Fertilizer ^(15)N Accumulation, Recovery and Distribution in Cotton Plant as Affected by N Rate and Split

N fertilization of 300 kg N ha-1 is normally applied to cotton crops in three splits： pre-plant application （PPA, 30%）, first bloom application （FBA, 40%） and peak bloom application （PBA, 30%） in the Yangtze River Valley China. However, low fertilizer N plant recovery （NPR） （30-35%） causes problems such as cotton yield stagnation even in higher N rate, low profit margin of cotton production and fertilizer release to the environment. Therefore, it is questioned： Are these three splits the same significance to cotton N uptake and distribution？ An outdoor pot trial was conducted with five N rates and 15 N labeled urea to determine the recovery and distribution of 15N from different splits in cotton （Gossypium hirsutum L. cv. Huazamian H318） plant. The results showed that, cotton plant absorbed fertilizer 15N during the whole growing period, the majority during flowering for 18-20 d regardless of N rates （150-600 kg ha-1）. Fertilizer 15N proportion to the total N accumulated in cotton plant increased with N rates, and it was the highest in reproductive organs （88% averaged across N rates） among all the plant parts. FBA had the highest NPR （70%）, the lowest fertilizer N lose （FNL, 19%）, and the highest contribution to the fertilizer 15N proportion to the total N （46%） in cotton plant, whereas PPA had the reverse effect. It suggests that FBA should be the most important split for N absorption and yield formation comparatively and allocating more fertilizer N for late application from PPA should improve the benefit from fertilizer.

Effect of Long-Term Application of K Fertilizer and Wheat Straw to Soil on Crop Yield and Soil K Under Different Planting Systems

Effect of application of K fertilizer and wheat straw to soil on crop yield and status of soil K in the plough layer under different planting systems was studied. The experiments on long-term application of K fertilizer and wheat straw to soil in Hebei fluvo aquic soil and Shanxi brown soil in northern China were begun in 1992. The results showed that K fertilizer and straw could improve the yields of wheat and maize with the order of NPK ＋ St 〉 NPK 〉 NP ＋ St 〉 NP, and treatment of K fertilizer made a significant difference to NP, and the efficiency of K fertilizer in maize was higher than in wheat under rotation system of Hebei. In contrast with Shanxi, the wastage of soil potassium was a more serious issue in the rotation system in Hebei, only treatment of NPK ＋ St showed a surplus of potassium and the others showed a wane. K fertilizer and straw could improve the content of water-soluble K, nonspecifically adsorbed K, non-exchangeable K, mineral K, and total K in contrast to NP; however, K fertilizer and straw reduce the proportion of mineral K and improve proportion of other forms of potassium in the two locating sites. Compared with the beginning of orientation, temporal variability character of soil K content and proportion showed a difference between the two soil types; furthermore, there was a decrease in the content of mineral K and total K simultaneously in the two locating sites. As a whole, the effect of K fertilizer applied to soil directly excelled to wheat straw to soil. Wheat straw to soil was an effective measure to complement potassium to increase crop yield and retard the decrease of soil K.

Effects of Long-Term Application of Inorganic Fertilizers on Biochemical Properties of a Rice-Planting Red Soil

一个长期的实验在江西省的 Yingtan 被建立在从第四级的红壤导出的种大米的土壤的生物化学的性质上调查无机肥料的长期的申请的效果。Noncultivated 土壤被低 pH 和缺乏极其在可得到的营养素，特别地 P 和 N 侵蚀并且描绘。在 13 年在为双 cropped 大米的耕作的无机的授精以后，土壤的生物化学的性质被改变。没有 N 申请，氮的硝化作用潜力和脲酶活动比那些在有 N 申请的处理是更高的。没有 P 申请，酸性磷酸酶活动和脱氢酶活动比在那些在有 P 申请的处理也是更高的。脱氢酶活动与全部的 P 和 hydrolysable N 的集中并且与米饭庄稼产量相关很好，建议那项脱氢酶活动可能是为在土壤肥力的改进的合适的指示物。

