.s., days after sowing, N0, zero (0) kg ha?1 applied N fertilizer, N1, 250 kg ha?1 applied N fertilizer. 相似文献
11.
Francesco Montemurro Grazia Convertini Donato Ferri 《Journal of plant nutrition》2013,36(10):1681-1703
ABSTRACT Nitrogen (N) is one of the most growth restricting nutrients in cereal grain and represents one of the highest input costs in agricultural systems; therefore, environmental and economic considerations require the effective use of N fertilizer in plant production. This study was conducted for three years to better understand wheat plant response to optimize N fertilizer and how to reduce the risk of ground water pollution. Two of the most important durum wheat cultivars in Southern Italy and four N fertilization levels (0, 60, 120, and 180 kg N ha? 1, indicated as N0, N60, N120, and N180, respectively) were compared in this experiment. During plant growth, fresh and dry matter, plant nutritional state (SPAD readings and stem nitrate content), and N uptake were determined. At harvest, plant N content, N uptake, grain yield, yield components and quality were determined, allowing the calculation of the pre- and postanthesis N uptake and the N utilization efficiency indices. Furthermore, at the beginning and at the end of each year, soil mineral N was measured to calculate mineral N deficit in the soil. The results indicated that the treatment with 120 kg N ha? 1 of fertilizer ensures a good balance between yield and N utilization. In fact, N180 and N120 showed similar yield (3.01 and 3.07 t ha? 1, respectively) and protein content (13.7 and 13.5 %). Meanwhile, throughout the three-year experiment, N180 presented the highest final mineral N content in the soil at the end of the cropping cycles, increasing the amount of N available for leaching. The N120 treatment showed the same values of N utilization indices as compared to N180, indicating that further doses of N fertilizer did not increase wheat N utilization. Plant N status shows that it is possible to modify the N fertilization to reach its optimum level during plant growth, in accordance with variable weather conditions, and consequently the plants requirements. The mean treatments of the preanthesis N uptake were about 67.5% of the total N uptake, and it was significantly and positively correlated with wheat yield. On the contrary, the postanthesis N uptake showed positive correlation with grain protein content, confirming the importance of late N supply in grains quality. The variation of weather conditions affected winter wheat yield, quality, N utilization and plant N status, but any difference throughout years was found between N180 and N120, confirming that higher N rate did not influence wheat growth, yield, and N uptake. 相似文献
12.
Emílio Magaia Johan Arvidsson Rui Brito Abraham Joel 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2016,66(3):247-258
Average yield of maize (Zea mays L.) in Mozambique is low, mainly due to low use of inputs in agriculture, high seasonal rainfall variability and inadequate soil preparation. A study conducted in two summer crop seasons (November–March 2012/2013 and 2013/2014) examined the impact of three tillage methods (hand hoeing, strip tillage and conventional tillage), two fertiliser levels (0 and 40% N) and two water supply regimes (rainfed and irrigated) on maize root development and grain yield on a sandy soil in a semi-arid region of Mozambique. Tillage had a major effect on soil penetration resistance, but little effect on root growth and limited effect on yield. Thus, there appears to be little need for loosening on this soil. There was also no interaction between tillage and the other experimental factors, meaning that tillage system can be chosen irrespective of fertiliser and water supply. Irrigation had the largest impact on root and shoot growth and crop yield, increasing yield in season 2 from 670 to 4780?kg ha–1.There was a very strong interaction between fertiliser and water supply, with no yield increase for fertiliser in the rainfed treatment, while combined with irrigation it increased yield by 1590?kg ha–1 in season 1 and 1840?kg ha–1 in season 2. Thus, for the conditions studied here, it was rational to add fertiliser only in combination with irrigation and not in a rainfed system. 相似文献
13.
