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1.
不同施氮量对麦茬夏花生氮素吸收分配及产量的影响   总被引:1,自引:0,他引:1  
大田栽培条件下,研究不同氮肥施用量对麦茬夏花生植株生长、氮素吸收、土壤养分及产量构成的影响。结果表明:不同施氮量对土壤硝态氮含量的影响主要以表层(0~20cm)较为显著,且硝态氮存在向下层土壤迁移的趋势;各处理不同土层间土壤铵态氮含量均无显著差异。0~225kg/hm~2范围内,随着施氮量的增加,夏花生产量逐渐提高。氮肥施用量在225kg/hm~2条件下,花生产量最高,为6603.26kg/hm~2,比不施用氮肥增产19.96%;达到300kg/hm~2氮肥施用量时,会促进花生茎叶部的氮素积累,但同时会抑制花生根部和荚果的氮素积累,产量反而会降低。总体而言,随着施氮量的增加,氮肥利用率呈现先升高后降低的趋势,氮肥偏生产力则呈显著下降趋势,本试验条件下N最佳施用量为244.70kg/hm~2。  相似文献   

2.
在大田试验条件下,研究了不同氮肥用量对仁秆两用型花生叶片光合特性及产量品质的影响.结果表明,花生荚果与花生秆产量随着施N量的增加呈先增加再减少的变化趋势,分别在施N肥300kg/hm2处理时产量达到最高,其中花生荚果产量比对照增产2.2%,但差异不显著;花生秆产量比对照增产86.0%,达极显著水平.对不同施氮量下花生光合特性的研究表明,花生功能叶片的光合速率随着氮肥用量的加大出现升高再下降的趋势,在施N肥300kg/hm2达到最高,随着氮肥用量的加大,花生功能叶片的气孔导度和蒸腾速率呈逐渐下降趋势.品质方面随施氮量的增加,花生秆粗蛋白含量呈极显著提高,但较高的氮肥施用量虽然可提高花生秆的营养品质,却降低了花生荚果和花生秆的产量.综合评价认为,在本试验条件下,在施N量300kg/hm2时花生荚果及花生秆产量最高,花生秆品质最好.  相似文献   

3.
种植密度和氮肥水平对花生产量的影响   总被引:1,自引:0,他引:1  
在田间条件下,分别设置高、中、低3个种植密度和3个氮肥用量,采用二因素三水平随机区组设计,研究氮肥用量与种植密度对花生产量的互作效应,以期对高产花生群体构建和高产高效栽培提供指导。试验结果表明,回归方程曲面图为马鞍形,高、低种植密度条件下,产量随着氮肥用量的增加表现先升后降,中等氮肥用量时产量最高,表明高密度和追施中等水平氮肥可获得高产。因此,种植密度和追施氮肥量对花生产量具有明显的互作效应。  相似文献   

4.
施肥、品种及密度对大豆籽粒异黄酮含量的影响   总被引:1,自引:0,他引:1  
大豆异黄酮由于其特定生理保健功能而受到越来越广泛的关注.2006年进行了砂培试验,用以探索氮、磷、钾肥单因素对大豆籽粒异黄酮含量的影响规律.结果表明:氮肥对大豆籽粒异黄酮总含量有较大影响,低氮处理较高氮处理异黄酮总含量增加54.9%,低氮处理较均衡施肥异黄酮总含量增加23.3%.2007年进行了氮肥施用量、品种与栽培密度3因素田间试验.结果表明:品种、密度、施氮量3项效应及其所有的互作项对大豆籽粒异黄酮总含量与3种组分含量均具有极显著的效应.氮肥施用量对大豆籽粒异黄酮含量的影响规律与砂培试验的结果一致,即大豆籽粒异黄酮总含量随氮肥施用量的增加而降低.不同氮肥施用量、不同密度水平及不同品种间异黄酮总含量的变异幅度为5.97%、10.49%和28.44%.由于单项因素及互作项效应的存在,在进行高低异黄酮大豆栽培生产时,考虑各单项因素的同时也应注意各项因素不同水平的最佳组合.  相似文献   

