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1.
ABSTRACT

The effectiveness of nitrogen (N)+ zinc (Zn) soil and foliar fertilizer applications on growth, yield, and quality of apple (Malus domestic Borkh ‘Golden Delicious’) fruit was studied in the Zanjan province, Iran. There were eight treatments 1) control (no fertilizer), 2) soil applied N, 3) soil applied Zn, 4) soil applied N+Zn, 5) foliar applied N, 6) foliar applied Zn, 7) foliar applied N+Zn and 8) combined soil and foliar applied N+Zn. The N source was urea [CO(NH2)2, 46% N] applied at 276 N tree? 1 yr?1 and the Zn source was zinc sulfate (ZnSO4,7H20, 23% Zn) applied at 110 g Zn tree? 1 yr? 1. The soil treatments of N and Zn, were applied every two weeks during June through August (total of 6 times/year) in a 1 m radius around the tree trunk (drip line of trees). The foliar solutions of N (10 g l? 1 urea) and Zn [8 g l? 1 zinc sulfate (ZnSO4)] were sprayed at the rate of 10 L tree? 1 every two weeks at the same times as described for soil applications. The highest yield (49 kg tree? 1), and the heaviest fruits (202 g) were obtained in the soil and foliar combination of N+Zn treatment. The lowest yield (35 kg tree? 1), and the smallest fruits (175 g) were recorded in the control. Nitrogen, and to a lesser extent Zn, foliar application resulted in decreasing fruit quality (caused russeting, and lower soluble solid), but increasing N leaf and fruit concentrations (2.4% DW and 563 mg kg? 1, respectively). There were significant differences among yield and leaf mineral nutrient concentration in different treatments. But there was no significant difference between fruit mineral nutrient concentration (except N). Ratio of N/calcium (Ca), potassium (K)/Ca, and [magnesium (Mg)+K]/Ca in fruits were found suitable for fruit quality prediction. Combining the zinc sulfate with urea in the foliar applications increased the concentration of Zn from 0.7 to 1.5 mg per kg of apple tissue. Leaf N concentration varied during growth season. Foliar applied nutrient can be more efficient than soil applied, but a combination of soil and foliar applications is recommended for apple tree nutrient management.  相似文献   

2.
施用改良剂对山地土壤pH和烤烟生长及产质量的效应   总被引:2,自引:0,他引:2  
为明确酸性土壤改良剂施用方法,采用三因素二水平的大田试验,研究改良剂种类、施用时间和施用量对植烟土壤pH的影响及对烤烟农艺性状、经济性状和烟叶物理特性、化学成分的效应。结果表明,与对照(CK)相比,施用改良剂能显著提高土壤pH值(移栽后60 d可提高1.24~1.58;移栽后120 d可提高0.39~0.54);施用低剂量石灰有利于打顶前烤烟株高和茎围的生长,施用酸性土壤调理剂有利于打顶前烤烟叶片的生长;施用改良剂主要影响烤烟经济性状指数(ECI)、烟叶物理特性指数(PPI)、烟叶总氮含量,以改良剂用量对烤烟经济性状影响最大,改良剂种类和施用时间互作对烟叶物理性状影响最大,改良剂用量对化学成分影响最大;与CK相比,施用改良剂其烤烟上等烟比例提高7.32~15.46个百分点,均价、产量、产值分别提高1.22%~9.81%、1.72%~40.65%、2.74%~42.67%,其烤烟ECI、烟叶PPI、烟叶CUUI分别提高6.53%~32.31%、0.65%~7.04%、0.36%~13.87%。生产上应用改良剂的方法为,在烤烟整地时施用1 500 kg·hm-2石灰的...  相似文献   

