氮、磷、钾肥对作物的增产效果与适宜施用量的探讨

根据近几年来南安市甘薯、花生、马铃薯作物主产区田间肥料试验结果,认为施用氮、磷、钾肥能有效地增加马铃薯、花生植株高度和分枝数,提高了马铃薯茎叶重量和花生的总果数、饱果数和饱果率,降低了秕果数,提高单株重量。施肥对作物产量和效益的影响是：甘薯,施肥〉不施肥,钾肥〉氮肥〉磷肥;花生,施肥〉不施肥,钾肥〉氮肥、磷肥;马铃薯,施肥〉不施肥,氮肥〉钾肥〉磷肥。同时,通过建立甘薯、花生、马铃薯在各种土壤类型上的产量和施肥利润与N、P、K三要素施用量的三元二次数学模型,获得作物适宜施肥量。甘薯,空白产量大于21000kg/hm^2,施肥预期最高产量32000kg/hm^2～42000kg/hm^2的中高产土壤的适宜施肥量为154.3～173.6kg/hm^2N,44.4～75.3kg/hm^2P2O5,193.1～245.3kg/hm^2K2O,N：P2O5：K2O=1：0.26～0.43：1.24～1.41;最佳经济施肥量为140.0～162.0kg/hm^2N,40.8～67.0kg/hm^2P2O5,199.9～227.3kg/hm^2K2O,N：P2O5：K2O=1：0.25～0.41：1.23～1.64;花生,适宜施肥量组合为112．7-123．8kg／hm^2N,41．2～64．0kg／hm^2P2O5,186．3-197．6kg／hm^2K2O,N：P2O5：K2O=1：0．37～0．52：1．56～1．69;最佳经济施肥量为74．5～87．7kg／hm^2N,32．0～68．5kg／hm^2P2O5,138．9-163．8kg／hm^2K2O,N：P2O5：K2O=1：0．43～0．85：1．80～2．04;马铃薯,适宜施肥量组合范围为168．2-247．5kg／hm^2N,55．0～88．0kg／hm^2P2O5,255．0～316．7kg／hm^2K2O,N：P2O5：K2O=1：0．22～O．48：1．28～1．53;最佳经济施肥量为168．2～233．2kg／hm^2N,61．4～81．4kg／hm^2P2O5 257．2-286．4kg／hm^2K2O,N：P2O5：K2O=1：0．26～0．48：1．23～1．61。     

龙花163花生新品种高产优化栽培模式研究

采用正交旋转设计,研究不同密度、穴播粒数、施肥方式对花生产量的影响,结果显示影响花生产量的栽培因子为密度〉施肥方式〉穴播粒数。龙花163的高产优化栽培模式为穴距15cm（即13．33万穴／hm^2）,一次性全层施肥（即N：P：K各含15％的复合肥750kg／hm^2）,穴播3粒。     

小麦花生两熟制一体化高产高效平衡施肥技术研究

将小麦花生两作视为一项整体工程,经研究建立了麦油两熟制一体化栽培平衡施肥决策系统。该系统充分考虑了土壤、作物产量、栽培措施等对肥料决策的影响,并通过气候、土壤及农业措施等对作物产量的综合影响,总结出确定适宜目标产量的方法,确保了系统决策结果的准确性和经济性。该系统用ＢＡＳＩＣ语言编制而成,用户可直接进行人机对话,操作简单,使用方便。山东、河南两省５ 县（市）４ 年（１９９５～１９９８）１７６个定点农户使用结果表明,小麦、花生分别平均增产９．１％ 和１２．５％     

云烟87肥料效应及平衡施肥技术初探

2007年在湖南未阳对烤烟实施“3414”肥效试验,结果表明：云烟87在平衡施肥条件下产量最高,减少和增加磷肥施用量对产量影响不显著,而减少和增加氮肥施用量对产量有显著影响,减少钾肥施用量减产极显著;建立了云烟87的施肥模型,其最佳经济施肥量为：N164kg／hm^2,P2O5 170kg／hm^2,K2O 408kg／hm^2。根据土壤速效养分的丰缺情况,制定了该品种的平衡施肥指标体系,对烤烟大田平衡施肥、节本增效具有一定的指导意义。     

花生高效施氮计算机专家决策系统

花生高效施氮专家决策系统是在课题组多年多点氮肥试验及根瘤固氮研究，且吸收了目前花生同领域的最新研究进展的基础上建立的。本系统在以下几个方面取得了较大进展。（1）该系统充分考虑了气候、土壤及农业措施等对作物产量的综合影响，总结出确定适宜目标产量的方法，使目标产量既能充分发挥土壤的增产潜力，实现作物的高产高效，又不至于因目...     