5.
本研究旨在探讨单粒精播花生生理性状和产量性状对密度和氮肥的响应。选择山东省烟台市招远鲁东丘陵地,作物两年三熟。2018和2019年,以出口大花生品种花育22为试验材料进行大田试验,设置了3个种植密度(12万、20万、28万株/hm2,分别表示为D1、D2和D3)和4个施氮量(0、50、115、180 kg/hm2,分别表示为N0、N50、N115、N180),于不同生育时期调查分析花生SPAD值、植株和产量性状。研究结果表明,种植密度和施氮量均显著影响花生叶绿素含量、干物质量、植株性状和产量性状,且两者互作效应显著。在D2密度条件下,花生荚果产量较D1密度和D3密度分别高24.31%~45.04%和10.57%~15.13%,成熟期叶绿素含量分别高3.70%~27.82%和6.10%~18.94%,成熟期干物质量分别高7.31%~32.34%和10.65%~34.59%,且差异性均达到了显著水平。在D2密度下,施氮量在50~180 kg/hm2范围内,花生荚果产量、叶绿素含量和干物质量均显著高于无氮处理,各施氮处理表现为N115 > N180 > N50 > N0,以施氮量为115 kg/hm2时花生荚果产量最大,较N50和N180处理分别提高了6.83%和3.90%,叶绿素含量、干物质量和植株性状也协同提高。综合考虑生理性状、产量性状等因素,在本试验条件下,单粒精播花生栽培在低密度12万株/hm2下,花生主要产量性状随着施氮量的增加而增加,以种植密度为20万株/hm2,施氮量为115 kg/hm2较为适宜。  相似文献   

6.
高洪儒 《北方水稻》2014,44(5):28-29
对6个香型水稻品种进行4个不同施肥量处理,得出在种植香型水稻品种时,施氮量超过12 kg/667 m2导致倒伏严重、整精米率降低、垩白米率增加、直链淀粉含量增加、蛋白质含量增加、综合评价值降低;施氮量在8 kg/667 m2时,倒伏较轻,稻米品质较好;施氮量在10 kg/667 m2时,部分品种倒伏严重、稻米品质开始下降。因此,在种植香型水稻品种时,氮肥施用量最好不超过10 kg/667 m2,要想达到较好的品质,氮肥施用量最好在8 kg/667 m2。  相似文献   

7.
为给宁盐一号小麦品种的高产优质栽培提供依据,2003~2004年在江苏沿海地区农科所试验场,研究了不同氮肥施用量和基本苗对该品种籽粒产量与蛋白质及其组分含量的影响.结果表明,在基本苗相同时,增加氮肥施用量,每穗粒数、蛋白质及其组分含量提高,而千粒重降低.在基本苗90×104~180×104/ha范围内提高氮肥施用量,可增加穗数、花后干物质积累量、抽穗期群体LAI和产量,基本苗超过270×104/ha则表现为负效应.在氮肥施用量相同时,基本苗增加,每穗粒数、蛋白质及其组分含量均呈下降趋势.在施氮量180 kg/ha条件下,增加基本苗,穗数相应增加.综合来看,宁盐一号高产优质栽培的适宜氮肥和密度组合为施氮量180 kg/ha、基本苗270×104/ha或施氮量240 kg/ha、基本苗180×104/ha.  相似文献   

8.
利用正交试验,对影响杂交稻新组合Ⅱ优129产量的三个主要栽培管理因素:氮肥施用方法、种植密度、纯氮施用量进行初步分析,结果表明,每667m2中插植1.5万穴,基肥中氮肥占总施氮量70%,每667m2施用纯氮15kg可实现较高的产量水平.  相似文献   

9.
通过多年多点的五因素二次通用旋转组合设计试验,以对春小麦生育影响较大的基本苗数、施磷量、施钾量、种氮肥量、追氮肥量五项主要因素为决策变量,以产量为目标函数,建立了内蒙古小麦主产区主要农艺栽培措施与产量关乐的二次多项式回归数学模型,通过频数寻优,定量化提出了灌区春小麦实现高产的综合农艺栽培措施优化组合方案.密度、氮、磷、钾肥施用量对产量影响均呈单峰曲线变化,其中以种氮肥、施钾量影响较大;氮、磷、钾肥花用量较少时,密度与氮、磷、钾肥施用量的交互作用为正效应,反之,则为负效应。  相似文献   

10.
[目的]研究氮肥施用量对大棚黄瓜品质的影响。[方法]以河北省衡水市邓庄乡大棚黄瓜为试验材料,研究不同施氮条件下,黄瓜体内Vc、多糖、硝酸盐含量的变化。[结果]当施氮肥小于225kg/hm2,黄瓜体内的Vc、多糖含量随着施氮量的增加而升高,当施氮量为225kg/hm2时,Vc、多糖含量最高;过量施用氮肥会引起Vc、多糖含量的下降;硝酸盐含量和施氮量呈明显的线性关系,Y=1.502X+24.407(R2=0.9792),所测样品均未超过国家限定标准。[结论]该试验条件下最佳施氮量为225kg/hm2,过少或过量的施肥均不利于黄瓜产量和品质的形成。  相似文献   

