马铃薯氮素的吸收、积累和分配规律

植株体内氮素浓度的高低反映了其生长势的强弱,马铃薯生育期间各器官氮素浓度的变化始终表现为叶片>地上茎>块茎,叶片中的氮素浓度高低反映了叶片光合活性的大小。马铃薯对氮的吸收与营养生长和块茎的增长密切相关,植株对氮的需求量受其生长状况所控制。而且,氮在植物体内很容易流动,块茎形成后,大量的氮素转移到块茎中,用于块茎的建成和营养贮存。马铃薯植株在淀粉积累开始后,各器官中氮素加快了向块茎的转移,使叶片和地上茎的衰老进一步加剧。因此,在马铃薯高产栽培实践中,须注重氮、磷、钾的适量与配合施用,使之既能满足块茎的形成与生长的需要,又可防止植株生长过旺或后期发生早衰。本试验表明,在因素中量(适量)组合下,每生产500kg块茎需要纯N2 65kg。     

不同施肥处理对水稻产量和效益的影响

通过田间试验研究不同施肥处理对水稻产量、品质和经济效益的影响,从而确定水稻最佳施肥组合及产量限制因子。结果表明:限制该地产量的因子主要在氮和磷,N∶P2O5∶K2O=21∶7.4∶10.5的最佳施肥组合为合理施肥量,但不是最佳量,此结果还有待进一步试验验证。     

Interrelations between nitrogen and phosphorus fertilization and early blight control of potatoes

Three different rates of soil-applied nitrogen were combined in all possible combinations with different schedules of fungicidal sprays for early blight (Alternaria solani) control in field experiments for three consecutive years. The nitrogen was applied with a constant rate of phosphorus. Yield response to fungicidal sprays was more pronounced when potato plants had received nitrogen and phosphorus. Both spraying and fertilizer application reduced the percentage of leaflets infected by early blight. However, the effect of the fungicide was greater than that of fertilizers. Estimates based on the cost and price assumptions indicated that $1.00 investment in the optimum number of fungicidal sprays at the adequate rate of fertilizer returned $8.34, $9.71 and $1.89 in 1970, 1971 and 1972, respectively.     

不同施肥水平下青蒿氮、磷、钾养分吸收特性

通过大田试验研究不同施肥水平下青蒿氮、磷、钾的吸收、累积与分配规律。选用当地主栽青蒿品种渝青 1 号为材料,设置高肥、中肥和低肥 3 个施肥水平。于苗期、分枝初期、分枝盛期及蕾期采集植株样本,分为根、茎、 枝和叶 4 部分,测定氮、磷、钾含量,计算青蒿主要生育期植株养分吸收、累积和分配情况。结果表明：青蒿对钾肥 的需求量最多,氮肥次之,磷肥最少。高肥和中肥处理整个生育期氮在不同器官中的含量为叶>枝>根>茎。低肥处理整 个生育期氮在不同器官中的含量为叶>枝>茎>根。高肥、中肥和低肥 3 个处理整个生育期磷在不同器官中的含量均为叶 >枝>茎>根。苗期和蕾期生长阶段高肥、中肥和低肥 3 个处理钾在不同器官中的含量均为叶>枝>茎>根,分枝初期和分 枝盛期生长阶段 3 个施肥处理钾在不同器官中的含量均为枝>叶>茎>根。不同施肥处理对养分积累趋势影响不大,但可 显著影响各器官在不同生育时期的养分积累量及分配比例。养分累积吸收量在生育前期较少,生育中后期急剧增加。 养分累积量以钾最多,氮次之,磷最少。青蒿中氮磷钾的吸收、累积与分配规律在不同施肥水平下存在差异,生产中 应根据土壤肥力和产量目标,采取合理施肥措施,达到经济施肥的目的。     

