氮肥减施对宽幅播种冬小麦产量形成和氮肥利用效率的影响

为明确氮肥减施对宽幅播种冬小麦产量和氮肥利用效率的影响,设置氮肥减施(减肥处理)、农户习惯施肥量(习惯施肥处理)、不施氮(无肥处理)3个处理,通过大田试验研究了不同处理冬小麦的群体动态、干物质积累特征、产量及其构成和氮肥利用效率的影响。结果表明,无肥处理的产量比习惯施肥处理低36.83%,而减肥处理的产量比习惯施肥处理高6.01%。无肥处理的最大茎蘖数显著低于习惯施肥处理,导致亩穗数和收获期生物量显著低于习惯施肥处理。减肥处理的最大茎蘖数也显著低于习惯施肥处理,但由于成穗率显著提高,亩穗数和收获期生物量与习惯施肥处理无显著差异。无肥处理的有穗单茎花后干物质积累量、花后干物质对籽粒的贡献率与习惯施肥处理无显著差异。而减肥处理的花后干物质积累量、花后干物质积累对籽粒的贡献率比习惯施肥处理分别显著提高39.70%和14.51个百分点。减肥处理的地上部氮吸收量与习惯施肥处理无显著差异,但氮收获指数提高2.97%,氮肥农学效率提高12.94%,氮肥偏生产力提高41.09%,氮肥利用率提高11.90个百分点。上述试验结果表明,宽幅播种配合氮肥减施可通过降低最大茎蘖数,提高成穗率,促进花后干物质积累及向籽粒分配,提高氮肥利用效率和产量。本研究为宽幅播种冬小麦实行氮肥减施提供了科学依据。     

宁夏引黄灌区春小麦不同生育期吸收氮、磷、钾养分的特点

选择宁夏引黄灌区中等肥力灌淤土,设置施肥与不施肥处理,在相距约5km的3个试验点进行了肥料田间试验,研究春小麦不同生育期氮、磷、钾养分的吸收特点。结果表明,在供试土壤条件下,施肥可明显提高小麦产量、干物质累积量、体内氮、磷、钾含量及其累积量。施肥或不施肥,小麦地上部干物质的累积量随生育期呈典型S型曲线增长,其中拔节期和灌浆期出现两个高峰期,各占总累积量的30%左右。植株氮、磷、钾含量随生育期呈曲线下降趋势,特别是从拔节到灌浆中期下降幅度较大;而在分蘖期以前和灌浆中期以后变化幅度较小。植株氮、磷、钾累积吸收量随生育期的延长和施肥水平的提高而增加,但各生育期相对累积吸收比例,施肥与否差异不大。苗期氮、磷、钾的吸收量约占总吸收量的4%～5%,分蘖期占20%～23%,拔节期分别占30%、41%、34%,抽穗期分别占14%、12%、10%,灌浆期分别占29%、20%、26%,成熟期占1%～3%,其中拔节期是养分吸收的高峰时期。不论施肥与否,地上部氮、磷、钾累积吸收量与其干物质累积量之间均呈极显著正相关,而与植株氮、磷、钾含量之间呈极显著负相关。     

减氮控磷稳钾施肥对水稻产量及养分积累的影响

氮、 磷用量偏大,钾肥用量不足不仅影响水稻的正常生长发育,而且导致养分利用率偏低。本文通过田间试验,研究减量施用氮、 磷肥,稳定钾肥投入对水稻产量、 养分积累量和肥料利用率的影响。试验设14个处理,每个处理重复2次。结果表明,氮钾、 磷钾、 氮磷钾配施处理的水稻秸秆生物量和籽粒产量均显著高于不施肥处理（P0.05）; 减氮控磷稳钾处理（N 225 kg/hm2、 P2O5 60 kg/hm2、 K2O 90 kg/hm2）与常规施肥处理相比（N 300 kg/hm2、 P2O5 150 kg/hm2、 K2O 60 kg/hm2）能显著增加水稻秸秆生物量（P0.05）,明显提高千粒重和籽粒产量; 试验还得出,减氮控磷稳钾处理分蘖期地上部氮、 钾含量和秸秆氮、 钾含量显著高于常规施肥处理（P0.05）; 收获期地上部氮、 钾的积累量和氮、 磷的表观利用率显著大于常规施肥处理（P0.05）。适当减少氮、 磷用量, 增加钾肥用量能改善氮、 钾营养状况,促进地上部干物质的积累,提高籽粒产量和氮、 磷表观利用率。N 196.2 kg/hm2、 P2O5 46.5 kg/hm2、 K2O 90 kg/hm2的配施方案具有实际推广应用价值。     