Distribution of Crystal Organic Fertilizer-N in Soil-plant System

The distribution of crystal organic fertilizer, urea and compound fertilizer-N in soil and plant system was researched with 15N-trace under tobacco pot experiment. The results showed that the leaf yield of tobacco used crystal organic fertilizer was 23.1% and 14.6% higher than that of urea and compound fertilizer treatments respectively. Compound fertilizer also resulted in higher yield of 8.5 % comparing with the urea treatment. Nitrogen content of the plant from the crystal organic fertilizer treatment was 138. 6% and 145.7% as high as that of the compound fertilizer and urea treatments respectively. The absorbed N from the organic fertilizer was 25.1% and 27.9% more than that from the compound fertilizer and urea respectively. However, the absorbed N from the soil with the organic fertilizer was 47.4% and 58.3% more than that with compound fertilizer and urea respectively. The N use efficiency of the organic fertilizer was 9.4% and 10.1% higher than that of the compound fertilizer and urea. It indicated that the crystal organic fertilizer not only had high N use efficiency, but also stimulated tobacco taking up more N from soil.

THE INFLUENCE OF FERTILIZERS, NaHCO_3,SOIL TYPE ON CHEMISTRY OF FLOODED SOILS AND RICE PLANT GROWTH

This research was conducted to study the influence of NaHCO3and fertilizer treatments on flooded soils tothe chemistry of soil and rice plant growth.The experiment was done in a greenhouse using a split-split plot design ofthree factors: two types of soil,three doses of fertilizers and three levels of NaHCO3with three replications.The firstfactor was two kind of soils Fluvaquent and Calciquert,the factor was without nutrient(blank),macro nutrients,andcompletely nutrients(second macro and micro nutrients),and the third factor was 0 mg/kg,200 mg/kg and 400 mg/kgof NaHCO3or equivalent with 0 mg,1 200 mg and 2 400 mg NaHCO3per pot.Each experimental unit used a pot of 10L capacity and filled with soil mud equivalent with 6 kg of dried soil.After each of treatment combination mixed into themud soil,two plants of IR-32 variety were grown,and flooded at5 cm high accordingly with growth period.Parametersobserved were the growth of tillers,electrical conductivity(E.C.) and pH.The experiment results showed that the treatment of NaHCO3increased the soluble salt content(E.C.) and soilacidity(pH) during flooding on Calciquerts and Fluvaquents.The content of soluble salt decreased to 2.0 mmhos/cm,while pHon Calciquert decreased towards the neutral pH.Anyhowthe pHon Fluvaquents increased approach to neutral.The treatments of NaHCO3inhibited the tiller growth,either macro fertilizer and completely fertilizer increased thetillers,but did not improve the negative effect of alkalinity due to of NaHCOtreatment.

Effects of Plant-derived Humic Acid Organic Fertilizer on Selenium Content of Rice in Northern Guangxi

This study was to find out the suitable application amount of plant-derived humic acid organic fertilizer for selenium-rich rice production in northern Guilin area by applying the fertilizer at different amounts.The results showed that plant-derived humic acid organic fertilizer could effectively activate selenium in selenium-rich soil,and then promote the uptake of selenium by rice.With costs,selenium enrichment and rice yield as the main evaluation indicators,A4 was chosen as the best treatment,that is,the application of 4 500 kg/hm^2 of plant-derived humic acid organic fertilizer as base fertilizer could achieve the best benefit.

A Study of Heavy Metals in the Dust Fall around Assiut Fertilizer Plant

A study of an environmental assessment of dust fall and the associated heavy metal contents was conducted during the period from the first of March 2011 to the end of February 2012 at adjoining area of a phosphate fertilizer plant. Around the industrial area 8 dust fall stations were established and one of them was built upwind far from pollution activities to be taken as a control sample. Dust fall samples collected monthly weighed and then prepared to be analyzed through Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS) to obtain heavy metal concentration. Meteorological parameters influencing the distribution of dust fall such as wind speed and direction, temperature, humidity, rain fall and pressure were determined. Results showed that deposition flow rates were 38.2. 47.5, 57.7, 44.3, 39.4, 38.2, 42.7 and 5.9 g/m2·month for the sites No., 1, 2, 3, 4, 5, 6, 7 and 8 respectively, and were compared with the findings of other investigators of like industrial areas worldwide. Levels of heavy metal As, Cu, Pb, Zn, Cd, and Hg in the deposited dust fall were 3.30, 26.46, 22.33, 235.00, 4.53 and 3.80 μg/g respectively. Enrichment coefficients of the heavy metals in the dust fall were found to be significant and reached the values 1.81, 0.90, 0.85, 0.65, 0.41 and 0.35 for zinc, lead, cadmium, copper, mercury and arsenic respectively. The paper ends with results and recommendations suggesting a methodology to remediate the investigated area polluted with heavy metals and control measures for the fertilizer plant to reduce pollution into the surrounding environment.

