钾氮配施对大蒜生长和养分吸收的影响

连续三年多点研究钾氮配施对大蒜生长及养分吸收利用的影响。结果表明:施用钾肥对大蒜的生长发育有明显的促进作用,三年试验平均,蒜苗、蒜苔和蒜头产量较不施钾的对照分别增长29.8~53.7%、30.4~39.7%和19.8~28.2%,平均增产42.9%、35.5%和24.1%。施用适量的氮钾肥提高了大蒜地上部茎叶含N量,大幅度增加茎叶、蒜苔、蒜头和全株P、K含量,改善大蒜植株的营养状况。两种氮肥水平下,大蒜地上部茎叶、蒜苔、蒜头和全株吸N、吸K及吸P量均随钾肥施用量的加大而提高。钾氮配施可促进磷素和钾素向蒜头的转移,从而提高P和K的再利用程度。     

钾氮配施对生姜产量和养分吸收的影响研究

1999～2001年在安徽省生姜产区淮北平原砂姜黑土上,连续三年多点开展钾氮配施对生姜产量及养分吸收的影响研究。结果表明:钾氮配合施用可以大幅度提高生姜的产量,施钾增产14.9～58.5%,平均增产率为29.8%。增施氮肥的增产效率为负数,钾肥的增产效率在两种氮肥水平下都较高,高N条件下增加钾肥施用量可以极大地提高钾肥的增产效率。施用钾肥提高了生姜地上部茎叶含氮量及茎叶、姜块和全株P、K养分含量,对全株氮素含量影响不大。两种氮肥水平下,生姜地上部茎叶、块茎和全株的吸K、吸N、吸P量都是随着钾肥施用量的增加而提高。钾氮配施大幅度提高了土壤有效P、K含量,有利于保持和提高土壤肥力。     

淮北砂姜黑土区氮钾配施对小麦产量及氮、钾养分吸收利用的影响

为给淮北砂姜黑土区小麦生产中氮、钾肥的科学施用提供理论与技术依据,采用田间试验研究了不同氮、钾水平(N:180、240、300、360 kg·hm~(-2);K:90、135、180 kg·hm~(-2))对小麦产量、氮钾养分吸收利用以及肥料效益的影响。结果表明:(1)N_(240)K_(180)处理下小麦产量为7 686 kg·hm~(-2),比低氮低钾(N_(180)K_(90))处理的小麦产量显著提高7.24%,与高氮高钾(N_(360)K_(180))处理的小麦产量无显著性差异;(2)氮、钾肥配比施用时两者存在正交互作用,该交互作用与小麦产量呈极显著正相关,对产量的贡献率为14.06%,且提高了氮、钾肥的偏生产力;(3)与低氮低钾(N_(180)K_(90))处理相比,N_(240)K_(180)处理下小麦植株体内氮、钾素含量分别提高14.67%和29.53%。综合考虑小麦产量和肥料效益,本研究条件下淮北砂姜黑土区适宜的氮(N)、钾(K_2O)肥施用量分别为240 kg·hm~(-2)和180 kg·hm~(-2)。     

氮钾配施对弱筋小麦氮、钾养分吸收利用及产量和品质的影响

在低钾和中钾土壤上,采用田间试验研究了氮钾配施对弱筋小麦氮、钾养分吸收及产量和品质的影响。结果表明,氮钾肥配合施用促进了弱筋小麦植株氮、钾含量的提高,氮、钾养分吸收表现出一定的正交互作用;合理配施氮钾肥能够显著地提高弱筋小麦产量。在低钾土壤上,N180K150处理产量最高(5023.kg/hm2);中钾土壤上,最高产量(5145.kg/hm2)为N180K90处理。两种土壤上,氮肥的产量效应均大于钾肥。低钾土壤上,氮钾对小麦产量表现出极显著的正交互作用。提高氮肥用量显著降低了弱筋小麦的专用品质,钾肥对小麦品质的独立效应不显著,但是钾对氮的品质效应存在着交互作用。弱筋小麦抽穗期或灌浆期植株氮、钾含量与子粒品质的相关系数较大,与产量的相关系数则是以拔节期或抽穗期较大。适当减少氮肥用量和增加氮、钾肥基施比例有利于改善弱筋小麦的品质。     

