广西山圩农场剑麻园土壤养分状况研究

为了解广西山圩农场剑麻园土壤养分状况,采用常规方法,分析测定4个分场195个土壤样品。结果表明,土壤pH为4.78～8.21,平均为6.51,以中性土、弱酸性土为主,分别占47.7%、32.8%;有机质含量为14.74～45.33 g/kg,平均为25.61 g/kg,其中63.6%土壤样品处于中等水平;全氮含量为0.70～2.08 g/kg,平均为1.19 g/kg,处于中等偏低水平;土壤有效磷含量在2.348～77.524 mg/kg,变化幅度较大,平均为20.432 mg/kg,总体处于中等和中上水平;速效钾含量为25.882～681.619 mg/kg,平均为115.449 mg/kg,变化幅度较大,总体处于中等偏低水平。     

不同硒源对芝麻富硒效应的影响

芝麻品种豫芝10号施用不同含硒量的硒矿粉、富硒复混肥(含硒复混肥)、亚硒酸钠(Na2SeO3)溶液试验结果表明:①不同形态的硒源均能提高芝麻的含硒量,施入3种不同形态硒源的芝麻植株含硒量为0.216mg/kg～0.614mg/kg,比对照的0.108mg/kg高120.65%～456.11%,平均提高了277.5%;②芝麻不同部位的富硒效果不同,籽粒＞荚＞叶＞根,生殖器官优于营养器官;③营养器官中较成熟的叶片含硒量大于较幼嫩的叶片,说明芝麻的富硒存在着一个积累的过程;④在当季的芝麻栽培中,施用Na2SeO3的芝麻籽粒中含硒量平均为1.1185mg/kg,富硒复混肥处理平均为0.6545mg/kg,富硒矿粉处理为0.4390mg/kg,比对照(0.1640mg/kg)增加167.7%～ 582.0%,平均增加345.9%.3种硒源的当季效果依次为Na2SeO3＞富硒复混肥＞富硒矿粉;⑤用Na2SeO3溶液根外追施,其适宜、经济有效的浓度为50mg/kg～100mg/kg,超过350mg/kg时,芝麻叶片灼伤严重,籽粒含硒量降低.     

海南甘蔗土壤养分状况研究

通过对海南西部儋州、昌江、白沙,北部临高、澄迈和定安,主要甘蔗产区0～20cm土层共85个样品进行分析。结果表明,海南蔗区土壤pH值平均为4.50,88.23%的样品pH值5.5;土壤有机质含量平均为15.3g/kg,38.82%的样品有机质含量小于10g/kg;62.35%的样品碱解氮含量低于60mg/kg;38.82%的样品有效磷含量小于10mg/kg;78.82%的样品速效钾含量小于50mg/kg;60.0%的样品交换性钙含量小于450mg/kg;80.0%的样品交换性镁含量小于120mg/kg;28.24%的样品有效硫含量小于12mg/kg;83.53%的样品有效硼含量低于临界值;蔗区土壤有效锌含量和有效铁含量较为丰富。     

我国部分大米含硒量分析及生物硒肥对籽粒硒水平的影响

用原子荧光分光光度法测定了江苏省 5 2个不同品种大米样品、全国部分省市 30个大米样品以及两种用不同硒生物肥生产的富硒大米的含硒量 ,研究了生物硒肥对大米含硒量及硒形态的影响。结果表明 ,江苏省的大米含硒量为 0 .0 15～ 0 .0 5 6 mg/kg,平均为 0 .0 35 mg/kg± 0 .0 0 9mg/kg;全国部分地区的大米含硒量为 0 .0 11～ 0 .0 5 5 mg/kg,平均为 0 .0 2 5mg/kg± 0 .0 11mg/kg,湖北恩施的大米含硒量达 0 .2 6 2 mg/kg。依据中国营养学会推荐的谷物食品摄入量 ,推算江苏省和其他地区居民从大米中摄入的硒分别为 10 .5～ 17.5 μg/(d·人 )和 7.5～ 12 .5 μg/(d·人 )。在水稻齐穗期喷施硒 2 0 g/hm2 ,大米含硒量由普通大米的 0 .0 71mg/kg分别提高到 0 .4 71mg/kg和 0 .6 4 0 mg/kg,有机硒比例分别由普通大米的 78.38%提高到 87.11%和 89.0 8%。外源硒能显著提高大米的含硒量和有机硒含量及比例     

