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1.
大麦籽粒产量和氮积累的农艺因素效应   总被引:3,自引:1,他引:2  
本试验研究了密度及氮肥运筹对大麦籽粒产量和氮积累的影响。结果表明,在本地区以基本苗为172万/hm^2的群体籽粒产量最高,增加壮蘖肥和穗肥比例可明显提高植株器官氮含量和籽粒产量。明确了生产上宜采用的基本苗密度和氮肥运筹比例。  相似文献   

2.
饲用大麦扬饲麦3号优质高产栽培技术研究   总被引:3,自引:0,他引:3  
研究不同密度、氮肥用量及运筹比例对饲用大麦扬饲麦3号籽粒产量及主要品质指标的影响,结果表明:1、籽粒产量构成因素中穗数对于产量的贡献占主要作用,穗数与产量呈显著正相关;2、适当增加施氮量和氮肥运筹比例后移可以明显提高籽粒蛋白质与赖氨酸含量,饲用大麦扬饲麦3号籽粒的产量与蛋白质含量、赖氨酸含量呈正相关关系;3、扬饲麦3号以225万/hm2密度、氮肥用量225kgN/hm2、采用基肥∶壮蘖肥∶拔节肥为3∶3∶4运筹比例有利获得优质高产。  相似文献   

3.
密度与肥料运筹对小麦籽粒胚乳细胞发育的调节效应   总被引:3,自引:0,他引:3  
1994-1997年在扬州大学农学院作物栽培生理省级重点实验室试验,研究了密度,施氮量,氮磷钾配比及氮肥运筹方式对小麦籽粒胚乳细胞增殖与充实的调节效应。结果表明,密度和施肥运筹对胚乳细胞增殖及充实有显著调节效应,适当降低基本苗,增加施氮量并扩大后期追肥比例,提高磷钾肥施用比例,特别是增加拔节期磷,钾肥用量,能显著促进胚乳细胞分裂增殖和提高胚乳细胞充实度,从而增加粒重。  相似文献   

4.
播期、密度和氮肥运筹对瑞华麦520产量和品质的影响   总被引:2,自引:0,他引:2  
为确立抗病小麦品种瑞华麦520高产优质高效栽培管理措施,在大田研究了播期、密度、施氮量及氮肥基追比对瑞华麦520籽粒产量和品质的影响。结果表明,播期和密度对籽粒产量和品质均有明显影响,不同施肥量间差异显著,且播期效应大于密度和施肥效应。播期与密度试验中,10月10日播种、基本苗225万株·hm~(-2)时产量最高,10月10日后随着播期的推迟籽粒产量下降;籽粒蛋白质含量、湿面筋含量和面团稳定时间均随播期的推迟而增加;籽粒蛋白质含量随密度增加而降低,湿面筋含量和面团稳定时间受密度影响不大。氮肥运筹试验中,施氮量180~270kg·hm~(-2)范围内,籽粒产量随施氮量的增加而快速增加,施氮量超过270kg·hm~(-2)后产量增长缓慢;氮肥基追比7∶3时产量最高;籽粒蛋白质含量、湿面筋含量和面团稳定时间随着施氮量的增加而上升。综合分析,在本试验条件下,10月10日播种、基本苗225万·hm~(-2)、施氮量270kg·hm~(-2)、基追比7∶3时瑞华麦520可以获得更高的产量和品质。  相似文献   

5.
密度与肥料运筹对小麦籽粒胚乳细胞发育的调节效应   总被引:1,自引:0,他引:1  
1994~ 1997年在扬州大学农学院作物栽培生理省级重点实验室试验场 ,研究了密度、施氮量、氮磷钾配比及氮肥运筹方式对小麦籽粒胚乳细胞增殖与充实的调节效应。结果表明 ,密度和施肥运筹对胚乳细胞增殖及充实有显著调节效应 ,适当降低基本苗 ,增加施氮量并扩大后期 (拔节肥、保花肥 )追肥比例 ,提高磷钾肥施用比例 ,特别是增加拔节期磷、钾肥用量 ,能显著促进胚乳细胞分裂增殖和提高胚乳细胞充实度 ,从而增加粒重。  相似文献   

6.
氮肥和密度对冬小麦光合生理和物质积累的影响   总被引:5,自引:0,他引:5  
为给小麦高产栽培中氮肥和密度科学管理提供参考,以矮抗58和周麦22号为材料,研究了施氮量和播种密度对小麦植株光合生理、物质积累及产量性状的影响.结果表明,适量增施氮肥和增加密度能显著提高小麦叶面积指数、叶片叶绿素含量、净光合速率和群体干物质积累量,使植株在灌浆期仍能保持较高的光合能力,促进花后干物质的积累,有利于产量的提高.不同品种的籽粒产量对氮肥和密度的响应存在差异,周麦22号的平均籽粒产量高于矮抗58.在本研究条件下,矮抗58籽粒产量在375万基本苗·hm-2和360 kg·hm-2施氮量处理组合下最高;周麦22号籽粒产量在225万基本苗·hm-2扣240 kg·hm 2施氮量处理组合下最高.  相似文献   