钾、氮配施对生姜产量和品质及钾素利用的影响

采用田间试验研究钾氮配施对生姜产量和品质及钾素吸收利用的影响。结果表明,不同K、N配施对生姜生长及品质有明显的影响,适宜的K、N用量及配合施用能明显促进生姜生长发育,增加根茎产量,改善营养品质,提高钾肥利用率。施钾量在450 kg/hm2以下,生姜根茎产量及产量构成因素随钾肥用量的增加而增加。两种氮肥水平下,株高、分枝数、茎粗及茎叶干重和单株姜根茎重均是中等钾肥用量K450处理最高,所有处理中N450K450获得了最高产量。品质分析结果显示,适宜的钾氮配施能有效提高生姜根茎维生素C和糖分含量,降低硝酸盐含量,改善营养品质。与不施钾的对照相比,施钾处理生姜根茎维生素C含量显著提高,以中等钾肥用量K450下最高;增加氮肥施用量对根茎Vc含量没有显著影响。施钾提高了生姜根茎可溶性糖和蔗糖含量,但不同钾氮配施处理提高幅度不同。K0和低钾条件下,增施氮肥会明显提高生姜根茎硝酸盐含量,施钾则能降低其含量;不同钾氮用量降低程度不同,适宜钾氮配施处理N375K375和N450K450硝酸盐含量最低。施用钾肥的处理,生姜茎叶、根茎和全株含K量明显提高,K素养分吸收量显著增多;同一钾肥用量下,增加氮肥用量,茎叶、根茎和全株含K量也明显提高,各部位K素积累量相应增加。钾素农学效率,低氮水平下随钾肥用量的增加而下降,高氮N450条件下,K450处理达最大值。钾肥利用率,两种氮肥水平下均是K450处理最高,高氮高钾的N450K525处理钾肥利用率也较高。     

不同肥料配施对土壤主要养分含量及作物氮、磷、钾表观利用率的影响

四年的分析结果表明，氮磷钾化肥配施有机肥和秸秆可明显提高土壤有机质，全氮、碱解氮，速效磷和速效钾含量，氮磷钾三元素化肥配施可明显提高土壤氮、磷、钾的含量和供给能力，单一施氮和氮，磷、钾三元素中的两两配合施入，可较明显地提高该配合所含养分在土壤中的含量，四年的分析结果还表明，含氮磷钾三元素配施的各处理总体上利用率较高。     

氮锌配施对作物产量、品质及养分吸收利用的影响研究进展

锌是作物生长必需的微量元素之一,在作物生长发育过程中起着至关重要的作用.但众所周知,锌肥施入土壤后有效性下降,利用率较低,提高锌肥有效性一直以来广受关注.而氮是作物生长发育所必需且需求量较大的营养元素,与锌元素具有协同效应,氮锌科学配施不仅可以提高锌肥有效性,也能提高氮肥利用率,并能促进作物生长和养分吸收,提高产量,但...     