秸秆覆盖与氮肥运筹对杂交稻根系生长及氮素利用的影响 总被引:18,自引:2,他引:18
【目的】在我国稻-麦、稻-油等多熟制区域,富含氮素的小麦、油菜等水稻前茬作物秸秆被大量弃置、焚烧,造成极大浪费和环境污染,与此同时,稻季氮肥投入量却在逐年增加,因此在水稻生产中研究秸秆覆盖与氮肥配合施用的理论与技术,对实现秸秆还田与减少氮肥用量具有重要意义。本试验研究油菜、小麦2种秸秆覆盖方式下,3种不同的氮肥运筹方式对杂交稻主要生育时期根系生长、氮素吸收利用特征及产量的影响,并探讨其根系生长与氮素利用及产量间的关系,以期寻求最佳的秸秆还田与氮肥运筹搭配模式。【方法】本试验以杂交稻F优498为材料,采用两因素裂区试验设计,主区为小麦秸秆覆盖(S1)、油菜秸秆覆盖(S2)和无秸秆覆盖(S0);副区为氮肥运筹模式,在135 kg/hm2总施氮量条件下,设置基肥∶蘖肥∶穗肥为5∶3∶2(N1);基肥∶蘖肥∶穗肥为3∶3∶4(N2);基肥∶蘖肥∶穗肥为3∶1∶6(N3)3种氮肥运筹模式,以不施氮肥(N0)为对照。研究各处理杂交稻在移栽后20 d、移栽后30 d、齐穗期和成熟期根系生长及形态、各生育期的干物质与氮素积累,水稻茎鞘的干物质转运、产量及其构成因子以及各时期氮素积累及利用效率,同时对各生育时期根系生长与氮素利用及产量间的关系进行分析。【结果】结果表明,小麦秸秆覆盖均可有效促进杂交稻各生育时期的根系生长、改善根系形态、增加各时期的干物质与氮素积累,提高氮肥的利用效率及稻米产量。在不同种类秸秆覆盖下,基肥∶蘖肥∶穗肥(倒4叶龄期施入)为3∶3∶4(N2)时,可及时地对杂交水稻主要生育时期的根系生长进行调控,有效促进抽穗至成熟期的干物质积累与转运率,提高水稻主要生育时期的氮素积累及氮肥利用效率,显著增加稻谷产量,为本试验中最优的氮肥管理模式;而氮肥后移比例过高(基肥∶分蘖肥∶穗肥运筹比例为3∶1∶6),会限制齐穗期根系的生长,导致稻谷产量及氮肥利用效率降低。相关性分析表明,秸秆覆盖与氮肥运筹下主要生育时期根干重、根体积、总根长与产量及氮素吸收利用均存在显著或极显著的正相关(r=0.38*0.78**),尤其以齐穗期的根体积与总根长、根干重与氮素累积、产量及氮素回收利用率的相关性最好。【结论】小麦秸秆、油菜秸秆覆盖能够有效促进杂交稻根系的生长,增加干物质与氮素积累,提高氮肥利用效率,且小麦秸秆覆盖效果更显著。秸秆覆盖条件下,氮肥运筹以基肥∶蘖肥∶穗肥为3∶3∶4时的水稻根系生长旺盛,物质生产能力强,氮肥利用效率最高。因此,小麦秸秆覆盖与基肥∶蘖肥∶穗肥以3∶3∶4的比例配合的水稻的产量最高,为最优组合。 相似文献
14.
Julie Therese Christensen Musibau Oyeleke Azeez Rodrigo Labouriau Sabine Ravnskov Hanne Lakkenborg Kristensen Lars Juhl Munkholm Gitte Holton Rubæk 《Soil Use and Management》2022,38(1):991-1003
Lime and phosphorus (P) applications are common agricultural management practices. Our aim was to quantify the effects of long-term application practices on root growth and abundance of arbuscular mycorrhizal fungi (AMF) under field conditions. We assessed the effects of lime and P fertilizer applications on barley yield, root growth and AMF abundance in 2016. Treatments were no, low, medium and high liming rate corresponding to application of 0, 4, 8 and 12 Mg lime ha−1 every 5–9 years since 1942 combined with no or yearly application of 15.6 kg P ha−1 since 1944. At harvest, grain yield, root intensity (core-break) and AMF abundance at different soil depths were estimated. Root development was monitored during early growth with minirhizotrons in treatments receiving low, medium and high liming rates and P fertilization. A quadratic model relating grain yield to liming rate estimated yields to peak at 6.4 Mg lime ha−1 with yields of 4.2 and 3.2 Mg grain ha−1 with and without P fertilization, respectively. Low and medium liming rates resulted in greater AMF abundance, especially in the no P treatments. During early growth in P-fertilized treatments, 77% and 65% more roots developed in the soil profile when treated with medium and high liming rate, respectively, compared to low liming rate. We conclude that long-term application of lime in soils receiving yearly P fertilization improved conditions for root growth in soil layers below 30 cm, but at the high liming rate, this did not translate into higher yield. 相似文献
15.