花生补灌条件下施氮对土壤氮素吸收与转化的影响

为提高辽西地区花生产量和水氮利用率,本文以‘白沙1016’为对象,采取裂区试验,主区为雨养(W0)和测墒补灌(W1)两种灌溉模式,子区为0 kg·hm~(-2)(N0)、40 kg·hm~(-2)(N1)、60 kg·hm~(-2)(N2)和80 kg·hm~(-2)(N3)4个施氮水平,研究施氮对测墒补灌条件下花生干物质积累和氮素积累及分配的影响。试验结果表明:在雨养和测墒补灌条件下,花生成熟期的单株干物质量分别为64.66~74.92 g和71.65~92.81 g,以W1N3处理最高,W0N0最低,且随施氮量呈现二次曲线变化趋势。花生植株氮积累量随施氮量变化趋势与干物质量一致,W1N2较其他处理显著提高了氮素积累量、产量和水分利用效率。测墒补灌优化了花生植株中氮素的分配,延长了叶片氮素积累时长,同时提高了叶片氮素向荚果的转移量,继而相对雨养处理显著增加了花生荚果氮积累量所占植株氮积累总量的比重(氮收获系数)2.13%、氮肥农学利用率78.57%、氮肥表观回收率25.90%。花生收获后,土壤硝态氮主要分布在0~40 cm土层内,占0~60 cm土层的77.75%,且累积量随着施氮量的增高而增加,但补灌会使土壤硝态氮下移造成硝态氮淋失。因此,综合考虑水氮利用效率,在辽西半干旱地区推荐W1N2为适宜花生生产水氮管理,其产量、水分利用效率和灌溉水利用效率最高,分别为6 485.03 kg·hm~(-2)、2.02 kg·m~(-3)和10.21kg·m~(-3)。     

氮肥配施添加剂NAM对甜瓜生长、养分利用和产量品质的影响

通过田间试验,研究NAM添加剂在甜瓜减氮施肥的情况下,对甜瓜生长、养分吸收及产量品质的影响,旨在验证利用NAM添加剂减少当地甜瓜施氮量的可行性。以新疆主栽甜瓜品种"黄皮9818"为材料,2年田间试验共设5个处理:常规施氮量(N)、常规施氮量添加NAM(N+NAM)、80%常规施氮量添加NAM(80%N+NAM)、不施氮添加NAM(N_0+NAM)、不施肥(CK),分析了甜瓜干物质、植株养分吸收利用效率、产量及品质。成熟期,与N处理相比,N+NAM处理显著提高干物质积累量及产量,分别提高4%和7.7%;而N处理与80%N+NAM处理干物质量和产量无显著差异。甜瓜各器官氮、磷、钾含量均表现为瓜叶茎,整株养分吸收量为钾氮磷;与各器官养分吸收量表现一致,N+NAM处理整株氮、磷吸收量显著高于其他处理5%～40%、5.5%～39%,氮肥表观利用率、生理利用率均以氮肥添加NAM处理最高,其中N+NAM、80%N+NAM处理氮肥表观利用率分别比常规施氮量处理(N)提高5.3%、4.9%。折光糖含量在3个施氮处理间差异不显著。与常规施氮处理的多次施肥相比,减氮20%添加NAM甜瓜产量和品质没有降低,并且提高了氮肥表观利用率。因此,在甜瓜生产中,减氮20%添加NAM是甜瓜施肥减施增效的有效途径。     