7.
为给小麦高产、优质、高效栽培提供合理的氮肥运筹技术和理论依据,以强筋小麦品种济麦20为材料,应用15N示踪技术研究了高产麦田中施氮量和氮肥底施与拔节期追施的比例对小麦籽粒产量、品质和氮肥利用率的影响.结果表明,不同施氮处理之间植株氮素积累量无显著差异,小麦植株对追肥氮的利用率显著高于对底肥氮的利用率,适当增加追施氮肥的比例可提高氮肥利用率,其中以N2处理(施氮量为168 kg·hm-2,底追比例为1:2)最高.适量施氮并增加追施氮肥的比例可显著提高籽粒产量、蛋白质含量,改善籽粒加工品质,N2、N5(施氮量为240 kg·hm-4,底追比例为1:2)和N6(施氮量为240 kg·hm-2,全部追施)处理效果均较好.在本试验条件下,施氮量为168 kg·hm-2及底追比例为1:2的处理是兼顾产量、品质、效益和生态的合理氮肥运筹方式.  相似文献   

8.
为探索适宜的稻茬晚播小麦高产高效栽培技术,于2019-2021年进行播期(11月1日和11月25日)、施氮量(210 kg·hm-2和270 kg·hm-2)和氮肥运筹(基肥∶分蘖肥∶拔节肥分别为7∶1∶2、5∶1∶4和3∶3∶4)三因素裂区试验,研究施氮量、氮肥运筹组合对不同播期小麦产量、氮素积累量、氮素利用率及品质的影响。结果表明,播期推迟后适当增加基本苗有利于保持穗数稳定,降低减产幅度,与适播相比两个年度平均减产8.62%。增加施氮量能促进植株各生育阶段氮素吸收量,但降低氮肥偏生产力、氮素农学效率、氮素生理效率和氮素表观利用率,且导致产量下降;增加追肥比例促进小麦拔节后氮素吸收利用,有利于提高氮肥偏生产力、氮素农学效率和氮素表观利用率,但降低氮素生理效率。晚播条件下增加氮肥用量或提高追肥比例能提高籽粒蛋白质含量和湿面筋含量,对硬度无显著影响。在适播条件下,5∶1∶4氮肥运筹有利于协调穗数和粒重的关系,获得最高产量;在晚播条件下,3∶3∶4运筹通过降低基肥比例和提高分蘖肥比例,虽然使穗数略降,但提高穗粒数和千粒重,有利于产量形成。综上所述...  相似文献   

9.
为明确秸秆还田条件下稻茬小麦高产高效栽培的适宜播种密度和氮肥运筹方式,采用大田试验,以济麦22号为材料,研究了稻秸还田下不同播种密度(播量120kg·hm-2、180kg·hm-2)、施氮量(180、225和270kg N·hm-2)及氮肥基追比(基肥∶拔节肥∶孕穗肥为6∶3∶1、5∶3∶2和4∶3∶3)对小麦产量和氮素利用效率的影响。结果表明,在施氮量180kg·hm-2(低氮)和225kg·hm-2(适氮)下,提高播种密度显著提高了小麦叶面积指数、开花期旗叶光合速率、花后干物质积累量和籽粒产量;而在施氮量270kg·hm-2(高氮)下,提高播种密度显著降低了小麦生育后期叶面积指数、开花期旗叶光合速率、花后干物质积累量和籽粒产量。提高播种密度、降低施氮量均降低了土壤中无机氮的盈余量,氮肥吸收效率和氮肥农学效率显著提高。产量、氮肥吸收效率及氮肥农学效率均在氮肥基追比为基肥∶拔节肥∶孕穗肥=6∶3∶1时最大。因此,稻秸还田条件下提高小麦播种密度、适当降低施氮量并提高基肥比例,可以实现小麦产量和氮素利用效率的同步提高。  相似文献   

10.
施肥和密度对小麦产量及加工品质的影响   总被引:24,自引:6,他引:18  
为了探讨提高产量和改善品质的合理栽培措施,试验采用不同氮肥和密度处理,研究其对产量和品质的影响,结果表明:基本苗为225万~450万/hm2时产量差异不显著,但均比150万/hm2基本苗处理显著提高了产量。施氮270 kg/hm2比135 kg/hm2显著提高了产量。不同基本苗处理对蛋白质含量和加工品质指标影响较小,但不同施氮量对各蛋白组分、总蛋白质含量及加工品质指标有显著影响,高氮处理比低氮处理显著提高了总蛋白质和各蛋白组分含量,并显著增加了沉淀值、湿面筋含量、干面筋含量、吸水率、形成时间和面包体积。结论认为:基本苗对产量影响较大,对品质影响较小,施氮处理对产量和品质均有重要影响,适当增施氮肥可以使籽粒产量、营养品质和加工品质同步提高。  相似文献   