中国玉米小麦产量与氮肥利用效率同步提高的研究进展 总被引:20,自引:0,他引:20
Achieving both high yield and high nitrogen use efficiency (NUE) simultaneously has become a major challenge with increased global demand for food, depletion of natural resources, and deterioration of environment. As the greatest consumers of N fertilizer in the world, Chinese farmers have overused N and there has been poor synchrony between crop N demand and N supply because of limited understanding of the N uptake-yield relationship. To address this problem, this study evaluated the total and dynamic N requirement for different yield ranges of two major crops (maize and wheat), and suggested improvements to N management strategies. Whole-plant N aboveground uptake requirement per grain yield (N req) initially deceased with grain yield improvement and then stagnated, and yet most farmers still believed that more fertilizer and higher grain yield were synonymous. When maize yield increased from < 7.5 to > 12.0 Mg ha-1, Nreq decreased from 19.8 to 17.0 kg Mg-1 grain. For wheat, it decreased from 27.1 kg Mg-1 grain for grain yield < 4.5 Mg ha-1 to 22.7 kg Mg-1 grain for yield > 9.0 Mg ha-1. Meanwhile, the percentage of dry matter and N accumulation in the middle-late growing season increased significantly with grain yield, which indicated that N fertilization should be concentrated in the middle-late stage to match crop demand while farmers often applied the majority of N fertilizer either before sowing or during early growth stages. We accordingly developed an integrated soil-crop system management strategy that simultaneously increases both grain yield and NUE. 相似文献
16.
Zhongwei Tian Xiaoxue Liu Jinhong Yu Shilu Gu Lei Zhang Dong Jiang 《Archives of Agronomy and Soil Science》2020,66(10):1384-1398
ABSTRACT A two-year field and micro-plot 15N-labelled experiment was conducted under two levels of N application rate (240 and 180 kg N ha–1) with three basal N application stages [seeding (L0), four-leaf stage (L4), and six-leaf stage (L6)] to investigate the effects of reducing basal N application amount and postponing basal N fertilization period on wheat growth and N use efficiency (NUE). No significant differences were observed in grain yield, root growth and root morphology between the N180L4 and N240L0 treatments, while the root-shoot ratio of N180L4 was significantly improved. Postponing basal N application period increased the residual basal 15N in soil and reduced basal 15N loss, and N180L4 treatment favored the highest 15N recovery efficiency (NRE), mainly due to reduced 15N loss. Grain yield and basal NRE were significantly positively correlated with root dry weight in deeper soil layers (40–60 cm), and the contribution of root growth to improved grain yield and NRE increased with the downward distribution of the roots. Therefore, postponing the basal N fertilization period under N deficiency promotes deeper root growth during the post-jointing period and increases basal N uptake, as well as reducing basal N loss and increasing grain yield and NUE. 相似文献
17.