稻-麦轮作体系不同施肥模式对氮肥利用效率和土壤有效养分平衡的影响

土壤肥力和养分利用效率是保障可持续粮食生产的基础。通过田间试验研究了稻—麦轮作体系下不同施肥模式氮肥利用效率和土壤有效养分的变化,结果表明:在减少养分总投入量的条件下,有机肥部分替代化肥处理(RF-OM和RF-S处理)水稻地上部总生物量显著高于LRF处理(P<0.05),与FP处理差异不大;小麦秸秆生物量与FP和LRF处理差异均不显著,籽粒生物量及地上部总生物量与LRF处理相差不大。水稻收获期RF-OM处理地上部主要器官含氮量与LRF处理差异不显著,氮素积累总量显著高于LRF处理(P<0.05);小麦收获期RF-OM和RF-S处理秸秆、籽粒含氮量和氮素积累量与LRF处理均无显著差异。收获期RF-OM和RF-S处理水稻糙米和稻壳、小麦秸秆和籽粒含磷量及磷素积累量与FP和LRF处理差异都不大;水稻秸秆、稻壳及小麦秸秆含钾量和钾素积累量均显著高于FP和LRF处理(P<0.05)。有机肥部分替代化肥处理水稻、小麦氮肥农学利用率、氮肥表观回收率和氮肥偏生产力与FP和LRF处理相比均显著提高(P<0.05),氮素籽粒生产效率也高于FP和LRF处理,甚至达到显著水平(P<0.05)。试验表明,水稻、小麦收获期增钾处理(RF-OM和RF-S处理)土壤速效钾、缓效钾含量显著高于FP和LRF处理(P<0.05),水稻收获期土壤碱解氮和小麦收获期土壤有效磷含量与LRF处理差异不大,同时,经1个稻—麦轮作周期后,4个施肥处理土壤有效养分(碱解氮、有效磷、速效钾、缓效钾)含量均高于供试土壤。有机肥部分替代化肥能显著提高稻麦氮肥利用效率,有利于土壤有效养分平衡,并显著提高土壤速效钾和缓效钾养分含量,是适宜的稻麦化肥减量和稳产增效施用技术。     

滴灌施磷对甜菜磷养分吸收及磷肥利用率的影响

采用随机区组设计,以塔额盆地主栽甜菜品种 (Beta796)为试验材料开展大田试验。在氮、钾施用量相同的情况下,设置滴灌施磷(P2O5)0 kg·hm-2(P0)、120 kg·hm-2(P1)、180 kg hm-2(P2)和240 kg·hm-2(P4)4个处理,研究甜菜主要生育时期磷养分吸收、积累和分配规律,分析甜菜磷养分利用效率,以期为甜菜高产、优质、高效生产中磷肥管理提供理论依据。结果表明,滴灌施磷能增加甜菜干物质积累量,P1、P2和P3处理干物质积累量较P0处理分别增加16.6%、24.7%和27.9%,其中P2、P3处理间差异不显著。甜菜干物质积累Logistic方程显示施磷能显著提高甜菜干物质最大累积速率和平均积累速率,最高分别可达443.7和185.7 kg·hm-2·d-1。甜菜磷积累总量随施磷增加而增加,有利于提高生育后期甜菜磷积累量,尤其是甜菜地下部的磷积累量;收获期P3处理地下部磷积累量为74.25 kg·hm-2,较P0、P1和P2处理分别显著增加76.7%、24.8%和12.1%。施磷对收获期甜菜磷素在地上部、地下部分配无显著影响。试验结果表明滴灌施磷显著提高了甜菜产量,增加了甜菜块根的含糖量及产糖量。 P1、P2和P3处理块根产量比P0处理分别增加11.57%、18.58%和20.89%,甜菜蔗糖含量比P0处理分别增加1.18%、2.90%和3.37%。施磷对甜菜品质影响不大。施磷增加了磷肥的当季利用率,不同处理磷肥利用率可达31.54%～39.66%。P2处理能增加磷素农学效率,磷肥偏生产力则随着施磷量增加而减少。综合甜菜相对产糖量、经济效益及磷肥利用效率,滴灌施磷(P2O5)85.1～187.4 kg·hm-2,可以实现甜菜高产和磷肥高效利用的目的。     