The bio-interactions between plants,insecticides and fertilizers:an innovative approach for the research of xenobiotic substances

In this experiment carried out on Caribbean chili pepper plants(Capsicum chinensis),the bio-insecticide azadirachtin in combination with an NPK fertilizer proved to have a greater lethal impact on the larvae of Aedes albopictus than each substance on its own.This synergistic effect is noticeably important when both inputs are sprayed directly on the leaves of the plant(foliar application).While the plants treated with azadirachtin or NPK alone cause a 33.6%and 36.4%mortal-ity respectively of the Ae.albopictus larvae,the combination of the two inputs induces a 74.4%mortality on the mosquito larvae.To account for this synergistic effect phenomenon inside the plant,the azadirachtin+NPK combination most likely interacts with the capsaicinoid compounds naturally produced by the plant.Not only does this study carried out on azadirachtin reveal major results but the methodology itself offers a most interesting approach on how to boost the agricultural inputs within the plants.As a matter of fact,this research axis demands developing since the control of pests harmful to men has been dramatically lacking insecticide molecules acting on new targets over the past three decades.

Effects of Sinochem Microbial Organic Fertilizer on Tea Plants

[Objectives]This study was conducted to explore the application effects of Sinochem microbial organic fertilizer on tea plants.[Methods]Through the experiment and demonstration of Sinochem microbial organic fertilizer,its effects on the yield and quality of tea and the physical and chemical quality of soil were explored.[Results]Compared with the conventional organic fertilizer cake fertilizer,the fertilizer could increase the weight of freshly picked bud leaves,increase the yield of tea,and thus promote the growth of tea plants.It increased the contents of chlorophyll components,amino acids and tea polyphenols,the main functional substances of tea,which was conducive to improving the internal quality of tea.It improved the physical and chemical properties of soil,and increased the contents of organic matter,alkali-hydrolyzable nitrogen and available phosphorus in tea garden soil.It also had a good effect in improving soil environmental health indexes and physical and chemical properties,and did not contain heavy metals and plant growth hormones.[Conclusions]This study provides a theoretical basis for the popularization and application of Sinochem microbial organic fertilizer.

Gas Exchange and Growth of Medicinal Plant Subjected to Salinity and Application of Biofertilizers

The objective of this study was to evaluate the use of biofertilizers and saline waters on gas exchange and growth of medicinal plant Plectrantus amboinicus. The experiment was conducted in the period February to May 2013 in a greenhouse. The experimental design was completely randomized in a 2 × 4 factorial arrangement, with two levels of salinity of irrigation water (ECw: 0.7 and 3.1 dS m-1) and four levels of bovine liquid biofertilizer applied to the soil, corresponding to 0%, 10%, 20% and 30% of the soil volume, with five replications. The experiment lasted 60 days, counted from the beginning of the treatments. The stomatal conductance (gs), photosynthesis (A), transpiration (E), intrinsic water use efficiency (WUEi) were performed at the end of the experiment, and the height, number of leaves and stem diameter at the beginning and at the end. Generally plants subjected to salinity of irrigation water of 3.1 dS m-1 had the lowest values of gas exchange. Moreover, the application of biofertilizers and the interaction between this and salinity did not affect any growth variable studied except the stem length in the final phase which was influenced by salinity at 5% probability by F test. The average values of this variable were 57.22 cm and 69.65 cm when applied water ECw: 0.7 to 3.1 dS m-1, respectively. The application of biofertilizers can reduce the effect of salinity on the final plant height of Plectrantus amboinicus, especially when the plants were fertilized with a dose of 20% of biofertilizers.