马铃薯对氮、磷、钾的吸收及分配规律研究进展

马铃薯的生长发育受到很多因素的影响,特别是养分的供应以及马铃薯对养分的吸收、利用,对其块茎的形成、膨大及淀粉积累的影响尤为显著。氮、磷、钾在马铃薯生长发育中需要量大,必须加以补充,才能满足其正常生长需求。生产上不合理的施肥,导致马铃薯产量不高、品质较差及生产成本增高。通过分析马铃薯不同生育阶段、不同器官吸收养分的特征和分配规律,从而探索马铃薯生产中最佳的氮、磷、钾施肥组合,这对于丰富马铃薯栽培生理理论和指导生产中氮、磷、钾肥合理配施均具有重要的现实意义。     

陕西关中不同小麦品种产量以及氮磷效率差异研究

为筛选出高产高效的小麦品种,以陕西关中平原现行栽培以及新育成的15个主要小麦品种为材料,通过大田试验,在两个施肥处理下(不施肥,推荐施肥),研究不同小麦品种的产量、氮磷效率差异及其内在生理机制.结果 表明,在施肥和不施肥条件下,部分小麦品种间的产量均存在显著差异,其中,施肥条件下小麦产量为2 757.5～4 589.5...     

玉米高产与氮肥高效协同实现存在的问题及其途径

综述施氮对玉米产量、品质及氮素利用率的影响。随施氮量增加,玉米产量先升高后降低,在150~180 kg/hm2可达到最大值;适量施氮可以改善玉米子粒品质;氮肥利用率和氮肥偏生产力均随施氮量增加而降低。通过多年多点数据分析得出,我国华北地区玉米的适宜施氮量为180 kg/hm2左右,可实现玉米高产高效。通过合理减少氮肥用量、改进施肥技术、应用新型肥料并将氮肥运筹与综合农艺管理相结合,可以实现玉米产量和氮素利用效率的协同提高。     

Economic Optimum Nitrogen Fertilization Rates and Nitrogen Fertilization Rate Effects on Tuber Characteristics of Potato Cultivars

The objective of the research was to determine the economic optimum nitrogen (N) fertilization rates and to determine the effects of N fertilization rates on tuber characteristics and fresh mass loss after storage under cold and ambient conditions of four potato cultivars, Ágata, Asterix, Atlantic, and Monalisa. The experiments were, simultaneously, conducted in the same area and similar experimental conditions during the fall/winter period in Viçosa, Minas Gerais State, Brazil. In each experiment, five N fertilization rates (0, 50, 100, 200, 300 kg ha^?1) were evaluated in a randomized complete block design. For all cultivars, increasing N fertilization rate increased total and marketable yields and tuber dry matter yield up to a maximum following a quadratic model. Increasing N fertilization rate linearly increased the tuber protein concentration of Atlantic and Monalisa and had no effect on tuber pH. N fertilization rate effects on tuber mass, tuber titratable acidity, and fresh mass loss during storage were cultivar-dependent. N use efficiency (tuber yield divided by N fertilization rate) decreased with increase in N fertilization rate. The economic optimum N fertilization rates ranged from 147 to 201 kg ha^?1 depending upon cultivar and relative prices of N and potato tubers. Depending on the cultivar, under favorable price conditions (low N price and high tuber price), the economic optimum N fertilization rates to be applied by potato growers were 92–95% of the estimated N fertilization rate for obtaining the maximum potato yield, whereas under unfavorable conditions (high N price and low potato tuber price) the economic optimum N fertilization rates to be applied should be decreased to 86–92% of the rates for maximum yield.     

Management of nitrogen and phosphorus rates does not suppress verticillium wilt in yukon gold

Effect of nitrogen and phosphorus fertilization rates on the incidence of Verticillium wilt caused byVerticillium albo-atrum orV. dahliae and tuber yield in potato cv Yukon Gold was evaluated in field plots. In three years of study,V. albo-atrum caused a higher incidence of wilt symptoms (74%–100%) thanV. dahliae (5%–81%) resulting in lower marketable tuber yield. In plots infested withV. albo-atrum, tuber yield ranged from 12.3-22.8 T ha1 compared to 18.1– 31.5 T ha^-1 in plots infested withV. dahliae. Application of nitrogen above (280 kg ha^-1) or below (70 kg ha^-1) the recommended rate of 140 kg ha^-1 at planting did not suppress foliar symptoms or protect against yield loss caused by eitherV. albo-atrum orV. dahliae. Similarly, phosphorus rate adjustments did not consistently affect disease incidence regardless of the pathogen. Management of nitrogen or phosphorus fertility rates at planting does not appear to be a viable approach for suppressing Verticillium wilt in the determinant, wiltsusceptible cultivar Yukon Gold.     