红芸豆养分限制因子及养分吸收、积累和分配特征研究

研究红芸豆养分限制因子、植株干物质和氮、磷、钾养分积累及分配规律,可为红芸豆合理施肥及高产栽培提供理论依据。大田试验条件下,以‘英国红’红芸豆为试材,设置缺素试验,采集全施肥区植株样品,分析研究红芸豆不同生育时期各器官干物质量、养分含量及积累量。结果显示,氮磷钾配合全施显著提高红芸豆产量;缺氮、缺磷、缺钾处理与全施肥处理相比,产量分别降低14.2%、8.0%和11.3%,表明影响红芸豆产量的限制因子为氮钾磷。在整个生育期,红芸豆干物质累积速率先升高后降低;根、茎、荚皮和豆粒干物质累积量呈上升趋势,叶干物质在收获期有下降趋势,收获时不同部位干物质量为豆粒茎≈荚皮叶片根。随生育期推进,茎、叶和荚皮中氮含量呈递减趋势,豆粒中氮含量呈递增趋势,而各器官磷、钾含量呈递减趋势。盛花期到结荚期是养分累积最大期,其氮、磷、钾吸收量分别占整个生育期吸收总量的28.14%、49.22%和56.20%;不同器官吸收累积氮、磷、钾量不同,成熟期豆粒、叶、茎和根中均为累积氮最多、钾次之、磷最少,荚皮中累积钾最多、氮次之、磷最少。每生产100 kg红芸豆需供给N 4.37 kg、P2O5 2.38 kg、K2O 3.53 kg,比例为1∶0.54∶0.81。     

一次性施肥对长江中游春玉米产量及养分利用效率影响

通过大田试验,研究了一次性施肥方式对长江中游春玉米产量及养分吸收、转运和利用的影响。研究结果表明,一次性施肥方式与农民常规施肥方式相比,产量差异不显著,经济效益提高1429~1725 Yuan/hm2。一次性施肥方式降低春玉米花前干物质积累量,但中后期干物质积累速率加快,全生育期内春玉米干物质积累量及花后干物质对产量贡献率,与农民习惯施肥方式差异不显著。与农民习惯施肥相比,一次性施肥显著降低了春玉米生育前期（拔节期）氮、磷、钾素积累量,生育中后期玉米养分积累速率加快,成熟期氮、磷、钾素积累量差异不显著;一次性施肥方式对春玉米氮素转运和利用效率的影响不显著;一次性施肥减少磷素和钾素的投入,但并不影响春玉米整个生育期磷素和钾素的积累和转运,同时显著提高了磷素和钾素的养分利用效率。     

控释尿素不同条施深度下鲜食玉米产量和氮素利用效应

通过田间试验研究一次性施肥条件下控释尿素不同条施深度(0,5,10,15cm)对鲜食玉米产量、干物质积累变化、氮素利用率和土壤无机氮含量的影响,为控释尿素在鲜食玉米上的应用推广提供依据。结果表明:控释尿素施用深度的不同主要影响鲜食玉米抽雄至乳熟收获期的干物质积累,该阶段10,15cm深度下鲜食玉米的干物质积累速率和积累量显著高于0,5cm。随着控释尿素施用深度的增加,鲜食玉米鲜穗产量、乳熟收获期植株总吸氮量以及氮肥偏生产力、氮肥农学利用效率和氮肥表观利用率均呈现递增趋势,与0cm相比,15cm深度处理的鲜穗产量和收获期植株总吸氮量分别显著提高13.3%和53.0%,氮肥偏生产力从70.9kg/kg增加到80.4kg/kg,氮肥农学利用效率从6.8kg/kg增加到16.3kg/kg,氮肥表观利用率从3.3%提高到33.7%;10cm深度处理仅较0cm处理显著提高了植株总吸氮量和氮肥表观利用率,而5cm深度处理的鲜穗产量、乳熟收获期植株总吸氮量、氮肥偏生产力、氮肥农学利用效率和氮肥表观利用率与0cm处理间均无显著差异。抽雄期叶片光合特性测定结果表明,与不施氮(CK)相比,控释尿素的施用显著提高了单株叶面积、叶面积指数和穗位叶净光合速率,与0cm相比,15cm深度处理的单株叶面积、叶面积指数、叶片净光合速率、蒸腾速率和胞间CO2浓度均有不同程度的提高。关键生育期的土壤无机氮测定结果表明,控释尿素施用深度的增加可以提高拔节期、抽雄期和乳熟收获期行间(施肥部位)0—20cm土层、抽雄期和乳熟收获期行间(施肥部位)20—40cm土层以及乳熟收获期玉米种植行(非施肥部位)0—20cm的土壤无机氮含量。可见,控释尿素深施能够提高鲜食玉米抽雄期以后的土壤供氮能力和改善叶片光合特性,促进干物质积累和氮素吸收,从而提高氮肥利用率和鲜穗产量。试验设置条件下,控释尿素最佳的施用深度为15cm。     

