种植密度和氮肥及其互作对邵阳烟区稻茬烤烟经济性状的影响

为明确邵阳烟区稻茬烤烟的种植密度和施氮量,采用偏Eta2值分析了种植密度和施氮量及其互作对烤烟经济性状的效应。结果表明:1种植密度和施氮量及其互作对不同烤烟经济性状指标的效应不一样,种植密度对烤烟上中等烟比例、均价和产值具有显著的高度影响;施氮量对烤烟均价、产量和产值具有显著的高度影响;种植密度和施氮量互作对烤烟上中等烟比例、均价、产量和产值具有显著的高度影响。2种植密度和施氮量及其互作主要影响烤烟均价。3对烤烟经济性状的影响以互作最大,占37%左右;其次是施氮量,占35%左右;种植密度最小,占28%左右。4邵阳稻茬烟区烤烟生产以种植密度16 667~18 182株/hm2、施氮量120~135 kg/hm2为好。     

种植密度和施氮量对粮饲兼用玉米雅玉8号产量的影响

研究了不同种植密度和施氮量对粮饲兼用玉米品种雅玉8号产量的影响。结果表明,雅玉8号的最佳种植密度为9.75万株/hm2,最佳施氮量为337.5kg/hm2,鲜物质产量达71032.10kg/hm2,干物质产量达22820.10kg/hm2,果穗干物质产量达11547.64kg/hm2。通过对种植密度和施氮量与生物产量之间的关系建立的回归模型预测可知,当种植密度为10.68万株/hm2、施氮量为273.48kg/hm2时能获得最高的鲜物质理论产量70798.72kg/hm2;当种植密度为11.13万株/hm2、施氮量为280.52kg/hm2时能获得最高的干物质理论产量22936.30kg/hm2。种植密度和施氮量对雅玉8号生物产量及果穗产量的影响均达极显著水平。     

施氮量与种植密度对烤烟生长发育及经济性状的影响

为探索施氮量和种植密度对烤烟生长发育及经济性状的影响,2013年在常宁市进行了氮肥与密度试验。结果表明:相同密度下的烤烟产量与产值随着施氮量的增加而增加,其中施氮157.5、180 kg/hm2的处理其烤烟产量分别比施氮135 kg/hm2处理高6.59%和18.07%,其产值分别高126.0和5488.8元/hm2,单位养分产量分别高79.8和109.5 kg/hm2,单位面积净收益分别高747.6和3639.6元/hm2;且最大施氮量处理产量显著高于其余处理;均价随着施氮量增加而递减。在施氮量157.5 kg/hm2水平下,采用1.2 m×0.4 m和1.2 m×0.5 m种植密度,烟叶产量和效益最佳。     

施氮量与密度对浏阳烤烟产质量的耦合效应

为探讨施氮量与密度对浏阳烤烟经济性状与烟叶品质的耦合效应,在3个施氮量(A1:150 kg/hm~2、A2:180 kg/hm~2、A3:210 kg/hm~2)和3个密度(B1:15 000株/hm~2、B2:16 500株/hm~2、B3:18 000株/hm~2)下开展了大田试验。结果表明:(1)本试验条件下,烟叶产量与产值均随施氮量和密度增大表现先增后降趋势,以A2B2、A2B3处理对产量与产值的耦合效应最佳;(2)施氮量与密度明显影响烤后烟叶物理性状,A3B1处理单叶重最大,A2B1和A2B2处理烟叶含梗率最低;(3)烤后烟叶外观质量受密度影响小,受施氮量影响较大,A2处理烤后烟叶外观质量最好;(4)施氮量与密度耦合对烤后烟叶化学成分及其协调性影响显著,综合烟碱、钾含量以及化学成分协调性指标,中部烟叶以A2B3处理化学品质最好,上部烟叶以A2B2处理化学品质最好。综合来看,施氮量180 kg/hm~2和密度16 500~18 000株/hm~2对浏阳烟区烤烟产量、产值和烟叶品质的耦合效应最佳。     

种植密度、施氮量对有机烟叶产质量的影响

为探索有机烟叶生产的合理施氮量和密度,2009年在凤冈县进化镇进行了不同密度、施氮量对有机烟叶产量、质量的影响试验.结果表明:1)不同密度、施氮量对有机烟叶大田生育期影响不明显;2)在施氮量82.5 kg/hm2、种植密度18000株/hm2条件下,烟叶田间长势良好,上等烟率、上中等烟率、橘黄烟率和内在化学成分协调性较好,产值和产量最大.     