Effects of Different Application Rates of Bioorganic Fertilizer on the Growth of Spinach in a Short Term

[Objectives]This study was conducted to promote the rational use of bioorganic fertilizers.[Methods]Stanley bioorganic fertilizer was selected to investigate the laws and characteristics of the effects of bioorganic fertilizer on spinach growth with different application rates in a short term and found out the precise application rate.[Results]As the application rate of bioorganic fertilizer increasing,the emergence rate of spinach decreased.The total weights and leaf areas of spinach plants treated with different application rates of bioorganic fertilizers were all higher than those of the control check(CK).The total weights and leaf areas of spinach plants applied with bioorganic fertilizer at different rates were all higher than those of the CK.The total weight of spinach plants increased linearly with the application rate of bioorganic fertilizer increasing among treatments,while the leaf area fluctuated with the increase of bioorganic fertilizer concentration among various treatments.The average root volumes and average diameters of treatments applied with bioorganic fertilizer at different rates were all higher than those in the CK,but the average root length showed a different trend.The average root length was higher in the CK than in various bioorganic fertilizer treatments in the early growth period,but the differences of various treatments from the CK gradually decreased in the middle period,and in the later period,the root length of spinach treated with organic fertilizer gradually exceeded the CK.[Conclusions]This study provides a theoretical basis for the rational application of bioorganic fertilizers in spinach production.

施肥量与种植密度对田润189玉米主要农艺性状及产量的影响

以自主选育玉米新品种田润189为试验材料,采用二因素裂区试验设计,主区为种植密度,设3个密度水平处理(A1处理42000株/hm^(2);A2处理48000株/hm^(2);A3处理54000株/hm^(2)),副区为施肥量,设4个施肥水平处理(B1处理为常规施肥,施用复合肥750 kg/hm^(2)和尿素150 kg/hm^(2);B2、B3和B4处理分别施用缓释肥600、750和900 kg/hm^(2)),探究田润189在3个密度4个施肥量水平条件下玉米主要农艺性状、产量及经济效益的表现。结果表明,种植密度、施肥量及肥密互作对植株性状、果穗性状及产量均存在显著或极显著影响。在不同种植密度条件下,田润189的产量以A3处理最高,且显著或极显著高于A1处理,但与A2处理差异不显著;在不同施肥量条件下,田润189的产量以B4处理最高,且极显著高于B2处理,但与B3和B1处理差异不显著;在肥密互作中,春播以A3B1处理的产量最高,达8494.50 kg/hm^(2)且显著高于A3B2处理,但与A3B4和A3B3处理差异不显著,而秋播以A3B4处理的产量最高(8276.50 kg/hm^(2)),显著高于A3B2处理,但与A3B1和A3B3处理差异不显著。从经济效益上看,施用缓释肥处理(B2、B3和B4处理)的收益均比常规施肥处理(B1处理)高,尤其B3处理的收益最高,达12353.59元/hm^(2),比B1处理平均增收10.77%。综上所述,田润189玉米的较佳种植密度为48000~54000株/hm^(2),在此密度下施用750~900 kg/hm^(2)缓释型复合肥(N-P 2O 5-K 2O=24-6-10)可获得较佳的产量和经济效益。

新型旋耕开沟施肥播种机的设计与研究

针对播种施肥难的问题,结合垄作区作物种植的农艺要求,设计了一款新型旋耕开沟施肥播种机。机具适用于小麦、大豆和玉米垄上栽培技术,可实现精确深施肥、精密播种、开沟、覆土和镇压等作业,为小麦、大豆和玉米的规模化、机械化作业提供了一定的技术支撑。试验结果表明:设计的新型旋耕开沟施肥播种机对降低漏播、提高播种深度和植株距离的合格率具有重要意义,大大提高了作业质量和效率。

基于插值法分析施肥量和留叶数对烤烟的影响

为明确烤烟适宜的施肥量和留叶数,提升烟叶生产过程中的综合效益,以施肥量和留叶数为变量,采用正交试验设计,通过插值的方法分析了不同施肥量、留叶数对烤烟农艺性状、经济性状、品质性状的影响。结果表明:随着施肥量由450 kg·hm^(-2)增加至600 kg·hm^(-2),烤烟长势显著提升,产量、均价、中部和上部烟叶主要化学成分协调性评价总分逐渐提高;随着留叶数由每株16片增加至20片,成熟期最大叶面积与倒3叶面积差值逐渐增大,株形呈“倒塔形”-“筒形”-“塔形”变化。产量、产值分别提高20.8%、18.8%,上等烟率、均价分别降低7.6%、1.5%,烟叶种植净收益逐渐提高,中部和上部烟叶主要化学成分协调性评价总分均呈现先升高后降低的变化趋势。在烟叶生产过程中,适度提高养分供给强度,并增加留叶数,有利于提高烟叶品质,且烟农种植净收益较高。