Pulp Fiber Residue and Supplemental Irrigation on Yield and Nutrient Uptake of Potato

ABSTRACT

Organic matter levels combined with drought periods during the growing season have adverse impacts on rain-fed potato production in coarse textured soils of eastern Canada. Using pulp fiber residues (PFR) may build up soil organic matter, improve crops yield and nutrient uptake, and reduce the need for supplemental irrigation in this region. A box experiment with 3 rates of PFR [0, 45, and 90 Mg ha^{? 1} dry mater carbon (C) basis] with or without supplementary drip irrigation was established in a sandy loam soil in New Brunswick, Canada. Red clover, barley, and potato were cultivated as three crops of the rotation in 1999, 2000, and 2001, respectively. The PFR only applied before red clover in fall 1998. Selected soil chemical and physical properties were measured before planting and after harvest. Crops yield and nitrogen (N), phosphorus (P), and potassium (K) accumulation were determined at harvest. Soil organic-C content, bulk density and water holding capacity were improved by PFR application. Red clover and barley biomass production were significantly increased by PFR application. This effect was promoted by supplemental irrigation. Potato tuber yield was not affected by PFR and it was higher in rain-fed compared to supplementary irrigated system. Although, there was some initial evidence of N immobilization but generally PFR application increased N, P, and K bioavailability. This research has demonstrated that PFR can successfully be used as soil amendment in coarse textured soils without any adverse effect.     

补充灌溉及氮磷配施对黄土塬区冬小麦水分利用及产量的影响

采用裂区试验设计,对黄土塬区补充灌溉及氮磷配施条件下麦田土壤水分动态、作物产量及水分利用效率等进行研究。结果表明：1）冬小麦对土壤水分的利用深度随小麦生长发育逐渐加深,在越冬前期和孕穗期分别达1.2和2.2 m土层以下,不同处理土壤含水量在小麦生育前期差异不明显,孕穗后氮磷配施处理的土壤含水量显著低于不施肥处理;2）试验条件下,补充灌溉后同样施肥处理的作物产量与雨养相比,虽有增加但不显著;不论是雨养水平,还是补充灌溉水平,氮磷配施均表现出显著的增产效果,从低氮低磷到高氮高磷,增产幅度在134%到240%之间;3）氮磷配施能显著提高冬小麦水分利用效率,而补充灌溉后水分利用效率降低3%-30%,但未达显著水平;4）不同氮磷配施的增产效应高于补充灌溉,补充灌溉与高氮高磷处理有显著的水肥协同效应,能显著提高作物产量并保持较高的水分利用效率。     

How do AMF-inoculation and supplemental irrigation affect the productivity of rainfed yellow sweet clover in agrisilviculture systems?

ABSTRACT

Yellow sweet clover (Melilotus officinalis L.) was assessed for its yield in an agri-silvicultural model of the plum (Prunus domestica (L.) cv. Opal). The treatments included two sun light exposures (morning light and afternoon light) as main plots and species of arbuscular mycorrhizal fungi (AMF) (Funneliformis mosseae, Rhizophagus irregularis and no-AMF-inoculated control) as subplots. The treatments were separately arranged for two irrigations (rainfed and supplemental irrigation) during 2016–2017. In irrigated and AMF-inoculated plants, a significant increase was observed in the performance of yellow sweet clover (dry weight and biological yield), seed nutrients (phosphorus and potassium) and weight of aerial parts in morning light conditions as much as rainfed conditions, identically for two species of fungi. In both rainfed and supplemental irrigations, the biological yield of F. mosseae inoculated plants increased by up to 23%. In supplemental irrigation, the maximum growth of plant height and relative water content were obtained from AMF-inoculated plants (R. irregularis) in afternoon light area as much as rainfed condition. In conclusion, the identical beneficial effects of mycorrhizal fungi species were enhanced by single supplemental irrigation. However, plant performance, including the quality and quantity of yield, was superior in the morning light part of each treatment.     