郑单958不同密度与施氮量对产量及部分植株性状研究初报

通过对郑单958不同密度和不同追施氮肥量的研究结果表明:在基施绿源复合肥600kg/hm2的条件下,郑单958的最佳种植密度为75000株/hm2,追施氮肥量为270kg/hm2,产量10108.31kg/hm2,增加利润1433.00元/hm2。不同密度间产量差异不显著,不同施氮量间产量差异达显著水平。     

密度和施氮量对雅玉8号青贮玉米产量和品质的影响

研究不同种植密度和施氮水平对雅玉8号产量及品质的影响。结果表明,雅玉8号在四川资阳地区适宜种植密度为90 000株/hm2,最佳施氮量为200 kg/hm2,其地上干物质产量高达23 345 kg/hm2,果穗率为59.93%,粗蛋白含量为75.5 g/kg,粗纤维仅为124 g/kg,粗脂肪、粗灰分、无氮浸出物和钙含量分别为34.6、62.0、598和4.0 g/kg。种植密度和施氮水平对青贮玉米的地上干物质含量、粗蛋白产量及果穗率和粗纤维含量的影响均呈显著水平。     

不同施氮量及氮磷钾配比对烤烟产量与质量的影响

为了确定湖南茶陵烟区种植烤烟的适宜施氮量及氮钾比例,2010年在茶陵腰陂镇芙冲村进行了不同施氮量及氮钾比的小区对比试验。结果表明,不同的氮肥用量对烤烟的生长发育有明显的影响,随着氮肥用量的增加及氮钾比例的升高,烟株的茎围、株高、有效叶数、腰叶的长宽、产量均随之增加,但当施氮量超过180 kg/hm^2,氮钾比例（N∶K）超过3后,烤烟的产值、上中等烟比例及内在化学成分的协调性均有所下降。综合结果表明,施纯氮180 kg/hm^2、N∶P∶K=1∶0.8∶3的处理烤烟产量和质量处于最佳效果。     

密度与施氮量对烤烟农艺性状及烟叶主要化学成分的互作效应

采用田间裂区试验,研究了3种种植密度(主处理)与3个施氮水平(副处理)对烤烟农艺性状及烤后烟叶主要化学成分含量的互作效应。研究表明,种植密度与施氮量对烤烟的株高及烤后烟叶的总糖、还原糖、总氮、烟碱等主要化学成分含量的影响存在显著交互作用;对烤烟农艺性状的调控作用表现出阶段性差异和"剂量效应";对主要化学成分含量的调控因部位、化学成分指标不同存在差异。以移栽密度18 525株/hm2与施氮量120 kg/hm2对促进烤烟生长与改善烤后烟叶化学成分含量的效应最好。     

种植密度和施氮量对辽单527产量的影响

以玉米杂交种辽单527为试材,研究不同种植密度和氮肥量对产量的影响。结果表明,随着种植密度和施氮量的增加,辽单527的产量呈先升高后下降的趋势。通过建立二元二次回归方程得出,种植密度为61 000株/hm2、施氮量在149 kg/hm2时辽单527理论产量最高,灌浆期穗位层叶面积指数也较高。     

Comparative Assessment of the Efficacy of Various Nitrogen Fertilizers

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.     

Novel food and non-food uses for sorghum and millets

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.     

Pharmacokinetics of Marine-Derived Drugs

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.     

La pourriture fongique des tubercules de pomme de terre en atmosphère contrôlée

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.

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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.

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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.