Muhammad S. A. KHAN Lynette K. ABBOTT Zakaria M. SOLAIMAN Peter R. MAWSON Ian S. WAITE Sasha N. JENKINS 《土壤圈》2022,32(2):339-347
Excess nitrogen(N) fertiliser use in agriculture is associated with water pollution and greenhouse gas emissions.While practices and programs to reduce N fertiliser application continue to be developed,inefficient fertiliser use persists.Practices that reduce mineral N fertiliser application are needed in a sustainable agricultural ecosystem to control leaching and gaseous losses for environmental management.This study evaluated whether fully or partially replacing mineral N fertiliser with zoo compost(Perth Zoo) could be a good mitigation strategy to reduce mineral N fertiliser application without affecting wheat yield and nutrition.To achieve this,a glasshouse experiment was conducted to assess the complementary effect of zoo compost and mineral N fertiliser on wheat yield and nutrition in a sandy soil of southwestern Australia.Additionally,a chlorophyll meter was used to determine whether there was a correlation between chlorophyll content and soil mineral N content,grain N uptake,and grain protein content at the tillering(42 d after sowing(DAS)) and heading(63 DAS) growth stages.The standard practice for N application for this soil type in this area,100 kg ha-1,was used with a soil bulk density of 1.3 g cm-3 to calculate the amount of mineral N(urea,46% N) and Perth Zoo compost(ZC)(0.69% N) for each treatment.Treatments comprised a control(no nutrients added,T1),mineral N only(100 kg N ha-1,T2),ZC only(100 kg N ha-1,T7),and combinations of mineral N and ZC at different rates(mineral N at 100 kg N ha-1+ ZC at 25 kg N ha-1(T3),mineral N at 75 kg N ha-1+ ZC at 25 kg N ha-1(T4),mineral N at 75 kg N ha-1+ ZC at 50 kg N ha-1(T5),and mineral N at 50 kg N ha-1+ ZC at 50 kg N ha-1(T6)).The T6 treatment significantly increased grain yield(by 26%) relative to the T2 treatment.However,the T7 treatment did not affect grain yield when compared to the T2 treatment.All treatments with mineral N and ZC in combination significantly improved the 1 000-grain weight compared to the T2 treatment.Chlorophyll content was better correlated with soil mineral N content(r = 0.61),grain N uptake(r = 0.62),and grain protein content(r = 0.80) at heading(63 DAS) than at tillering(42 DAS).While ZC alone could not serve as an alternative to mineral N fertiliser,its complementary use could reduce the mineral N fertiliser requirement by up to 50% for wheat without compromising grain yield,which needs to be verified in the field.Chlorophyll content could be used to predict soil mineral N at the heading stage,and further studies are warranted to verify its accuracy in the field.Overall,the application of ZC as part of integrated nutrient management improved crop yield with reduced N fertiliser application. 相似文献
18.
Nitrate‐N uptake from soil depends on root growth and uptake activity. However, under field conditions N‐uptake activity is difficult to estimate from soil‐N depletion due to different loss pathways. We modified the current mesh‐bag method to estimate nitrate‐N‐uptake activity and root growth of two oilseed‐rape cultivars differing in N‐uptake efficiency. N‐efficient cultivar (cv.) ‘Apex' and N‐inefficient cv. ‘Capitol' were grown in a field experiment on a silty clayey gleyic fluvisol near Göttingen, northern Germany, and fertilized with 0 (N0) and 227 (N227) kg N ha–1. In February 2002, PVC tubes with a diameter of 50 mm were installed between plant rows at 0–0.3 and 0–0.6 m soil depth with an angle of 45°. At the beginning of shooting, beginning of flowering, and at seed filling, the PVC tubes were substituted by PVC tubes (compartments) of the same diameter, but with an open window at the upper side either at a soil depth of 0–0.3 or 0.3–0.6 m allowing roots to grow into the tubes. Anion‐exchange resin at the bottom of the compartment allowed estimation of nitrate leaching. The compartments were then filled with root‐free soil which was amended with or without 90 mg N (kg soil)–1. The newly developed roots and nitrate‐N depletion were estimated in the compartments after the installing period (21 d at shooting stage and 16 d both at flowering and grain‐filling stages). Nitrate‐N depletion was estimated from the difference between NO ‐N contents of compartments containing roots and control compartments (windows closed with a membrane) containing no roots. The amount of nitrate leached from the compartments was quantified from the resin and has been taken into consideration in the calculation of the N depletion. The amount of N depleted from the compartments significantly correlated with root‐length density. Suboptimal N application to the crop reduced total biomass and seed‐yield formation substantially (24% and 38% for ‘Apex’ and ‘Capitol’, respectively). At the shooting stage, there were no differences in root production and N depletion from the compartments by the two cultivars between N0 and N227. But at flowering and seed‐filling stages, higher root production and accordingly higher N depletion was observed at N0 compared to N227. Towards later growth stages, the newly developed roots were characterized by a reduction of root diameter and a shift towards the deeper soil layer (0.3–0.6m). At low but not at high N supply, the N‐efficient cv. ‘Apex’ exhibited higher root growth and accordingly depleted nitrate‐N more effectively than the N‐inefficient cv. ‘Capitol’, especially during the reproductive growth phase. The calculated nitrate‐N‐uptake rate per unit root length was maximal at flowering (for the low N supply) but showed no difference between the two cultivars. This indicated that the higher N‐uptake efficiency of cv. ‘Apex’ was due to higher root growth rather than higher uptake per unit of root length. 相似文献
19.