不同株型小花生品种氮素养分吸收利用特性

南方小花生植株高大的地方良种与矮化改良的品种并存。为探明其需氮规律,实现差异化施肥的高产管理,以湖南主栽的高秆地方良种安化小籽、矮秆现代品种湘黑小果为材料,设置4个基施复合肥用量0、450、600、750 kg/hm^(2),分别代表土壤背景(CK)、低肥(F30)、中肥(F40)、高肥(F50)水平,于4个生育时期测定并分析植株各器官氮含量、积累与分配状况。结果表明:氮含量以高秆品种果>叶>根>茎为序;矮秆品种则以叶>果>根>茎为序。叶、根氮含量表现为高秆<矮秆,而茎、果反之。增施肥料对氮含量的影响程度总体趋势为茎>叶>根>果,利于营养器官的氮素同化吸收。氮积累量两品种各器官以叶>果>茎>根为序。除苗期外,其余时期的全株、叶、茎氮积累量表现为高秆>矮秆;根在苗期、结荚期为高秆<矮秆,其余时期相反;果则为高秆<矮秆。施肥利于营养器官前期的氮素积累。氮素分配率两品种均以叶最高,荚果和茎其次,根最少。地上部为高秆>矮秆,而地下部反之,说明矮秆植株吸收的氮素更利于转运到荚果。氮素利用效率均为矮秆>高秆,氮素生产效率、氮肥偏生产力两品种均以F40、F30最高,过度施肥降低氮素利用效率。综上,矮秆品种氮素积累量对增肥的响应度较低,总积累量虽然较少而在荚果中分配较多,并具有更高的氮素利用效率;品种株型特点应作为南方典型贫瘠酸性红壤区小籽花生生产上确定施肥量的主要依据。

不同干扰方式形成的内蒙古大兴安岭白桦次生林的土壤肥力

在内蒙古大兴安岭北部林区(根河林业局的潮查林场、木瑞林场、上央格气林场),选择经火烧干扰(重度火烧、中度火烧)、渐伐干扰(重复样地2块)、渐伐干扰后进行补植(重复样地2块)、皆伐干扰、未干扰形成的白桦次生林,共设置8块样地;在每个样地内按对角线均匀设置3个土壤样方,采用环刀法在土层深度(h)0<h≤10 cm、10 cm<h≤20 cm土层采集土壤样品,在采集土壤样品的同时分类记录每个样地的乔木、灌木、草本种名和数量;以土壤含水量、pH、有机质质量分数、全氮质量分数、全磷质量分数、全钾质量分数、速效氮质量分数、速效磷质量分数、速效钾质量分数共计9个因素为评价指标,采用改进的内梅罗综合指数法综合评价土壤肥力、采用Margalef丰富度指数法分析群落物种丰富度、采用单因素方差分析法(One-way ANOVA)分析各土壤因素间显著性、采用皮尔逊(Pearson)相关性分析法分析土壤因素与植物多样性的相关性。结果表明:白桦次生林的土壤含水量、有机质质量分数、全磷质量分数、速效钾质量分数、全钾质量分数、速效磷质量分数均值较高,土壤全氮质量分数、速效氮质量分数均值较低。白桦次生林表层土壤(0<h≤10 cm)营养元素质量分数更高,且0<h≤10 cm、10 cm<h≤20 cm两层土层间土壤理化性质变化较小。各样地的草本、灌木丰富度较高,乔木偏低。白桦次生林土壤综合肥力系数范围1.22~1.63,整体都处于中等水平;经过皆伐、渐伐后补植、未干扰的林地土壤肥力更高些,而经过火烧、渐伐干扰的林地土壤肥力更低些。土壤有机质质量分数、全氮质量分数是白桦次生林土壤肥力的主要影响因子。土壤有机质质量分数与乔木丰富度呈显著正相关(P<0.05)、pH与草本丰富度呈显著正相关(P<0.05),土壤全磷质量分数与灌木丰富度呈显著负相关(P<0.05)、速效氮质量分数与草本丰富度呈显著负相关(P<0.05)。不同干扰方式形成的白桦次生林土壤营养元素质量分数偏高(除氮元素外),土壤肥力较好,植物丰富度较高;采伐、火烧干扰显著降低了土壤肥力,而通过合理的人为干扰可以恢复部分土壤肥力。