沙地滴灌春玉米最适氮磷钾配方施肥研究

探索沙地春玉米(Zea mays L.)最适滴灌施肥方案是提高其产量和生物量积累的有效途径。采用三因素D饱和最优设计试验,研究了不同氮磷钾配方施肥对玉米产量及拔节期、抽雄期和收获期玉米干物质量的影响,结果表明:(1)氮磷钾不同配施可提高产量32.60%~52.90%;产量方程和两因子互作效应分析表明,氮磷钾配施有效提高产量,氮肥增产效果最明显,钾肥其次,磷肥最小,产量随肥料施用量增加呈现先增加后降低的趋势。(2)氮磷钾配施对干物质量和收获指数的影响显著,3个生育期干物质量最大的处理、收获指数最高的处理均为氮磷钾配施处理。(3)在覆膜滴灌条件下,根据对玉米产量及各生育期干物质量分析表明:沙地玉米最佳施肥方案为氮肥240 kg·hm^-2、磷肥80 kg·hm^-2、钾肥225 kg·hm^-2。     

不同滴灌施肥模式对棉花产量及养分吸收的影响

通过等养分和等成本施肥田间试验,研究不同滴灌施肥模式对棉花产量及养分吸收的影响。试验设4种滴灌施肥模式,分别为常规基施(CK)、常规追施(DCK)、普通滴灌专用肥(F1)和高磷钾滴灌专用肥(F2)。结果表明,在等养分施用条件下,高磷钾滴灌专用肥和普通滴灌专用肥处理的棉花干物质重、养分吸收量和产量均显著高于常规基施处理,但普通滴灌专用肥和常规追施处理差异不大;常规基施处理的氮肥和磷肥的利用率最低,普通滴灌专用肥和常规追施处理的氮肥和磷肥利用率差异不显著,高磷钾滴灌专用肥可显著提高磷肥利用率。在等成本施用条件下,常规追施处理的棉花干物质重、养分吸收量和产量最高,而高磷钾滴灌专用肥、普通滴灌专用肥和常规基施处理无显著差异。因此,滴灌专用肥尤其是高磷钾滴灌专用肥具有较好的应用效果,但是如何降低肥料成本是滴灌专用肥技术面临的重要问题。     

Crop Productivity and Nutrient Bioavailability in a Potato-Based Three-Year Rotation as Affected by Composted Pulp Fiber Residue Application and Supplemental Irrigation

The possibility of using composted pulp fiber residues (CPFR) in a potato rotation in eastern Canada was tested. Three rates of CPFR (0, 45, and 90 Mg C ha^?1) with or without supplementary irrigation were applied. Pea (Pisum sativum L.), corn (Zea mays L.), and potato (Solanum tuberosum L.) were cultivated in 2002, 2003, and 2004, respectively. Soil total carbon (C) and nitrogen (N), bulk density, and water-holding capacity were improved by CPFR. Pea and corn yields and total dry matter were increased using CPFR. Supplemental irrigation increased pea yield compared with the rain-fed system. Total tuber yield was increased by CPFR in the irrigated but not in the rain-fed system. The CPFR application increased plant-available phosphorus (P) and potassium (K) in all rotation crops. Nitrogen accumulation in all rotation crops except potato was increased by CPFR. The CPFR application successfully enhanced soil fertility and crop productivity without any adverse effects.     

Efficiency of Potassium Fertilization and Salicylic Acid on Yield and Nutrient Accumulation of Sugar Beet Grown on Saline Soil

Rising soil salinity has been a major problem in the soils of Egypt in recent decades. Potassium fertilization and salicylic acid (SA) play an important role in promoting plants to tolerate salt stress and increased the yield of sugar beet crop. A field experiment on sugar beet (Beta vulgaris L.) grown on saline soil was carried out during 2014 growing season in Port Said Governorate, Egypt, to study the effect of potassium fertilization of the soil at applications of 0, 100, 150, and 200 kg potassium (K) ha^?1 and foliar spray of SA by solution of 1000 mg L^?1, twice (1200 L ha^?1 each time) on yield and nutrient uptake. Application of 200 kg K ha^?1 in combination with salicylic foliar spray gave the highest root length, root diameter, shoot and root yield, sucrose, juice purity percentage, gross sugar yield, and white possible extractable sugar, nitrogen (N), phosphorus (P), and potassium (K) content, and uptake of sugar beet. The highest increase in sucrose (20%) as well as white possible extractable sugar (184%) was obtained by 200 kg K ha^?1 in combination with salicylic foliar spray compared with untreated soil with potassium fertilization and without salicylic foliar spray.     