黄精栽培地土壤养分与药材质量评价研究

目的分析黄精栽培基地土壤养分分布规律,评价药材内在质量,为栽培生产优质高产黄精药材提供数据支撑和理论依据。方法采集黄精栽培地土壤与黄精药材各14份,用土壤养分速测仪测定土壤pH、有机质、碱解氮、速效磷、速效钾各项指标;用苯酚-蒽酮法测定黄精药材内多糖的含量。结果黄精栽培地土壤pH、有机质、碱解氮、速效钾、速效磷变化范围分别是6.75～8.50,6.52～18.77g/kg,8.08～69.80mg/kg,21.79～116.41mg/kg,41.09～201.47mg/kg,平均值分别为7.35、11.04g/kg、32.36mg/kg、63.53mg/kg、98.47mg/kg;黄精药材含量为6.13～12.17%,平均含量为9.09%。结论根据全国土壤分级标准,柳河县黄精种植地土壤养分状况总体表现为土壤呈中性,有机质、速效钾含量中等,速效磷含量极丰富,碱解氮含量明显缺乏,黄精多糖含量符合药典规定。吉林省柳河县适宜栽培黄精药材,但在栽培过程中应及时补充氮肥和钾肥。     

气相色谱法测定香蕉和土壤中苯醚甲环唑残留

建立气相色谱法测定香蕉和土壤中苯醚甲环唑残留量的分析方法。样品经乙腈萃取，采用气相色谱法-氮磷检测器(GC-NPD)进行测定。方法的检出限为0.010 mg/kg，在0.02、0.20、1.00 mg/kg 3个添加水平，香蕉回收率为82%～105%，相对标准偏差为7.4%～10.7%；土壤回收率为80%～104%，相对标准偏差为5.1%～9.3%。方法的重复性较好。     

超高效液相色谱-串联质谱法测定甜菜中甜菜安和甜菜宁的残留量

建立了同时测定甜菜安和甜菜宁在甜菜中残留量的分析方法。样品用乙腈和水混合振荡提取,盐析后取有机相浓缩,浓缩液经PSA分散固相萃取净化,超高效液相色谱-串联质谱测定。测定结果,甜菜安在甜菜中的平均回收率为91.1%～95.6%,相对标准偏差为2.4%～7.6%;甜菜宁在甜菜中的平均回收率为93.4%～95.8%,相对标准偏差为5.0%～9.8%。甜菜安及甜菜宁在甜菜中的定量限(LOQ)均为0.02 mg/kg;甜菜安的检出限(LOD)为1.5×10-3 mg/kg,甜菜宁的检出限为2.6×10-4 mg/kg。田间试验表明:甜菜苗期施药,收获期甜菜中的甜菜安及甜菜宁残留量均低于0.02 mg/kg。     

液相色谱法测定香蕉中赤霉素残留

建立香蕉中赤霉素残留量的测定方法。样品经甲醇提取，使用石油醚进行脱色，经C18固相萃取小柱净化后，使用高效液相色谱法(紫外检测器)进行测定。方法检出限为0.1 mg/kg，在0.50～10.0 mg/kg添加水平，回收率为86% ～105%，相对标准偏差为2.0%～4.8%。     

陕西关中灌区冬小麦土壤养分丰缺指标体系的建立

为给陕西关中地区小麦合理施肥提供科学依据,2006-2008年在陕西关中灌区进行了多点冬小麦"3414"田间试验,分析了不同土壤肥力水平下冬小麦土壤有效养分含量与相对产量的相关性,并依此确定土壤养分等级和推荐施肥量.结果表明,关中灌区小麦田土壤碱解氮含量等级可划分为低(<60 mg/kg)、中(60～100 mg/kg)、高(100～120 mg/kg)和极高(>120 mg/kg);速效磷含量可划分为低(<10 mg/kg)、中(10～30 mg/kg)、高(30～45 mg/kg)和极高(>45 mg/kg);速效钾含量分为高(100～165 mg/kg)和极高(>165 mg/kg).当土壤碱解氮含量处于低、中、高等级时,氮肥推荐用量分别为155～175、135～155、125～135 kg/ha,极高等级的推荐施氮量未能确定;当土壤速效磷含量处于低、中、高和极高等级时,磷肥(P2O5)推荐用量分别为120～140、90～115、70～90和60～70 kg/ha;当土壤速效钾含量处于高和极高时,钾肥(K2O)推荐用量为50～80和15～35 kg/ha.     

稻谷对铅富集特性的品种差异及其安全风险

以漳州当地15个水稻主栽品种为试材,采用添加铅源的盆栽试验及大田试验,考察稻谷对铅富集特性的品种差异及评价其质量安全风险。结果表明,在弱酸性（5.5相似文献   

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.     

Mineral composition of some traditional Mexican teas

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.     

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.