氮硫配施对冬小麦氮硫吸收转运及利用效率的影响

采用二元二次正交旋转组合设计,通过田间试验研究了陕西关中地区氮硫配施对冬小麦氮硫素吸收、转运及利用效率的影响。试验施氮量[kg(N)·hm-2]设75(N1)、108(N2)、187.5(N3)、267(N4)和300(N5)5个水平,施硫量[kg(S)·hm-2]设75(S1)、97.5(S2)、150(S3)、202.5(S4)和225(S5)5个水平,组成N4S4、N4S2、N2S4、N2S2、N5S3、N1S3、N3S5、N3S1、N3S3 9个处理。结果表明:拔节期至开花期是冬小麦干物质和氮、硫积累的高峰期,积累量分别占全生育期内干物质和氮、硫积累量的43.33%~48.42%、28.71%~44.77%和40.11%~50.43%。氮素向籽粒的转运率(63.61%~70.64%)远高于硫素向籽粒的转运率(10.63%~30.98%);氮硫配施促进了小麦花后营养器官氮硫向籽粒的运转,同时增加了总转运量对籽粒氮硫的贡献率。在N2(108 kg·hm-2)和S2(97.5 kg·hm-2)水平,氮硫积累量及转运量随施硫量或施氮量的增加而增加;在N3(187.5 kg·hm-2)和S3(150 kg·hm-2)水平,则随施硫量或施氮量的增加先增加后趋于稳定。植株体内的氮素和硫素吸收累积量具有极显著相关关系。综合考虑氮素(硫素)表观利用率及生理效率,在施氮量(170.64~204.52 kg·hm-2)与施硫量(97.35~139.32 kg·hm-2)水平下,氮硫肥利用率较高。因此,在冬小麦栽培过程中,可以通过调节施氮量和施硫量,充分利用氮硫交互效应,提高氮硫的吸收、分配及利用效率。     

钾氮配施对生姜产量和品质的影响

通过多年田间试验研究淮北平原砂姜黑土地区钾氮配施对生姜产量和品质的影响。结果表明:增施钾肥对生姜的生长发育有明显的促进作用,施钾的增产幅度,杨集点狮子头姜为32.3％和33.3％,平均增产33.8％;牛庄柴姜增产32.8％和42.0％,平均增产35.6％;农场试验施钾增产37.8％～41.2％,平均增产率高达39.7％。钾氮配施能有效提高生姜块茎维生素C和可溶性糖分含量,显著降低硝酸盐含量,改善生姜的外观和内在品质,大幅度增加生姜产值,每公顷增收12155～13082元,施用钾肥的产投比高达34.9∶1和16.2∶1。当前生产水平下,淮北砂姜黑土地区生姜钾肥的适宜施用量为K2O 260～300kg/hm2,氮肥适宜用量为N 300kg/hm0左右。     

氮钾配施对莴笋产量和品质的影响

通过盆栽试验,探讨了石灰性褐土上氮与钾肥配施对莴笋(Lactuca sativa L. var. angustana Irish)产量和品质的影响。结果表明:单施适量氮肥对莴笋有一定的增产作用,但当每kg土氮用量超过0.30g时,反而导致减产。在施用氮肥的基础上配施钾肥,不仅能显著地提高莴笋产量,而且能明显减少施氮对品质造成的不利影响,氮、钾之间表现出良好的交互作用。     

施钾对木薯产量及钾养分吸收的影响

为探索施钾对木薯生长发育、钾含量、钾积累量及钾肥利用效率的影响,采用田间试验,以我国主栽品种SC205为材料,设K_2O用量0、120、240 kg/hm~2共3个水平,于不同生育期测定木薯叶片、茎秆、细根、块根的干物质量、钾含量,并在木薯收获期调查、测定农艺性状及块根鲜薯产量(FRY)。结果表明:(1)与不施钾相比,施钾显著提高木薯株高、叶面积、叶面积指数、叶绿素含量及鲜薯产量,增幅分别为16.1%~19.0%、3.8%~8.4%、12.8%~18.2%、13.6%~17.3%、12.8%~29.4%、9.9%~25.6%,其中,K_(120)处理产量最高,达27.1 t/hm~2;(2)施钾显著提高各组织钾含量及钾积累量,K_(120)和K_(240)处理间的钾积累量无显著差异;不同组织钾含量表现为叶片茎秆细根块根;随生育期推进,钾素积累的主要组织由叶片向茎秆和块根转变;(3)木薯钾肥效率、钾素生理效率、钾素利用效率、钾素收获指数均随施钾量增加而显著降低,100 kg鲜薯需钾量随施钾量增加显著提高。综合木薯产量、钾积累量、钾肥利用效率等指标综合分析,建议木薯施钾量为120 kg/hm~2。     