11.
Pasture legumes are important components of both mixed farming rotations and permanent pastures in temperate climates. Breeding of two widely sown pasture legumes, subterranean clover (Trifolium subterraneum L.) and French serradella (Ornithopus sativus Brot.), is constrained by the long generation cycle, typically enabling only one generation per year. We hypothesized manipulation of culture medium and conditions would enable the development of a laboratory‐based protocol for in vitro reproduction in subterranean clover and French serradella. In vitro flowering and viable seed set was induced from both species. For subterranean clover, the most effective treatment was culturing on modified MS medium with 1 μm kinetin and 0·1 m sucrose under a 100 μmol m?2 s?1 light intensity and continuous photoperiod. For French serradella, culture on a hormone‐free B5 medium with 5 mm NH4Cl and 0·1 m sucrose under a 100 μmol m?2 s?1 light intensity and 20 h photoperiod was optimum. It is expected this technique will have application in accelerating generation turnover within breeding programs, for the study of factors influencing flowering in pasture legumes, and for the propagation of valuable yet enfeebled plants such as embryo‐rescued hybrids.  相似文献   

12.
Marine organisms represent an excellent source of innovative compounds that have the potential for the development of new drugs. The pharmacokinetics of marine drugs has attracted increasing interest in recent decades due to its effective and potential contribution to the selection of rational dosage recommendations and the optimal use of the therapeutic arsenal. In general, pharmacokinetics studies how drugs change after administration via the processes of absorption, distribution, metabolism, and excretion (ADME). This review provides a summary of the pharmacokinetics studies of marine-derived active compounds, with a particular focus on their ADME. The pharmacokinetics of compounds derived from algae, crustaceans, sea cucumber, fungus, sea urchins, sponges, mollusks, tunicate, and bryozoan is discussed, and the pharmacokinetics data in human experiments are analyzed. In-depth characterization using pharmacokinetics is useful for obtaining information for understanding the molecular basis of pharmacological activity, for correct doses and treatment schemes selection, and for more effective drug application. Thus, an increase in pharmacokinetic research on marine-derived compounds is expected in the near future.  相似文献   

13.
Evaluation of crop and forage yield stability is of increasing relevance in the context of current and recent environmental changes but, in contrast to other field crops, there are no published systematic analyses among forage crops in Europe. A study of stability performance was conducted with 13 Czech cultivars of lucerne at four locations over a 2‐year period with the following aims: (a) to evaluate yield stability of varieties across different environments and (b) to calculate measurable benefits of variety selection in relation to the specific environment. The cultivar Vlasta was identified as the highest yielding cultivar (annual yield 16.0 t DM/ha), whereas the lowest yielding cv. Magda, Tereza and Oslava averaged around 14.9 t DM/ha. Effect of genotype × environment interaction (G × E) was two times higher than for genotype alone. Additive main effects and the multiplicative interaction (AMMI) model showed that the highest yielding cultivars may not be stable across environments. This study demonstrated further that significant yield improvement could be detected, even among a relatively homogenous group of domestic cultivars, and this was driven mainly by site productivity: the improvement was +10% in low‐yielding sites, compared with +3% in high‐yielding sites. Results highlight that advanced agronomy should also consider stability parameters such as AMMI stability value or superiority measures for forage crops in response to the challenges associated with climate change.  相似文献   