马铃薯优异种质GP2-12增施磷钾肥效果研究

在浙江省马铃薯主产区丽水市．通过2年试验研究了增施磷钾肥措施对优质马铃薯GP2-12的产量及相关生理性状的影响。试验表明．在当地习惯施肥基础上．同时增施磷钾肥,提高了马铃薯产量、块茎淀粉含量及商品率、叶面积系数、叶绿素含量和净同化率、同时表明．增施磷钾肥的不同处理效果不同．根据增产提质效果及实际效益．推荐施肥量为：N110kg／hm^2、P2O5 80kg／hm^2、K2O 180kg／hm^2、农家肥10^4kg/hm^2。     

优质小花生覆膜栽培播期与密度研究

大田试验结果表明，春播覆膜小花生鲁花12号的播期和密度产量效应显著，密度效应大于播期。因此，小花生要高产必须合理密植；当花生4月28日播种，密度为17．28万穴/hm^2时，英果产量最高，达4760．0kg／hm^2；在4月28日以前，花生播期每提前5d，英果产量平均减少203．9kg／hm^2，在4月28日以后，播期每推迟5d，英果产量平均减少260kg/hm^2；播期与密度表现为正向交互效应，在4月10日-5月20日范围内，花生播期每推迟5d，其最适密度应增加5540穴/hm^2。     

优质出口小花生高产生育规律及关键栽培技术研究

经过5年大田试验与培创高产田相结合，使鲁花12号、13号、青兰2号等优质小花生在较大面积上实现了6．0～6．75t／hm^2，明确了相应产量条件下生育规律，建立了一套以适时播种与最佳密度相结合、平衡施肥、加强叶部病害防治、“减量增次”缓控花生徒长为关键技术的优质小花生高产高效栽培技术规程。     

强筋冬小麦品种藁8901的优化施肥技术

通过对氮、磷、钾三因素旋转回归设计，以小麦产量和品质性状为目标，对强筋冬小麦品种藁8901的优化施肥技术方案进行了研究。结果表明，氮、磷、钾三因素对藁8901的产量和品质指标的影响各不相同。对产量和品质指标的作用大小顺序依次为氮〉磷〉钾，氮肥是影响该品种产量和品质指标的首要因素。通过藁8901产量和品质指标与氮、磷、钾三因素关系的回归方程进行多目标综合决策，模拟筛选出多个优化施肥量厦配合方案。入选方案的施肥量范围为N239．25～300kg／hm^2，P2O5 150～300kg／hm^2，K2O 112．5～225kg／hm^2。     

湖北潜江棉花"3414"施肥效果评价试验

通过在湖北潜江地区进行棉花施肥“3414”设计试验,探究湖北潜江地区棉花最禹施肥量与产量、最佳施肥量与产量的关系．避免盲目施肥,做到科学施肥,从而这到高产低耗、高效优质、持续环保的目的。通过试验得出以N2P2K2为湖北潜江地区棉花施肥最佳推荐配方。施肥方案为施纯氮315kg／hm^2、五氧化二磷54kg／hm^2、氧化钾135kg／hm^2。可以在该棉区推广应用。     

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.     

Studies on natural repellents against potato tuber moth (Phthorimaea operculella Zeller) in country stores

Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.     

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.     

In vitro antimicrobial activity of different accessions ofSolanum commersonii Dun. from Uruguay

Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.     

Extreme resistance to infection by potato virus X in genotypes of wild tuber-bearingSolanum species

Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta. Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X¹ (also called RX_act).     

Cyanobacteria Secondary Metabolites as Biotechnological Ingredients in Natural Anti-Aging Cosmetics: Potential to Overcome Hyperpigmentation,Loss of Skin Density and UV Radiation-Deleterious Effects

The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O₂^•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O₂^•− scavenging, (IC₅₀ = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC₂₅ = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC₅₀ = 863 µg/mL; elastase, IC₅₀ = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O₂^•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.     

Marine Pharmacology in 2009–2011: 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 peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.     

Recent Modifications of Chitosan for Adsorption Applications: A Critical and Systematic Review

Chitosan is considered to be one of the most promising and applicable materials in adsorption applications. The existence of amino and hydroxyl groups in its molecules contributes to many possible adsorption interactions between chitosan and pollutants (dyes, metals, ions, phenols, pharmaceuticals/drugs, pesticides, herbicides, etc.). These functional groups can help in establishing positions for modification. Based on the learning from previously published works in literature, researchers have achieved a modification of chitosan with a number of different functional groups. This work summarizes the published works of the last three years (2012–2014) regarding the modification reactions of chitosans (grafting, cross-linking, etc.) and their application to adsorption of different environmental pollutants (in liquid-phase).