不同生育时期根际土壤渍水逆境对冬小麦N、P、K素营养的影响

运用盆栽模拟土壤渍水逆境试验，研究不同生育时期根际土壤渍水逆境对不同小麦品种N、P、K素吸收、运转和分配的影响。结果表明，根际土壤渍水逆境对不同小麦品种N、P、K素吸收的影响有异;不同生育时期根际土壤渍水逆境显著影响根系对N、P素的吸收、运转与分配，以孕穗期渍水逆境影响最大，其次为灌浆期和拔节期，而不同生育时期根际土壤渍水逆境对K素的吸收影响较小。孕穗期以前浈水逆境主要影响小麦根系对N，P，K案的吸收．对N、P、K素在小麦体内的运输和分配影响较小；灌浆期渍水逆境不仅影响根系对N、P、K素的吸收．同时也影响N、P素在地上部各器官中的运转和分配，但对K素在小麦体内的运转和分配影响较小。因此，基肥中施足P肥和K肥，拔节孕穗期重施速效N肥，灌浆期叶面喷施KH2PO4对于培育壮秆大穗，减轻小麦溃害，提高受渍小麦籽粒产量具有非常重要的实际意义。     

Optimum Nitrogen Fertilization of Winter Wheat Based on Color Digital Camera Images

Abstract

Site‐specific nitrogen (N) fertilizer management based on soil N_min (soil mineral N) and the plant N status (sap nitrate analysis and chlorophyll meter (SPAD) reading test) has been shown to be effective in decreasing excessive N inputs for winter wheat in the North China Plain, but the multiple sampling of soil and plants in individual fields is too time‐consuming and costly for producers and farmers. In this study, a color digital camera was used to capture wheat canopy images at a specific growth stage to assess N needs. Treatments included a farmer's N treatment (typical farmer practice), an optimum N treatment (N application based on soil–plant testing), and four treatments without N (one to four cropping seasons without any N fertilizer input). Digital images were analyzed to get red, green, and blue color‐band intensities for each treatment. Normalized intensities of the red, green, and blue color bands were well correlated with soil N_min, SPAD readings, sap nitrate concentration, and total N concentration of winter wheat. This research indicated the potential of using a digital camera as a tool combined with an improved N_min method to make N fertilizer recommendations for larger fields.     

氮磷钾硫的施用对冬小麦光合特性及产量的影响

试验于河南农业大学科教示范团区进行，以强筋小麦豫麦34为试验材料，研究了氮磷钾硫对小麦光合特性及籽粒产量的影响。结果表明，在本试验范围内，氮磷硫肥用量对强筋小麦群体光合速率、叶绿素含量和硝酸还原酶活性均具有明显的调节作用，各因子不同供给水平对光合特性指标的影响均表现为随施用量的增加而提高，但于花后不同时期处于主导地位的肥料因子有所不同。氮磷钾硫配施对籽粒产量也有明显的调节作用，硫氮对产量的影响达到极显著水平，是影响冬小麦产量的最大因子，而磷肥、钾肥对产量影响不显著，N70P120K180S30是最佳水平组合。     

Nitrogen,Phosphorus and Potassium Fertilization Interactions on the Photosynthesis of Containerized Citrus Nursery Trees