Effect of nitrogen fertilization on Fusarium head blight in spring barley

Nitrogen fertilization has been shown to influence the occurrence and the impact of Fusarium head blight in wheat. It also plays a key role in adjusting barley quality to the requirements of the malting industry, implying specific contents of protein. The present study investigated the effect of nitrogen input on the incidence of relevant Fusarium species in spring barley under field and greenhouse conditions. Grain material from differently fertilized field plots was analyzed for fungal DNA and mycotoxins by qPCR and LC-MS/MS, respectively. Under natural pathogen pressure no effect of nitrogen on infection was observed. When pathogen pressure (Fusarium culmorum and Fusarium avenaceum) was increased via species-specific soil-surface inoculation, nitrogen application reduced contents of Fusarium DNA and mycotoxins in barley grain. Nitrogen-dependent canopy parameters were recorded over the season and correlated with DNA and mycotoxin data. Apparently, sparser canopy permitted more Fusarium infections in unfertilized plots. In addition, well nitrogen-fertilized plants allowed less fungal development in the barley spike after spray inoculation in the greenhouse. These results suggest that nitrogen fertilization restricts Fusarium grain infection of barley by influencing canopy characteristics and possibly plant physiology.     

不同氮、磷、钾水平对水稻纹枯病的影响

田间试验研究了不同氮、磷、钾水平对水稻纹枯病发生程度和产量的影响。结果表明,水稻纹枯病的发病率与N、P、K关系分别为:随氮肥施入量的增加,呈先缓慢上升,再大幅度上升的趋势;随磷肥施入量的增加,呈先小幅度上升,再大幅度下降,然后再大幅度上升的趋势;随钾肥施入量的增加,呈现大幅度下降,再大幅度上升的趋势。产量结果表明:不同氮、钾处理对水稻产量影响大,不同磷处理对水稻产量影响小。适用于寒地的施氮量97kg/hm2、施磷量52kg/hm2、施钾量29kg/hm2,使纹枯病发病轻,提高水稻产量。     

氮磷钾优化施肥对夏大豆产量的影响

氮磷钾优化施肥试验研究表明:夏大豆籽粒产量和单株粒数与氮磷钾施肥量呈二次曲线关系,籽粒产量和单株粒数随着施肥量的增加而增加,增加到一定水平后又开始下降。大豆籽粒产量和单株粒数受施氮量的影响最大,磷肥次之,钾肥更次之。在土壤供肥能力1 568.6 kg/hm2,密度为18万株/hm2的条件下,当施氮量为65.56 kg/hm2,施磷量63.73kg/hm2,施钾量39.25 kg/hm2时,濉科998产量最高,最高产量为2 745.7 kg/hm2;当施氮量为64.80 kg/hm2,施磷量59.42kg/hm2,施钾量37.11 kg/hm2时施肥效益最高,经济产量为2 743.7 kg/hm2。     

扬麦12肥料试验初报

【目的】为氮、磷、钾肥在小麦生产中的科学施用提供理论与技术依据。【方法】以扬麦12为供试品种．采用“3414”最优回归设计研究不同施肥方案对小麦经济性状和产量的影响,并通过拟合三元二次和一元二次肥效模型,确定小麦的最佳推荐施肥量。【结果】施氮、磷、钾肥小麦的增产率分别为306．50％、8．49％和4．24％;不施氮、磷、钾肥小麦的相对产量为24．60％、92．17％和95．93％、土壤地力贡献率为21．82％,萧山区土壤氮、磷、钾的丰缺等级分别为极低、中、高。[结论]在该试验条件下,施氮效果最好,磷肥次之,钾肥有一定增产增收效果;结合当地生产实际,确定氯、磷、钾肥最佳经济推荐施用量分别为266．40、73．20、53．70kg／hm2。     