膜下滴灌水肥耦合促进番茄养分吸收及生长

研究膜下滴灌不同水肥调控措施对日光温室番茄生长、产量、养分吸收利用的影响,为温室番茄水肥科学管理提供依据。设灌水(W)和施肥(F:N-P2O5-K2O)2因素,以常规沟灌施肥(W1:100%ET0,F1:240-120-150kg/hm2,ET0为参考作物蒸发蒸腾量)为对照(Control,CK),3个滴灌水量(W1:100%ET0、W2:75%ET0、W3:50%ET0)和3个施肥水平(F1:240-120-150 kg/hm2、F2:180-90-112.5 kg/hm2、F3:120-60-75 kg/hm2)。结果表明,滴灌施肥(W1F1)比CK处理的干物质量、产量和肥料偏生产力(PFP,partial factor productivity of fertilizer)分别增加60.0%、46.9%和47.0%,氮、磷和钾吸收量是CK的1.82~2.41、1.56~2.03和1.36~1.90倍。滴灌施肥下,W1F2干物质量最大(9 258.3 kg/hm2),W1和W2较W3增产19.0%和6.5%,F1和F2较F3增产18.3%和12.9%。生育期内,植株氮、磷和钾吸收量均随灌水量和施肥量的增加而增大(第二果膨大期,F2处理磷和钾吸收量最大除外),灌水量越大,养分利用效率(NUE,nutrient use efficiency)越小,吸收效率(UPE,nutrient uptake efficiency)和PFP越大,施肥量越大,NUE、UPE及PFP均减小。综合分析,滴灌施肥增产效果明显,W1F2(100%ET0,N-P2O5-K2O为180-90-112.5 kg/hm2)处理干物质量最大,有较大的增产潜力,UPE和PFP较高,是适宜的灌水施肥组合。     

Nitrogen fertilization,irrigation, and harvest times affect biomass and energy value of Helianthus tuberosus L.

This study aimed to determine the effects of delayed harvest, irrigation and nitrogen fertilization on yield and fuel quality of the Jerusalem artichoke (JA) (Helianthus tuberosus L.). The biomass, calorific value, ash content and total calories per hectare of the Jerusalem artichoke were assessed in Inner Mongolia, China, at various harvest times, after irrigation and nitrogen application. The results showed that fresh and dry weights of tubers and underground biomass were higher when harvested after freezing; the dry yields of leaves and stems decreased with harvest time. In addition, irrigation significantly enhanced the yields of underground biomass, aboveground biomass and tubers, compared with non-irrigation conditions (p < 0.05). Interestingly, the highest yield was obtained with irrigation and treatment with nitrogenous fertilizers (20 to 50 kg ha^?1). The calorific values of tubers and roots were significantly higher for samples harvested after freezing (p < 0.05); the calorific values of leaves and stems significantly decreased with harvest time and without irrigation (p < 0.05). The calorific values of stems and leaves were higher than those of tubers and roots, when JA was harvested before freezing, and the opposite trend was obtained for harvest done after freezing. The highest calories per hectare was obtained in WN2 (585247.42 MJ ha^?1) on 30 September 2010 harvest. No correlation was found between the effects of water or nitrogenous fertilizers and ash content. However, the ash contents of stems, leafs, tubers and roots were significantly decreased (p < 0.05) with harvest time. Finally, in all treatment conditions, leaves produced the highest ash amounts among all plant parts, including stems, tubers, leaves and roots.     

节水灌溉减施磷肥对黑土稻作产量及土壤磷利用与平衡的影响

为探寻节水灌溉减施磷肥对黑土稻作磷利用及土壤磷平衡的影响,于2020年和2021年开展大田试验,以常规淹灌+常规施磷肥(CK,45 kg/hm2)作对照,节水灌溉模式下设置5个磷肥施用梯度:0(CP0,不施磷肥)、18 kg/hm2(CP1,减磷60％)、27 kg/hm2(CP2,减磷40％)、36 kg/hm2(C...