The objective of this research was to evaluate the nitrogen, phosphorus and potassium (NPK) fertilizer effect on the development of ‘Valencia’ sweet orange nursery trees budded on Rangpur lime rootstocks in a greenhouse using containers. The experiment was a complete (1/5) 5³ factorial randomized blocks design. Treatments comprised five concentrations (g per plant) of N (1.25; 6.25; 11.25; 16.25; 21.25); K (0.42; 3.75; 6.22; 9.34; 12.45); and P (0.19; 0.89; 1.59; 2.29; 2.99). Carbon dioxide assimilation rate (A), transpiration rate (E), stomata conductance (g_s), and internal carbon dioxide (CO₂) concentration (Ci) and water use efficiency (WUE). Reducing sugar, sucrose and starch were evaluated. Response functions were adjusted and nutrient rates for maximum yield were presented. The results indicated that the high levels of N (>16.25 g per plant) interferes negatively on photosynthesis. Potassium at intermediate fertilization levels (from 3.75 to 6.22 g per plant) had positive effects on photosynthesis. But P had little interference on photosynthesis. Carbohydrates levels were not related to nutrients fertilized.     

Assessing Nitrogen Fertilization Strategies in Winter Wheat and Cotton Crops in Northern Greece

The management of fertilizer application is crucial for agricultural production and environmental safety.The objective of this study was to assess the effciency of different fertilization strategies,applying fertilizers with and without nitrification inhibitors(NIs) in split application,in Greece.The assessment criteria used were based on crop yield,soil nitrogen(N)concentrations and economic effciency.For this purpose two crops(winter wheat and cotton)were seffected in order to explore the optimum fertilization strategy for each crop.Three treatments combining fertilizers with NIs were tested compared with conventional fertilization(CF).Slight differences in the quantity and the combination of fertilizers with NIs applied resulted in variable effects on crop yield,soil N and economic return.Split N application of 102 kg ha^-1,with half of the total amount applied at seeding,resulted in higher grain yield of winter wheat,lower NO₃^--N in soil and higher economic return.This result reveals the importance of N application at seeding in wheat crop.Fertilization strategy with 109.5 kg N ha^-1 and split P application resulted in higher cotton yield and higher economic profit.Split P application seemed to increase yield,even though it is not a common practise in the area.     

Winter Wheat Quality Responses to Water,Environment, and Nitrogen Fertilization

Decreasing carbon (C) footprints by reducing nitrogen (N) and water inputs has been speculated to have negative impacts on wheat grain yield and flour processing quality. The objective of this study was to determine the impact of N and water stress on winter wheat grain yield, protein composition, and dough quality. Wheat fertilized at two N rates (unfertilized and recommended) was grown under water-stressed and well-watered environments. Nitrogen and water stress were measured using the ¹³C isotopic approach. Research showed that (1) N fertilizer and the water-management environment produced similar impacts on wheat quality and yield loss due to N stress and yield loss due to water stress (YLWS); (2) N fertilizer increased flour protein, dough stability, and relative concentration of glutenin (%Glu), unextractable polymeric protein (UPP), and relative amount of high-molecular-weight glutenin subunits (HMW-GS/LMW-GS); (3) the well-watered environment reduced protein contents when N mineralization was low, whereas it did not influence protein content when mineralization was high; and (4) the %Glu was negatively correlated with yield loss due to N stress (YLNS) and positively correlated with stability. This study showed that a clear understanding of the complex relationship between soil variability and climatic conditions should make it possible to develop adaptive management practices, increase profitability, and improve quality.     

Effect of Different Fertilization Methods and Nitrogen Doses on the Weediness of Winter Wheat

The field study was conducted in April 2006 in a long-term fertilization experiment that was set up in 1983. The aims of this study are to compare the weediness in plots with nitrogen–phosphorus–potassium (NPK), NPK + farmyard manure (FYM), and NPK + stalk treatments and to study the effect of increasing N doses on the weeds and winter wheat plants. The bifactorial test was arranged in a split-plot design with three replications. The treatments were the following: 0, 50, 100, 150, and 200 kg ha^?1 N, 100 kg ha^?1 phosphorus pentoxide (P₂O₅), and 100 kg ha^?1 potassium oxide (K₂O). Three weed species were dominant in the experiment: Veronica hederifolia, Consolida regalis, and Stellaria media. The NPK treatment resulted in the smallest average weed cover. The significantly greatest weed cover was found on the plots treated with NPK + FYM, but the greatest biomass production of winter wheat was measured also in the NPK + FYM treatment, which resulted in a good crop competition. The weed cover was increased proportionally by the rising N doses. The effect of increasing N rates was positive on the winter wheat biomass and on wheat competition to the weeds. Results of our study show that we can manage weeds better using favorable plant nutrition.     