3.
Barley (Hordeum vulgare L.) is a cereal grown for animal feed, human consumption, and malting. Nutrient concentrations are important as they provide information regarding the dietary values of barley consumed by animals or human beings. In addition, grain nutrient removal may be useful for refining fertilizer recommendations. A study was conducted in 2015 and 2016 investigating the cultivar effects on grain yield, quality, and grain nutrient concentrations and removal under irrigated conditions for two-row barley cultivars. Adjunct and feed cultivars produced the highest yields compared with the all-malt and food cultivars. Specific quality and nutrient values were greater than or equal to in the food cultivar compared to the malt or feed cultivars. Variations in nutrient concentrations were measured among the adjunct and all-malt cultivars, which could potentially affect the malting and brewing qualities. Grain yield, quality, nutrient concentrations and nutrient removal varied among cultivars grown under identical environmental conditions, which may influence end-use.  相似文献   

4.
营养缺乏和水分胁迫各自对春小麦的生长发育和产量形成有直接影响.分析了春小麦的植株水分状况、生育期、叶片生长、干物质积累和产量构成等在受到水分胁迫下的变化后,认为在一定水分胁迫条件下增加无机营养,能促使春小麦绝对产量显著增加;生活在营养缺乏条件下的春小麦则能产生一系列适应于干旱环境的性状,遇到水分胁迫时受到的影响相对较小(营养充足条件下水分胁迫使产量下降的比率大于营养缺乏条件下的比率).据此如何掌握各种不同程度干旱下的施肥技术,既能使作物维持必需的生长量,同时又能抵御一定程度的水分胁迫,是一个值得进一步研究  相似文献   

5.
Dry bean is an important legume and nitrogen (N) deficiency is one of the most yield-limiting factors in most of the bean-growing regions. A greenhouse experiment was conducted with the objective to determine influence of N on growth, yield, and yield components and N uptake and use efficiency of 23 dry bean genotypes. Straw yield, grain yield, yield components, maximum root length, and root dry weight were significantly increased with the addition of N but varied with genotypes. The N × genotype interactions were also significant for most of these traits, indicating variation in responses of genotypes with the variation in N levels. There was significant difference in N uptake and use efficiency among genotypes. Most of growth and yield components were significantly and positively associated with grain yield. Based on grain yield efficiency index (GYEI), genotypes were classified into efficient, moderately efficient, or inefficient group in N-use efficiency. Nitrogen concentration was greater in grain compared to straw, indicating greater N requirement of dry bean genotypes.  相似文献   

6.
为了探索启动磷肥不同施用方式对玉米生长和产量的影响,设置启动磷肥大田滴施(T1)、穴施(T2)和不施启动磷肥(CK)3个施肥处理,其中启动肥磷肥用量为P2O5 30 kg·hm-2,探究启动磷肥不同施用方式对玉米生长、养分分配和产量构成的影响;设置启动磷肥根箱土壤滴施(P1)、穴施(P2)和不施启动肥(CF)3个处理,其中启动肥磷肥用量为P2O5 0.2 g·kg-1土,探究启动磷肥施用后土壤中磷素的空间分布与迁移效果。结果表明,玉米四叶期和六叶期,T1和T2处理均显著增加了苗期玉米总根长,根表面积,地上、地下部生物量和N、P、K养分积累量。在六叶期,T1和T2处理玉米总根长较CK分别增加了21.10%和30.35%,根系表面积分别增加了23.48%和29.20%,地上和地下部生物量分别增加了31.24%和52.38%、33.61%和57.81%。与CK相比,T1和T2处理促进了玉米N、P、K养分的积累,同时促进了养分由营养器官向生殖器官的转移。在玉米吐丝期至成熟期,T1和T2处理玉米N、P、K养分转移量较CK分别增加了29.75和44.73 kg·hm-2、10.76和14.65 kg·hm-2、2.20和24.67 kg·hm-2。玉米穗长、行粒数、产量和磷肥偏生产力均表现为T2>T1>CK,玉米穗秃尖长度表现为T2相似文献   

7.
采用田间试验研究了内蒙古巴彦淖尔市河套灌区甜瓜一次性施肥、覆膜后灌水淋洗排盐传统种植模式下不同施肥对土壤养分及甜瓜产量、品质和养分利用的效应,不同施肥处理包括不施肥(CK)、常规施肥(CF,N 445.5 kg/hm2,P2 O5399 kg/hm2,K2 O 54 kg/hm2)、优化减量施肥(RF,N 240 kg...  相似文献   