Fertilizer and planting strategies to increase biomass and improve root morphology in the natural rubber producer Taraxacum brevicorniculatum

Taraxacum brevicorniculatum produces high-quality natural rubber in its roots and could be developed as an alternative commercial source of this valuable raw material. However, current wild type accessions have a low biomass and branched roots that make them difficult to harvest. We set out to determine the optimum fertilizer and spacing requirements for T. brevicorniculatum plants in greenhouse and field trials, aiming to increase root biomass and reduce branching thus maximizing rubber yield and reducing losses during harvesting. Our preliminary data from greenhouse trials show that fertilizers containing calcium and magnesium in addition to NPK (nitrogen, phosphorus and potassium) increase root biomass by 25% compared to standard NPK fertilizer plus boron, and by 15% compared to NPK plus calcium. Fertilizers with a low N:P ratio increased the root biomass in greenhouse and field trials. Dense sowing (5-10 cm between plants) inhibits root branching and leads to the formation of single taproots that can be harvested easily. We therefore provisionally recommend the application of low N:P ratio NPK fertilizer supplemented with calcium and magnesium to closely-spaced plants in order to achieve the greatest increase in plant biomass per hectare.     

Could the Supply of Boron and Zinc Improve Resistance of Potato to Early Blight?

The adequate supply of boron (B) and zinc (Zn) can improve the structural integrity and permeability of cell membranes, which is a defence mechanism against fungi infection. A greenhouse experiment was conducted to investigate the effect of the application of B and Zn on plant growth and the incidence and severity of potato early blight, a destructive foliar disease of potato crop caused by Alternaria grandis E.G. Simmons. Potato plants (Solanum tuberosum L. cv. Ágata) were grown in 11-l pots filled with sandy soil, unfertilized or fertilized with 5 mg kg^?1 B and 5 mg kg^?1 Zn (either alone or in combination). Potato plants were inoculated with isolates of Alternaria grandis at 40 days after planting. Early blight incidence and severity were evaluated visually 7 days after inoculation with A. grandis isolates. Disease incidence ranged from 16 to 41% infected leaves, and was significantly highest in the treatment with the application of B, followed by the control, and lowest with application of Zn and B + Zn. Early blight severity ranged from 2.5 to 25%, and was significantly higher in the unfertilized treatment than in those fertilized with Zn either alone or in combination with B. These findings suggest that Zn plays a critical role in potato tolerance to early blight and should be considered as a preventive measure in the disease management plan, since application of zinc reduced the incidence and severity of potato early blight. However, the physiological basis of this remains unknown.     

海南临高辣椒主产区产量差及其限制因子分析

目前有关海南辣椒生产现状的研究极少，探索辣椒主产区产量差，同时分析其限制因子，能够为提高海南辣 椒栽培水平提供理论基础。本研究对海南省临高县 52 个农户螺纹椒产量、施肥和管理情况进行调研，分析辣椒产量与 各因子之间的关系。结果表明：高产组平均产量达 62.64 t/hm2 ，与低产组的产量差为 46.5 t/hm2 。辣椒产量与复合肥投 入基追比呈显著负相关，与复合肥投入量和农药使用次数呈显著正相关。此外，本试验区磷养分的投入过高，造成土 壤磷的过量积累。该调查结果表明，调查区域应推广高氮高钾型复合肥，以减少土壤中磷的过量积累。低产农户提高 复合肥用量和追肥比例，并加强病虫害防治，可提高产量。     