测墒补灌和施氮对冬小麦产量及氮素吸收分配的影响

采用田间试验裂区设计方法,研究了测墒补灌和施氮对冬小麦产量及氮素吸收分配的影响。补灌设3个水平,在冬小麦拔节期0—40cm土层补灌至土壤目标相对含水量的60%(W_1),70%(W_2)和80%(W_3)。施氮设3个水平:不施氮(N_0)、施纯氮195kg/hm~2(N_(195))和255kg/hm~2(N_(255))。结果表明:(1)不同补灌和施氮对冬小麦关键生育期株高、叶面积影响效果较为显著,同一补灌处理下,其冬小麦株高、叶面积均表现为N_(255)N_(195)N0(p0.05)。N_(195)、N_(255)处理显著高于N_0处理,但N_(195)及N_(255)处理间无显著性差异(p0.05),同一施氮处理下,W_2(569.4m~3/hm~2)、W_3(873.45m~3/hm~2)处理显著高于W_1(265.2m~3/hm~2)处理,但W_2及W_3处理间无显著性差异(p0.05)。说明过量施氮和补灌对冬小麦株高、叶面积无显著性作用。(2)同一施氮水平下,补灌对冬小麦的增产效应随施氮量的增加呈下降趋势,说明施氮和补灌对冬小麦产量存在一定的临界值,超过临界值,产量下降。当施氮量为195kg/hm~2,补灌量为田间持水量的70%(569.4m~3/hm~2)时达最高产8 500kg/hm~2。(3)冬小麦成熟期,施氮处理的植株氮素积累量显著高于不施氮处理(p0.05),但在W_2、W_3处理下,N_(255)相较于N_(195)显著下降(p0.05),特别是在W_3(873.45m~3/hm~2)水平下,N_(255)甚至低于N_0处理;在N_0、N_(195)处理下,植株氮素积累量随补灌量的增加显著增加(p0.05),但在N_(255)处理下并无显著差异(p0.05),说明适量补灌、施氮可提高冬小麦的吸氮能力,但过量补灌、施氮并不利于植株对氮素的吸收。(4)拔节期补灌量的增加虽提高了冬小麦的吸氮能力,促进冬小麦吸收较多的氮素,却抑制了冬小麦体的氮素向籽粒的转移和分配。综合考虑冬小麦生长状况及氮素风险状况,建议施氮量为195kg/hm~2、补灌至田间持水量的70%(569.4m~3/hm~2),作为该区域适宜的水、肥用量。     

不同施肥下冬小麦生长过程中土壤矿质氮变化及其与冬小麦叶片SPAD值的关系

通过调查分析,研究了土长期施肥条件下土壤中矿质氮含量变化及其与地上冬小麦叶片SPAD值。结果表明:(1)整个冬小麦生长期不同土层硝态氮和铵态氮的变化趋势不一致,硝态氮含量是先下降后上升的变化,而铵态氮含量呈一直上升的变化趋势。在没有施过氮肥的处理中,0—20cm,20—40cm土层中土壤硝态氮、铵态氮含量显著低于施用氮肥的处理;(2)冬小麦生长时期,各个处理叶片SPAD值各异,但都是先升高后下降的变化,无氮肥施用的叶片SPAD值低于施氮肥的处理;(3)冬小麦各个生长时期叶片SPAD值与土壤不同层次(0—20cm,20—40cm)硝态氮含量呈正相关关系,而与铵态氮含量相关性不显著,这表明小麦是对硝态氮较为敏感的作物。本试验结果可以为进一步合理调控氮肥施用、明确施氮对小麦产量和品质的影响提供一定的基础依据。