8.
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。  相似文献   

9.
ABSTRACT

Field experiments were carried out for three consecutive years (2003–2006) at Bangladesh Sugarcane Research Institute farm soil on plant (first crop after planting) and subsequent two ratoon crops of sugarcane. The main objectives of the study were to assess the direct and residual effects of organic and inorganic fertilizer on growth, yield, and juice quality of plant and ratoon crops. The plant crop consisted of four treatments. After harvesting of plant crop to evaluate the residual effects on ratoon crop the plots were subdivided except the control plot. Thus, there were seven treatments in the ratoon crop. Application of recommended fertilizer [nitrogen (N150), phosphorus (P52), potassium (K90), sulfur (S35), and zinc (Zn3) kg ha? 1] singly or 25% less of it either with press mud or farmyard manure (FYM) at 15 t ha? 1 produced statistically identical yield ranged from 67.5 to 69.0 t ha? 1 in plant crop. In the ratoon experiment when the recommended fertilizer was applied alone or 25% less of its either with press mud or FYM at 15 or even 7.5 t ha? 1 again produced better yield; it ranged from 64.8 to 69.2 in first ratoon and 68.2 to 76.5 t ha? 1 in second ratoon crops. Results showed that N, P, K, and S content in leaf progressively decreased in ratoon crops over plant crop. Juice quality parameters viz. brix, pol, and purity % remained unchanged both in plant and ratoon crops. Furthermore, organic carbon (C), available N, P, K, and S were higher in post harvest soils that received inorganic fertilizer in combination with organic manure than control and inorganic fertilizer treated soil. It may be concluded that the application of 25% less of recommended fertilizer (N112, P40, K68, S26, and Zn2.2.5 kg ha? 1) either with press mud or FYM at 15 t ha? 1 was adequate for optimum yield of plant crop. Results also suggest that additional N (50% extra dosage) keeping all other fertilizers at the same level like plant crop i.e. N168, P40, K68, S26, and Zn2.25 kg ha? 1 either with press mud or FYM at 7.5 t ha? 1 may be recommended for subsequent ratoon crops to obtain good yield without deterioration in soil fertility.  相似文献   

10.
不同施氮量对高粱产量及植株养分积累的影响   总被引:4,自引:0,他引:4  
利用控制性的大田试验栽培技术,连续2a采用氮的添加试验,研究了不同施氮量(CK、低氮LN、中氮MN、高氮HN)对高粱(Sorghum bicolor)产量及植株养分积累的影响。结果表明:施氮处理下高粱植株株高、根长、叶面积指数、茎粗、地上和地下生物量均高于对照,随着氮浓度的增加,高粱植株生长各指标以中水平施氮(MN)处理下达到最大,说明施氮能够促进高粱的生长,但氮肥在高用量时可能会产生轻微抑制作用;施氮对高粱植株叶绿素、可溶性蛋白和可溶性糖含量均有明显的促进作用,不同施氮处理下高粱叶绿素a和b、可溶性糖和可溶性蛋白含量呈先增加后减小的趋势,说明施氮能够促进高粱叶片叶绿素合成;高粱植株不同部位的碳、氮、磷和钾积累量表现出较大的差异,穗部的碳、氮、磷和钾积累量最高,其次是叶片,根部碳、氮、磷和钾积累量最低,其中不同部位的碳、氮、磷和钾积累量均表现为MNHNLNCK,由此表明了施氮能够增加高粱碳、氮、磷和钾的积累量;施氮对高粱植株养分的影响表现为一定程度的增加效应,随施氮量的增加高粱植株养分呈先增加后降低的趋势,表明了高粱植株在一定程度上对养分的累积作用,其增幅随施氮量的增加而增加。Pearson相关性分析表明,施氮量与株高、茎粗、单株叶面积、单株干重、籽粒产量、穗数和千粒重呈现出显著性相关关系,由此表明,施氮量与高粱主要性状以及养分吸收息息相关,在高粱高产高效栽培中起着重要的作用。  相似文献   