14.
Résumé Fusarium culmorum et, dans une moindre mesure,F. avenaceum, F. sambucinum, Colletotrichum coccodes etCylindrocarpon sp. ont été isolés de tubercules entreposés en atmosphère contr?lée (AC) et atteints de pourriture grave. Des expériences d'inoculation de tubercules avec 10 espèces ou variétés fongiques et conservation en AC à 8 et 10°C ont montré que: 1) les champignons non pathogènes en atmosphère normale (ex.:Cylindrocarpon sp.) le devenaient en AC, 2) ceux qui étaient faiblement pathogènes en atmosphère normale étaient nettement plus virulents en AC (ex.:F. culmorum), 3) les espèces ou variétés virulentes en conditions d'air normales (Fusarium sulphureum etPhoma exigua var.foveata) ne provoquaient pas de pourriture plus grave en AC et leur activité pouvait même être légérement freinée.
Summary The extensive rotting of tubers which occurred during storage trials in controlled atmospheres has led to a mycological and pathological study of the rots. The most frequently isolated species wasFusarium culmorum althoughF. avenaceum, F. Sambucinum, Coletotrichum coccodes and aCylindrocarpon sp. were also present. Tubers of cvs Bintje and Ulla were inoculated with 19 isolates of 10 fungal species or varieties associated with rotting of stored tubers (Table 1). The tubers were incubated at 8 or 10°C in normal or controlled (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2) atmospheres and the extent of rotting was determined a month later (Tables 2 and 3 and Fig. 2). Species which were weakly virulent in a normal atmosphere (variousFusarium spp. andPhoma exigua var.exigua) were clearly more aggressive in the controlled atmosphere and this was especially evident in the case ofF. culmorum. Species ot pathogenic in a normal atmosphere under experimental conditions (Colletotrichum coccodes, Cylindrocarpon sp.,Phoma eupyrena) caused rotting in the controlled atmosphere. The two species which were virulent in a normal atmosphere (F. sulphureum andP. exigua var.foveata) were also virulent in the controlled atmosphere and in some cases the extent of rotting was even less. As a general rule, rotting caused by weakly virulent fungi was greater in both cultivars in the controlled than in a normal atmosphere.

Zusammenfassung Eine starke F?ulnis von in Kontrotrollierter Atmosph?re gelagerten Kartoffelknollen veranlasste eine mykologische und pathologische Untersuchung. Der am h?ufigsten isolierte Pilz warFusarium culmorum. F. avenaceum, F. sambucinum, Colletotrichum coccodes undCylindrocarpon sp. wurden ebenfalls bestimmt. Neunzehn St?mme von 10 Pilzsorten oder-Arten welche bei Lagerf?ulnis vorkommen (Tab. 1) wurden auf Knollen der Sorten Bintje und Ulla inokuliert. Die Lagerung wurde bei 8 oder 10°C under Normalbedingungen oder kontrollierter Atmosph?re durchgeführt (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2). Der F?ulnisgrad (Abb. 1) wurde nach einem Monat bonitiert. Die Ergebnisse sind in den Tabellen 2 und 3 dargestellt und in der Abb. 2 illustriert. Unter in Normalbedingungen nur schwach virulente Arten (verschiedeneFusarien undPhoma exigua var. exigua) waren deutlich aktiver in kontrollierter Atmosph?re. Dies was besonders der Fall fürF. culmorum. Pilze, die im Versuch unter Normalbedingungen nicht pathogen waren (Colletotrichum coccodes, Cylindrocarpon sp., Phoma eupyrena), haben unter kontrollierter Atmosph?re Sch?den verursacht. Hingegen werden die beiden unter Normalbedingungen sehr pathogenen Arten (F. sulphureum undP., exigua var.foveata), durch kontrollierte Atmosph?re wenig beeinflusst. Es wurde sogar in einigen F?llen eine gewisse Verringerung des F?ulnisbefalls beobachtet. Ganz allgemein haben die getesteten kontrollierten Bedingungen die Entwicklung der Pilzf?ulnis an beiden Kartoffelsorten gef?rdert, speziell durch Pilzarten, welche unter Normal-bedingungen wenig Sch?den verursachen.
  相似文献   

15.
The review of the 2016–2017 marine pharmacology literature was prepared in a manner similar as the 10 prior reviews of this series. Preclinical marine pharmacology research during 2016–2017 assessed 313 marine compounds with novel pharmacology reported by a growing number of investigators from 54 countries. The peer-reviewed literature reported antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral activities for 123 marine natural products, 111 marine compounds with antidiabetic and anti-inflammatory activities as well as affecting the immune and nervous system, while in contrast 79 marine compounds displayed miscellaneous mechanisms of action which upon further investigation may contribute to several pharmacological classes. Therefore, in 2016–2017, the preclinical marine natural product pharmacology pipeline generated both novel pharmacology as well as potentially new lead compounds for the growing clinical marine pharmaceutical pipeline, and thus sustained with its contributions the global research for novel and effective therapeutic strategies for multiple disease categories.  相似文献   