2种新型肥料对大豆肥密效应及土壤酶活的影响研究

为研究2种新型肥料及其配套施用方法对大豆肥密效应及土壤酶活的影响,本研究以‘中龙豆120’为试验材料,设置6个施肥处理(空白施肥、正常施肥、低浓度硫代硫酸铵、高浓度硫代硫酸铵、0.5肥+铜大师、0.3肥+铜大师,分别记作T_(1)、T_(2)、T_(3)、T_(4)、T_(5)、T_(6))为主区和3个种植密度水平(15×10^(4)、20×10^(4)、25×10^(4)株/hm^(2),分别记作M1、M2、M3)为副区进行裂区试验。结果表明:在同一施肥处理下,大豆产量随种植密度的增加先上升后下降,在M2处取得最大值;随着种植密度的增加,主茎粗、叶绿素含量逐渐减少,株高、叶面积指数逐渐增大。在同一种植密度下,硫代硫酸铵处理较T_(1)、T_(2)相比增加了产量、叶面积指数、土壤蔗糖酶和碱性磷酸酶活性,但是降低了大豆株高、主茎粗与土壤脲酶活性,T_(3)处理较T_(1)、T_(2)相比均增加了叶绿素含量,T_(4)较T_(1)相比增加了叶绿素含量;铜大师处理在M3密度下种植时相对T_(1)、T_(2)显著提高大豆产量但此时与其他种植密度相比整体产量较低,铜大师处理下大豆株高、主茎粗、叶面积指数及土壤酶活性趋势整体上均低于T_(1)、T_(2),叶绿素含量呈相反的结果。综上所述:20万株/hm^(2)时硫代硫酸铵处理是最优栽培模式,且在M_(2)T_(4)下达到产量最大值3200.00 kg/hm^(2),铜大师在大豆上的应用我们应做下一步探索。

种植密度与施肥水平对甜荞光合特性、产量及抗倒伏的影响

【目的】合理密植与施肥,可有效协调个体间的竞争,改善群体光环境,构建高产群体,是提高作物高产的重要途径。探讨不同种植密度和施肥水平对甜荞抗倒性能及产量的影响,为荞麦抗倒高产高效栽培提供技术参考。【方法】以等花柱甜荞新品种西农D4103为试验材料,黄土高原主栽品种西农9976为对照,采用双因素裂区设计,主因素为2个栽培密度,分别为D1:90万株/hm2、D2:135万株/hm2;副因素为低、中、高3个施肥水平,分别为F1(N:120、P2O5:76.8、K2O:56.4 kg·hm^(-2))、F2(N:180、P2O5:115.2、K2O:84.6 kg·hm^(-2))和F3(N:240、P2O5:153.6、K2O:112.8 kg·hm^(-2)),于2021—2022年在西北农林科技大学榆林小杂粮试验站进行。研究不同种植密度和施肥水平对甜荞群体冠层结构及光合特性、产量及产量构成因素、倒伏特性的变化规律。【结果】2年大田试验表明,提高种植密度,使甜荞群体叶面积指数(LAI)显著增加,光合有效辐射(PAR)和相对叶绿素含量(SPAD)显著下降,并减弱了叶片光合能力。施肥显著提高了甜荞群体LAI、SPAD和光合能力,降低了PAR,中肥水平较低肥水平的LAI、SPAD、净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(Tr),平均增加14.6%、6.7%、15.3%、15.2%和16.6%,PAR和胞间CO_(2)浓度(Ci)平均减少4.5%和6.7%。D2较D1处理的株高、重心高度、第2节间长、倒伏率和倒伏指数平均增加9.6%、12.5%、24.7%、19.8%和26.2%,而第2节间粗、充实度、抗折力和整株鲜重减少13.1%、7.4%、18.3%和8.5%。同等密度下增加施肥量,使甜荞株高、重心高度、第2节间长、整株鲜重、倒伏率和倒伏指数逐渐增加,第2节间粗、第2节间充实度、第2节间抗折力呈先增加后减小的趋势。提高种植密度和施肥水平,使甜荞产量显著增加,西农D4103的产量在D2F2处理下达最大值,较D1F1增产15.1%,较对照品种在同等施肥量下增产17.0%。【结论】构建合理的甜荞群体结构有利于增加群体受光面积,改善光合特性,降低田间倒伏率,从而提高产量。因此,黄土高原地区等花柱甜荞品种西农D4103推荐种植密度为135万株/hm2,肥料施用量为中等施肥水平(N:180 kg·hm^(-2)、P2O5:115.2 kg·hm^(-2)、K2O:84.6 kg·hm^(-2))。