11.
针对设施菜地施肥量大、肥料利用率低、果实品质变差、土壤环境劣质等问题,采用田间试验法,研究了无机肥配施不同土壤调理措施对设施黄瓜产量、品质、养分利用及土壤改良的影响,为实现蔬菜安全生产和保护土壤环境质量提供科学依据。结果表明:与农民习惯施肥相比,推荐无机肥配施生物菌肥、中微量养分、沸石处理的氮磷钾无机肥用量均减少40%左右,黄瓜产量却提高6.3%~8.7%,纯收入增加18 663~19 958元/hm2,其中推荐无机肥配施生物菌肥的整株植物氮、钾积累量分别增加13.3%和22.7%,土壤细菌、放线菌数量和细菌/真菌比值分别增加3.2,1.7,7.7倍;推荐无机肥配施沸石的整株磷积累量增加31.7%,表层土壤NH4+—N提升31.6%;配施生物菌肥和中微量养分处理的VC、可溶性蛋白和可溶性糖含量分别增加14.0%~18.6%,22.2%~34.6%,7.8%~10.0%,硝酸盐降低15.8%~21.7%。与推荐施肥比较,3种土壤调理措施氮磷钾肥生产效率提高6.2%~8.5%,氮磷钾肥农学效率增加26.1%~35.9%。说明3种土壤调理剂均促进黄瓜养分吸收,增加产量,改善其果实品质,降低土壤氮素残留,增加土壤有益微生物数量,其中以推荐无机肥配施生物菌肥既稳产提质,生物和土壤环境效益又较佳,值得在生产中推荐应用。  相似文献   

12.
氮素形态对小麦生长中后期保护酶等生理特性的影响   总被引:26,自引:2,他引:26  
在水培条件下,探究了氮素形态对小麦营养生殖并进生长时期保护酶的影响。结果表明:铵、硝态氮单供和混合供应对小麦保护酶活性影响不同。在铵、硝态氮混合供应下,叶片SOD、CAT,根系SOD活性最高,同时叶片、根系可溶性蛋白含量最大,根系活力和根系表面K3Fe(CN)6还原活性最高,但MDA含量最高;单供硝态氮时叶片POD活性最高,根系MDA含量最高;单供铵态氮时根系POD、CAT活性最高。单供尿素时叶片仅CAT活性高于铵和硝态氮混合供给,但同时叶片MDA含量也高于铵和硝态氮混合供给。叶片以SOD、CAT和POD为主清除自由基,而根系以SOD和POD为主清除自由基。铵和硝态氮混合供给下,小麦成熟后,地上部干重,籽粒产量最大,根冠比最小。  相似文献   

13.
利用基质栽培水肥一体化技术,设计不同钙素营养供给水平(0,1,3,6 mmol/L),研究钙对无限生长型番茄钙吸收利用及果实品质和产量的影响。结果表明:钙在番茄植物各部位中的分布极不均匀,且同一部位不同时期钙含量差异也很大,植物体内钙的分布和变化受钙素营养水平和气温的影响;随着钙水平的提高,番茄果实钙含量不断增加,缺钙将降低果实的产量和品质,虽然钙与K、Mg、P、N元素之间存在拮抗作用,但是高钙不会造成果实产量和品质的下降;高温会诱导植株缺钙症状及果实脐腐病的出现,严重影响番茄的产量和品质,高钙处理对高温胁迫具有一定的缓解作用。  相似文献   