16.
SUMMARY

Vitamin A, iodine, and iron deficiencies affect large numbers of people worldwide. A deficiency of one or more of these micronutrients adversely affects the physical and mental abilities of humans. South Asia contains a high percentage of these individuals, not just because of its large population, but also the prevalence of deficiency is higher there than in many other parts of the world. The reasons for the high rates of deficiency in South Asia are many, but they include inadequate availability of micronutrient-rich foods, sub-optimal dietary habits, and high rates of infection. Across the region, national plans vary from (a) increasing availability of appropriate foods, (b) introducing new dietary behaviors, (c) improving health status, and (d) directly addressing deficiency through intervention programs. The extent to which each of the countries is making progress toward the goals of these plans can help in understanding the priorities for future efforts to address micronutrient malnutrition. This article discusses the adverse effects of micronutrient deficiencies in humans with special reference to South Asia.  相似文献   

17.
东南亚、南亚地区是世界上重要的稻米产区,稻米在民众饮食生活和国家社会政治中占有重要地位,民众生活中也保存了非常悠久和丰富的稻作文化习俗及稻谷起源神话传说。本文分析了水稻在东南亚、南亚主要国家印度、印度尼西亚、泰国、越南、菲律宾、孟加拉国、缅甸的作用、地位、生产、消费、文化等情况,并指出了印度、印度尼西亚稻文化的主要标志。  相似文献   

18.
Plains rough fescue ( F estuca hallii) is an important forage grass species in western Canada. Seed for use in pastures and ecological restoration is in high demand but supply is limited because F. hallii is an erratic seed producer. Seed producers require an understanding of the factors that influence flowering and seed set in this species. The aim of this study was to assess the effect of irrigation and nitrogen fertilization on the flowering and growth of F. hallii in a native rough fescue prairie in Alberta, Canada. Irrigation had a strong positive effect on seedhead density, whereas fertilization had limited effects on growth and reproduction of F. hallii. These results demonstrate that under field conditions, available moisture is likely to be a key factor driving flowering and seed production in F. hallii.  相似文献   

19.
Summary

Within the last three decades, the rice-wheat cropping system has triggered, and with time, aggravated soil micronutrient deficiencies in the Indo-Gangetic Plains (IGP). This has largely been due to the shift from an earlier rice and wheat monoculture with low yielding, long duration indigenous varieties, to an intensive rice-wheat rotation cropping system with short duration modern high yielding varieties on the same piece of land. The problems related to micronutrient deficiency in the IGP are more due to the size of its available pools in the soil rather than its total contents and are greatly influenced by crop management, or rather its mismanagement. Deficiency of zinc is widespread in the IGP, but with the extensive use of zinc sulfate, zinc deficiency has reduced in some areas of the region. Meanwhile, the deficiency of Fe, Mn and B has increased in the IGP. Deficiency of Cu and Mo is location specific and can limit rice and wheat yields. The adoption and spread of the rice-wheat system in permeable coarse textured soils, particularly in the western IGP, not only caused iron deficiency in rice but also resulted in the emergence of manganese deficiency in wheat. In highly calcareous and acidic soils, boron is the next limiting micronutrient in crop production after zinc. Bumper rice and wheat harvests in the past decade, the declining use of organic manures in the region and except for the widespread use of zinc sulfate, a general lack of awareness amongst farmers on micronutrient deficiency problems has contributed to micronutrients limiting rice and wheat yields in the IGP. Approaches to alleviating micronutrient deficiencies include matching the crop removals of the micronutrients with its replenishments through their respective external carriers, supplementation through organic sources and mobilization/utilization through cultivation of micronutrient efficient crop cultivars. Identification of efficient micronutrient carriers and finding the optimum rate, mode and time of its application is important in ameliorating the micronutrient deficiencies. This article reviews the extent of micronutrient deficiency and discusses various management options available to reduce micronutrient deficiency induced crop yield reduction for rice and wheat in the Indo-Gangetic Plains.  相似文献   

20.
A general model of crop yield response to herbicide application is proposed. The model includes three components: the effect of herbicide dosage on weed density, the effect of surviving weed density on crop yield and the effect of herbicide directly on the crop. The model is used to estimate the response of wheat yield to application of diclofop-methyl to control ryegrass (Lolium rigidum) in Australia. It is found that the competitiveness of ryegrass plants surviving treatment is reduced by the treatment and that the proportion of yield loss at a given ryegrass density is not independent of the absolute weed-free yield. The response function is used to calculate economic thresholds and optimal herbicide dosages.  相似文献   

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