优化施肥对甘蔗产量、养分吸收及肥料利用率的影响

过量施用化肥不仅影响甘蔗的生长发育,而且导致化肥利用率低和污染环境。以甘蔗品种新台糖22号为材料,采用随机区组设计,通过两年（造）田间试验,探讨优化施肥对甘蔗产量效应、养分吸收和肥料利用率的影响。结果表明,优化施肥处理（N 345 kg/hm2,P2O5 195 kg/hm2,K2O 240 kg/hm2）甘蔗平均产量高于常规施肥处理（N 404 kg/hm2,P2O5 296 kg/hm2,K2O 281 kg/hm2）;甘蔗分蘖期和伸长期的氮和磷吸收量显著高于常规施肥处理;氮、磷、钾肥料利用率显著高于常规施肥,分别提高6.1％、5.5％和13.3％。适当减少化肥施用量,调整氮磷钾配比,可促进甘蔗分蘖期和伸长期对氮和磷的吸收,提高肥料利用率和产量。甘蔗优化施肥是一种兼顾经济效益和环境效益的合理施肥方案,值得推广应用。     

我国南方红黄壤地区优质油菜营养特性与施肥效应研究：Ⅰ.不同油菜品种的氮

在亚热带红黄壤地区稻田土壤上,研究５个双低油菜新品种（品系）和２个常规油菜品种在不同施肥条件下的氮、磷养分吸收积累差异及对生物学产量和籽粒产量的影响。结果表明,双低油菜品种中油１１９、中双４号苗期至成熟期的植株氮浓度略低于常规油菜中油８２１,品种间的植株磷浓度差异不显著。苗期中双４号、中油１１９的氮吸收量大于中油８２１和８３１３,花期则反之。生育前期不同品种磷吸收量的差异不显著,成熟期双低品种磷积累量低于常规品种。在ＮＫ基础上增施磷,使油菜植株氮代谢高峰期推迟,氮肥的当季作物利用率提高２０％,植株磷浓度和吸收量在幅度提高,当季作物磷肥的利用率达到３２％。未施磷条件下,中油１１９籽粒产量高于其他常规品种,施磷则表现中油８２１的增产率高于中油１１９、中双４号等双低品种,生物学产量亦表现同样趋势。     

A Knowledge-Based Model for Nitrogen Management in Rice and Wheat

Abstract

Excessive nitrogen fertilization results in low nitrogen-use efficiency. To improve nitrogen management for high yield and high nitrogen efficiency in rice and wheat, we developed a knowledge-based nitrogen fertilization model by integrating the quantitative relationship between N fertilization and yield target with respect to N supply and demand balance. The total amount of nitrogen and ratio of basal to top dressing nitrogen could be determined by this nitrogen fertilization model, and the desirable nitrogen fertilizer strategies could be made under the conditions of different climates, soil types and managements. Furthermore, the function of dynamic regulation of pre-designed N dressing rate could be determined by using the nitrogen fertilization model on the basis of actual growth status under a specific production system. The nitrogen fertilization model is evaluated using the data from field experiments of rice and wheat at Nanjing, and the results on crop growth pattern and N use showed that the grain yield and N recovery were markedly improved by the N fertilization plan given by the model. The nitrogen fertilization model can be used as guidance for quantifying N fertilization strategy in cereal crop production.     

氮磷钾运筹对不同小麦品种产量和品质的调节效应

为给小麦优质高产栽培提供理论依据,以强筋小麦品种济麦20和中筋小麦品种中麦175为试验材料,采用二因素随机区组设计,研究了氮磷钾运筹对小麦植株和产量性状、蛋白质和面筋含量、面团品质和烘焙品质的影响。结果表明,单施氮或氮磷、氮钾、氮磷钾配合施用,比单施磷、单施钾、磷钾配施以及不施肥处理显著增产,并改善了植株性状。施肥处理对籽粒蛋白质含量、面团品质和烘焙品质影响显著。籽粒产量性状和不同品质指标对施肥处理的反应有别,如施肥处理对产量、面团形成时间、稳定时间、拉伸面积影响较大,对容重、吸水率影响较小。不同品种的产量及品质指标对施肥处理的反应亦有差别,如中麦175的籽粒产量、面团拉伸阻力、拉伸比值、最大拉伸阻力、最大拉伸比值、面包体积和面包评分对施肥处理的反应敏感,其变异系数大于济麦20,而济麦20的面团形成时间、稳定时间对施肥处理的反应敏感,其变异系数大于中麦175。施氮对改善籽粒产量及主要品质性状的效果优于单施磷或单施钾处理。