14.
不同浓度钙营养液对烟草矿质营养吸收与积累的影响   总被引:9,自引:1,他引:9  
本文采用温室水培的方法,研究了不同的钙素供应水平对烟草各种矿质养分的吸收与积累的影响。结果表明,在其它养分形态与浓度一致条件下,随着钙浓度从75mgL-1提高到900mgL-1,烟草生长量呈抛物线型变化。钙浓度为150mgL-1时烟株干物质量最大。超过150mgL-1,随钙的增加而下降,当钙素达900mgL-1(K/Ca为1/6)时,烟株生长严重受抑。随着供钙水平由低到高,烟株氮、磷、钾、锌、锰含量均呈抛物线型变化,含钙量呈直线上升关系,而镁和铜含量则随钙浓度提高而显著下降。烟株各养分积累量均随营养液钙浓度提高呈抛物线型变化,但不同养分出现最大积累量时的营养液钙浓度却不相同。不同供钙水平上烟叶中各元素含量的变化特征与全株的结果基本一致。在低钙浓度范围(75~300mgL-1),钙对钾有协合关系,增钙促进提钾,大于300mgL-1后有拮抗作用,提钙导致降钾。钙与镁、锌、铜、锰间也存在明显的交互作用。烟叶中各元素含量与积累量的变化趋势与整株基本一致。  相似文献   

15.
养分合理调控对西兰花生长、品质及土壤特性的影响   总被引:2,自引:0,他引:2  
为避免不合理施肥及连作导致的西兰花产量低、品质差等问题,采用田间试验方法,设置农民习惯施肥(CK)、合理减量无机肥(MF)、合理减量无机肥配施生物肥(BF1、BF2)4个处理,研究了合理减量无机肥及配施生物肥对西兰花生长、产量、品质、养分吸收和土壤性状的影响。结果表明:每形成1 000kg西兰花花球,平均需要吸收N、P2O5、K2O分别为1.37kg,0.61kg,0.92kg。与CK相比,MF、BF1和BF2的花球单重和直径分别平均增加12.76%,12.11%;增产10.90%~14.16%;可溶糖含量平均提高10.40%,Vc含量平均增加22.83%;N、P2O5、K2O吸收量分别平均提高7.00%,26.83%和8.93%,地上部养分总吸收量平均提高11.32%;各处理土壤养分含量和微生物数量均有不同程度的变化,但差异不显著。与MF相比,BF1和BF2处理的蛋白质含量平均提高17.14%。合理减量无机肥及配施生物肥能促进西兰花生长,增强茎、叶、花球性状,促进同化产物的合成及其由茎叶向花球中的转移,促进养分吸收,提高产量;同时改善品质,提高可溶性糖和Vc含量,配施生物肥能提高蛋白质含量;对土壤养分含量和微生物数量无显著影响,但是由于其减少了氮肥用量,提高了西兰花氮素吸收量,降低了土壤中氮素残留过多污染环境的风险。综合考虑西兰花的生物学性状、养分吸收利用、产量、品质和土壤性状及实际生产需求等,以合理减量无机肥配施丰满屯生物肥效果最好。  相似文献   

16.
This study evaluated the petiole uptake of nitrogen, phosphorus, potassium, and sulfur (N, P, K, and S) by the potato from two seed meals, mint compost, and five commercially available organic fertilizers under an irrigated certified organic production system. Available soil nitrate (NO3-N) and ammonium (NH4-N) from each amendment averaged 115 kg N ha?1 at application and 25 kg N ha?1 30 d after planting through harvest, with minor differences between fertilizers. Petiole N declined from an average of 25,000 mg N kg?1, 4 wk after emergence to 3,000 mg N kg?1 prior to harvest. Petiole P and K concentrations were maintained above 4,000 mg P kg?1, 10,000 mg K kg?1, and 2,000 mg S kg?1 tissue, respectively, throughout the growing season in all treatments. Tuber yields were not different between fertilized treatments averaging 53 Mg ha?1. This study provides organic potato growers baseline information on the performance of a diverse array of organic fertilizers and amendments.  相似文献   

17.
A field experiment was conducted to study the effect of silicon (diatomaceous earth, DE) fertilization on growth, yield, and nutrient uptake of rice during the kharif season of 2012 and 2013 in the new alluvial zone of West Bengal, India. Results showed that application of silicon significantly increased grain and straw yield as well as yield-attributing parameters such as plant height (cm), number of tillers m?2, number of panicle m?2, and 1000-grain weight (g) of rice. The greatest grain and straw yields were observed in the treatment T6 (DE at 600 kg ha?1 in combination with standard fertilizer practice (SFP). The concentration and uptake of silicon, nitrogen (N), phosphorus (P), and potassium (K) in grain and straw were also greater under this treatment compared to others. It was concluded that application of DE at 600 kg ha?1 along with SFP resulted increased grain, straw, and uptake of NPK.  相似文献   