Pilar Muschietti-Piana Therese M. McBeath Ann M. McNeill Pablo A. Cipriotti Vadakattu V. S. R. Gupta 《植物养料与土壤学杂志》2020,183(3):355-366
Soil nitrogen (N) supply for wheat N uptake can be manipulated through legume and fertilizer N inputs to achieve yield potential in low‐rainfall sandy soil environments. Field experiments over 2 years (2015–2016) were conducted at 2 different sites in a low‐rainfall sandy soil to determine the soil N supply capacity relative to wheat N uptake at key growth stages, after a combination of crop residue (removed, wheat or lupin) and fertilizer N (nil, low or high N) treatments were manipulated to improve wheat yield. We measured the temporal patterns of the soil profile mineral N and PAW to 100 cm depth, wheat aerial biomass and N uptake in both years. In 2016 we also measured the disease incidence as a key environmental variable. There was 35 kg ha?1 more soil mineral N to 100 cm depth following lupin than wheat residues at the end of the fallow on average in both years. In a below average rainfall season, wheat biomass produced on lupin residues was responsive to N input with soil profile mineral N depleted by increased crop N uptake early in the season. In an above average rainfall season, a higher soil mineral N supply increased actual and potential grain yield, total biomass, N uptake, harvest index and water use efficiency of wheat, regardless of the source of N. Our study showed that the combination of lupin residues with high N rate increased soil profile mineral N at early growth stages, providing a greater soil N supply at the time of high wheat N demand, and the inclusion of a legume in the rotation is critical for improving the N supply to wheat, with added disease break benefits in a low‐rainfall sandy soil environment. 相似文献
20.
M. Yusuf Ali Selim Ahmed Chris Johansen David Harris J. V. D. K. Kumar Rao 《植物养料与土壤学杂志》2007,170(2):296-302
Root traits of six different crops grown on residual soil moisture in the post–rainy season in the High Barind Tract (HBT) of Bangladesh were investigated to better understand their adaptation to this moisture‐limited environment. Deep‐rooting chickpea is the currently favored rainfed crop grown after rainy‐season rice in the HBT, but it is necessary to identify alternative crops to chickpea in order to avoid buildup of pests and diseases. Averaged over 2 y, barley (1.72 Mg ha–1) produced significantly more grain than chickpea (1.4 Mg ha–1) which, in turn, yielded better than linseed (1.0 Mg ha–1), wheat (0.93 Mg ha–1), and mustard (0.77 Mg ha–1). Lentil did not produce any grain at all. Grain yield for all crops increased as total root length increased above a threshold value of 0.05 to 0.1 km m–2. In general, grain yield increased as the proportion of total root produced below 60 cm depth increased, although barley also had thin roots that could more effectively extract soil moisture. Expression of root traits varied considerably between seasons, which was attributable to the different rainfall patterns and bulk‐density characteristics of the soil profile in the 2 years of the study. Although favorable root traits, particularly rooting ability below 60 cm, are a prerequisite for acceptable yield levels of crops grown on residual soil moisture in the HBT, it is recognized that farmers' choice of a post‐rice crop will depend on its economic return or food‐security value. 相似文献