     

Citrus Flavonoids in Fruit and Traditional Chinese Medicinal Food Ingredients in China

Flavonoids-enriched tissues of citrus such as peel, immature fruit and flower are consumed as culinary seasonings, tea ingredients in China for centuries. This HPLC quantitative study on the five citrus flavonoids, naringin, hesperidin, neohesperidin, sinensetin and nobiletin on a wide range of Chinese citrus fruits and several Traditional Chinese Medicinal food ingredients in East China, revealed a great diversity in flavonoid composition. Huyou peel (C. paradisi cv. Changshanhuyou) was found to be the best naringin (3.25%) and neohesperidin (2.76%) source; C. aurantium, a major ingredient of several citrus-related TCM, is also a suitable source of naringin and neohesperidin, and a good juice source for flavanone glycosides; the peel of Wenzhoumiju (C. unshiu) is one of the richest local species in hesperidin (up to 6.25%); Zaoju (C. subcompressa) has the highest content of nobiletin (0.59%), a polymethoxylated flavone. LC-ES-MS analysis of Zanthoxylum genus for flavonoids revealed for the first time the presence of significant amounts (0.74%) of hesperidin in the root of Liangmianzhen (Z. nitidum (Roxb.) DC), a relative of Sichuan pepper, which is a spice widely used in China.     

Evolutionary aspects of the trade-off between seed size and number in crops

Whereas the concept that availability of resources drives seed production is sound in principle, it is incomplete as there are many solutions to the allocation of resources that derive from the trade-off between number and size. This paper examines evolutionary aspects of this trade-off in annual grain crops. The analysis is centred on the working hypotheses that, for a given species and environment, allocation of resources to reproduction involves (H1) high plasticity in seed number, which allows for variable resource availability, and (H2) a relatively narrow range of seed size that results from evolutionary and agronomic selection. Comparisons between crops and fish are used to highlight common evolutionary elements in taxa where parents provide little or no care to their offspring, with the consequence that both number and early survival of offspring, hence fitness of parents, are partially related to embryo size and reserves.

The plasticity of seed number in relation to availability of resources is analysed against the established relationship between offspring number and parent growth rate during critical stages. The notion that seed size is under stabilising selection is analysed against three conditions: (1) mean seed size is conservative for a given species and environment, (2) seed size affects fitness, and (3) seed size is heritable. Databases from published papers were compiled to analyse the relative variability of seed size and number, and the heritability of seed size. Evidence for and against the link between seed size and parental fitness is revised using the Smith–Fretwell model as framework (Am. Nat., 108, 499–506).

The proposal of high plasticity of seed number and narrow variability of seed size resulting from stabilising natural selection is generally consistent with evolutionary and genetic considerations. Agronomic selection may have reinforced natural selection leading to relatively narrow seed size in species such as wheat and soybean, where cultivated types retained high plasticity for seed number. In contrast, selection for one or few inflorescences in crops like sunflower and maize may have morphologically reduced seed number plasticity and increased variability of seed size and its responsiveness to resource availability in relation to their wild ancestors.     

Marine Pharmacology in 2016–2017: Marine Compounds with Antibacterial,Antidiabetic, Antifungal,Anti-Inflammatory,Antiprotozoal, Antituberculosis and Antiviral Activities; Affecting the Immune and Nervous Systems,and Other Miscellaneous Mechanisms of Action

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.     

Effects of Micronutrient Deficiencies on Human Health: Its Status in South Asia

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.     

Effect of a continuous hot water treatment of potato tubers on seed-borne fungal pathogens

Summary The viability of five pathogens was decreased by treatment with hot water when tested in vitro.Polyscytalum pustulans was most sensitive andRhizoctonia solani least sensitive. Potato tubers were exposed to 55°C for 5 min in a commercial continuous hot water treatment plant using naturally contaminated seed tubers and tubers which had been inoculated by dipping in comminuted cultures. The frequency of eyes colonised byP. pustulans, Helminthosporium solani, andR. solani was reduced to virtually zero and the effect persisted on tubers subsequently stored at 4°C and at 15°C for up to 16 wk. Results withColletotrichum coccodes were inconclusive. Treatment suppressedPenicillium spp. which, however, rapidly recolonised the eyes during storage, leading to higher contamination levels in the treated than in the untreated tubers. With tubers inoculated withPhoma foveata, good control was achieved when the incubation period before treatment was 10 d but not when the period was 42 d.