11.
Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described.  相似文献   

12.
13.
Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.  相似文献   

14.
Health authorities worldwide have consistently recommended the regular consumption of marine fishes and seafood to preserve memory, sustain cognitive functions, and prevent neurodegenerative processes in humans. Shrimp, crabs, lobster, and salmon are of particular interest in the human diet due to their substantial provision of omega-3 fatty acids (n-3/PUFAs) and the antioxidant carotenoid astaxanthin (ASTA). However, the optimal ratio between these nutraceuticals in natural sources is apparently the key factor for maximum protection against most neuro-motor disorders. Therefore, we aimed here to investigate the effects of a long-term supplementation with (n-3)/PUFAs-rich fish oil, ASTA-rich algal biomass, the combination of them, or krill oil (a natural combination of both nutrients) on baseline redox balance and neuro-inflammation indexes in cerebellum and motor cortex of Wistar rats. Significant changes in redox metabolism were only observed upon ASTA supplementation, which reinforce its antioxidant properties with a putative mitochondrial-centered action in rat brain. Krill oil imposed mild astrocyte activation in motor cortex of Wistar rats, although no redox or inflammatory index was concomitantly altered. In summary, there is no experimental evidence that krill oil, fish oil, oralgal biomass (minor variation), drastically change the baseline oxidative conditions or the neuro-inflammatory scenario in neuromotor-associated rat brain regions.  相似文献   

15.
Wheat bran is a composite material made of several layers, such as pericarp, testa and aleurone. It could be fractionated into purified fractions, which might either be used as food ingredients, or serve as a starting material for extraction of bioactive compounds. The aim of this work was to evaluate the potential of using electrostatic separation as a way to obtain purified fractions from wheat bran. Ultrafine-ground bran obtained either by cryogenic grinding or by grinding at ambient temperature was used as starting material. The ultrafine bran was then charged by tribo-electrification and introduced in a chamber containing two high voltage electrodes, where bran particles were separated depending on their acquired charge, allowing positively and negatively charged fractions to be collected separately. The particle size distribution, microstructure and biochemical composition of the obtained fractions were studied. The charge of the particles was influenced by their biochemical composition: particles rich in highly branched and cross-linked arabinoxylans (pericarp) were separated from particles rich in β-glucan, ferulic acid and para-coumaric acid (aleurone cell walls). The testa and the intracellular compounds from aleurone were not highly charged, neither positively nor negatively. The most positively charged fraction represented 34% of the initial bran, and contained 62% of the ferulic acid present in the initial bran. The yield of the separation process was good (5.4% loss), and could be further increased.  相似文献   

16.
Novel food and non-food uses for sorghum and millets   总被引:4,自引:3,他引:4  
Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.  相似文献   

17.
Pulque is made by fermenting the agave sap or aguamiel of Agave atrovirens with a whole array of microorganisms present in the environment including several lactic acid bacteria and yeasts such as Saccharomyces cerevisiae. Ascorbic acid was determined in pulque and aguamiel, respectively. Phytase activity in lees, liquid and freeze-dried pulque was assayed by measuring the appearance of phosphate from phytate by a colorimetric method likewise phosphate from phytate present in fresh corn tortilla was measured after in vitro incubation with pulque. Iron, zinc, calcium, magnesium and selenium contents were measured in pulque and corn tortilla as well as in nixtamalized corn flour (NCF), the latter is used to make instant tortilla, since corn provides most of the energy as well as most of the phytate in the Mexican rural diet. Pulque showed phytase activity but much less ascorbic acid and iron than previously reported; additionally, phytase in pulque hydrolyzed most of phytate’s corn tortilla. Lees, which is mostly made of pulque’s microbiota, significantly accumulated iron and zinc but no selenium. NCF was fortified with iron by the manufacturers but poorly blended. There were significant differences on selenium content between tortillas samples, apparently some soils in central Mexico are selenium deficient. Moderate pulque intake appears to increase the bioavailability of iron and zinc bound by phytate in corn.  相似文献   

18.
Summary Recurrent backcrosses (BC) were used to introduce nuclear factors ofS. tuberosum L. ssp.tuberosum into the cytoplasm of Andean potatoesS. tuberosum ssp.andigena (Juz. and Buk.) Hawkes andS. phureja Juz. and Buk. Each generation BC was produced in reciprocal directions to test the effect of cytoplasmic substitution on yield. This report analyses tuber number, tuber weight, and tuber length of BC2 and BC3 substitution into ssp.andigena cytoplasm and BC2 and BC2 substitutions intoS. phureja cytoplasm. Direction of cross had no consistent significant effect on yield components of ssp.andigena substitution lines. InS. phureja reciprocal progenies direction of cross was responsible for significant differences of some reciprocal sets. When there were significant differences the higher yield usually occurred when ssp.tuberosum was the pistillate parent, but in some progenies when ssp.tuberosum was the pistillate parent the yield was significantly lower than in the reciprocals. It is suggested that differences between reciprocals resulted from chromosomally encoded gene action, resulting from maternal and/or paternal effects, rather than cytoplasmic factors. Authorized for publication as paper No. 7494 in the Journal Series of The Pennsylvania Agriculture Experiment Station.  相似文献   

19.
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   

20.
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.
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