18.
The purpose of the present work was to evaluate effects of zinc application on growth and uptake and distribution of mineral nutrients under salinity stress [0, 33, 66, and 99 mM sodium chloride (NaCl)] in soybean plants. Results showed that, salinity levels caused a significant decrease in shoot dry and fresh weight in non-zinc application plants. Whereas, zinc application on plants exposed to salinity stress improved the shoot dry and fresh weight. Potassium (K) concentration, K/sodium (Na) and calcium (Ca)/Na ratios significantly decreased, while sodium (Na) concentration increased in root, shoot, and seed as soil salinity increased. Phosphorus (P) concentration significantly decreased in shoot under salinity stress. Moreover, calcium (Ca) significantly decreased in root, but increased in seed with increased salinization. Iron (Fe) concentration significantly decreased in all organs of plant (root, shoot, and seed) in response to salinity levels. Zinc (Zn) concentration of plant was not significantly affected by salinity stress. Copper (Cu) concentration significantly decreased by salinity in root. Nonetheless, manganese (Mn) concentration of root, shoot, and seed was not affected by experimental treatments. Zinc application increased Ca/Na (shoot and seed) ratio and K (shoot and seed), P (shoot), Ca (root and seed), Zn (root, shoot, and seed) and Fe (root and shoot) concentration in soybean plants under salinity stress. Zinc application decreased Na concentration in shoot tissue.  相似文献   

19.
The effects of nutrient or sodium chloride (NaCl) salinity on pepper grown in closed soilless culture systems were studied. A control (2 dS m?1) and two saline nutrient solutions (4 dS m?1) differing in the salt sources (fertilizers or NaCl) were studied. Shoot biomass production as well as total and marketable yield were more affected by NaCl than nutrient salinity. Fruit dry matter and total soluble solids increased in both salinity treatments compared to the control. Total phenol content rose slightly (10%) with NaCl salinity, while the concentration of carotenoids was enhanced by 40% with NaCl compared to the control and nutrient salinity. The results showed that the response of pepper to salinity is both osmotic and ion specific, but a more negative effect was recorded under NaCl stress. Moreover, the highest content of antioxidant compounds in NaCl treated fruits may indicate that NaCl caused more stressful conditions than nutrient salinity.  相似文献   

20.
《土壤通报》2014,(5):1195-1201
分别于2009和2010年,通过田间小区试验进行了滴灌施肥对玉米生长发育、养分吸收及产量的影响。结果表明:2009年玉米干物质累积最快的时期是在播种后59~99 d,OPT处理(根据土壤测试值而确定的施肥量)的干物质积累速率的最大时刻t0比其它处理提前了5~6 d。处理间的N吸收量、P2O5吸收量和K2O吸收量都达到了显著差异水平;氮肥、磷肥和钾肥的利用率分别为45.69%、24.89%和40.11%。玉米各处理间的产量都达到了极显著差异水平,OPT-N(不施氮)、OPT-P(不施磷)、OPT-K(不施钾)和CK(不施肥)处理的产量分别相当于OPT处理的68.48%、89.49%、94.95%和63.85%;氮肥、磷肥和钾肥对玉米产量的贡献率分别是31.52%、10.51%和5.05%。2010年处理间的N吸收量、P2O5吸收量和K2O吸收量也都达到了显著差异水平;氮肥、磷肥和钾肥的利用率分别为45.46%、28.01%和46.96%。玉米各处理的产量间都达到了极显著差异水平,OPT-N、OPT-P和OPT-K处理的产量分别相当于OPT处理的69.03%、80.94%和84.99%;氮肥、磷肥和钾肥对玉米产量的贡献率分别是30.97%、19.06%和15.01%。综合产量和养分积累方面的研究结果,两年的试验都表明氮肥是玉米产量的主要限制因子,其次为磷肥和钾肥。  相似文献   

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