豇豆不同类型间种子耐贮性差异

本文研究了不同类型豇豆种子经高温高湿（４０℃,１００％ＲＨ）老化处理后的发芽势,发芽率,发芽指数,活力指数和电导率的变化情况,结果表明,短荚豇豆亚种发芽各项指标下降率平均数以及相对电导率上升率平均数均比长荚豇豆亚种的低,因此,短荚豇豆亚种耐贮性比长荚豇豆亚种好。     

甲醇老化处理对玉米种子发芽和幼苗生长的影响

分析不同时间的50%甲醇老化处理对玉米种子发芽和幼苗生长的影响,明确甲醇老化处理的最佳时间。结果表明,与蒸馏水浸泡40 min(CK)相比,50%甲醇老化处理10~30 min时种子发芽指标(活力指数除外)均无显著变化;40 min时种子发芽率、发芽势、发芽指数、活力指数分别降低5.67%、8.67%、11.08%和41.22%;50 min时分别降低6.00%、10.00%、18.05%和47.70%;60 min时分别降低21.33%、28.00%、35.62%和61.80%;70 min时种子发芽指标降至较低水平。甲醇老化处理10 min时,玉米幼苗苗高、根长、根苗比、苗重和根重均显著降低,且降低幅度高于发芽指标。与CK相比,甲醇老化处理10~30 min时对种子脱氢酶活性和相对电导率无显著影响,40~70 min时脱氢酶活性显著降低,相对电导率显著增加。因此,50%甲醇老化处理应选择40~60 min为宜。     

新疆春小麦品种种子耐老化评价

为筛选出耐老化春小麦品种,采用高温高湿(41℃,95%RH)人工老化法对33份新疆春小麦品种进行种子老化处理,分析了老化对春小麦种子发芽势、发芽率、发芽指数及活力指数的影响,以耐老化系数为基础,运用加权隶属函数和聚类分析法对参试品种的种子耐老化性进行了综合评价及分类。结果表明,品种间种子耐老化能力差异显著。与对照相比,种子发芽势和发芽率分别下降41.16和30.96个百分点,发芽指数和活力指数分别降低50.29%和64.77%,差异均达极显著水平。通过加权隶属函数和聚类分析,将33份材料划分为4种耐老化类型,其中新春6号、新春30号、新春40号、新春41号、新春43号、新春47号等6份品种种子耐老化能力突出,可以作为小麦耐老化育种的亲本。     

抗低温处理对玉米种子萌发特性的影响

用SA、SG、SN、NG4种处理荆处理玉米种子．在不同程度低温条件下培养．研究抗低温处理后的玉米种子萌发的变化和差异。结果表明,各处理的发芽势、发芽率、发芽指数和活力指数等指标在低温条件下较对照（蒸馏水浸种）都有不同程度的提高。在10～16℃条件下。SG和NG处理可以大幅度提高玉米种子的萌发指标．其中对发芽率的影响最为明显．提高幅度最高达1．58倍,达极显著水平。认为．SG和NG处理可以提高玉米对低温的忍耐力．具有促使玉米种子在低温条件下早生快发的作用。     

糯玉米种子老化过程中种子活力和生理特性的变化

以京科糯2000和莱农糯6号玉米品种为试验材料,采用老化箱人工老化法,研究人工老化对糯玉米种子发芽指标和生理特性的影响。结果表明,随老化时间的延长,两个糯玉米品种种子的发芽势、发芽率、发芽指数、活力指数和脱氢酶活性逐渐降低,丙二醛(MDA)含量和相对电导率逐渐升高。老化14 d时,京科糯2000和莱农糯6号种子的发芽势、发芽率、发芽指数和活力指数分别比对照降低48.31%和42.86%、41.05%和31.31%、52.86%和42.64%、68.84%和56.43%,脱氢酶活性分别降低70.18%和45.48%,MDA含量分别增加54.04%和49.41%。相关分析表明,两个糯玉米品种的种子活力与MDA含量和脱氢酶活性之间均达极显著相关,MDA含量和脱氢酶活性可以表征糯玉米种子的老化程度。种子耐老化能力存在品种间差异,莱农糯6号耐老化能力高于京科糯2000。     

宁夏春小麦品种资源种子耐老化性综合评价

为筛选出耐老化小麦品种,采用高温高湿（41 ℃,95% RH）人工老化法对64份宁夏引黄灌区春小麦品种资源进行老化处理,测定老化前后种子的发芽势、发芽率、发芽指数、活力指数、种子蛋白质含量及湿面筋含量,根据各指标的耐老化系数,运用主成分分析、隶属函数和聚类分析法对参试材料的耐老化性进行综合评价。结果表明,老化后种子的发芽势、发芽率、发芽指数、活力指数和湿面筋含量显著降低,而蛋白质含量无明显变化。通过主成分分析将6个单项指标转换为3个相互独立的综合指标,其贡献率分别为59.760%、18.160%和15.260%,代表了全部数据93.190%的信息量。运用隶属函数法计算综合耐老化值（D值）,并对其进行聚类分析,按照耐老化性强弱,将64份材料划分为3类。第一类高耐老化型材料10份;第二类普通耐老化型材料37份;第三类老化敏感型材料17份。宁春4号、宁春10号、宁春11号、宁春20号、宁春26号、宁春29号、宁春34号、宁春43号、宁春53号、宁春68号为耐老化品种。     

玉米种子耐储性的全基因组关联分析及候选基因预测

以197份玉米自交系为试材,人工加速老化后进行标准发芽试验,检测种子耐储性相关表型性状,结合平均分布于玉米基因组的SNP标记进行关联分析,挖掘关联SNP位点和候选基因。结果表明,共检测出8个与相对发芽势（RGE）、相对发芽指数（RGI）、相对活力指数（RVI）和相对简易活力指数（RSVI）等性状呈显著关联的SNP位点（P<0.000 1）,分布于染色体bin1.08、bin3.08、bin4.03、bin4.05和bin6.05区域;PZE-104063000、PZE-104064763和PZE-106085414这3个SNP位点均与2个性状关联。预测到7个候选基因,分别与纤维素合成酶活性、翻译起始因子、丝氨酸/苏氨酸蛋白激酶活性、磷酸二酯酶活性、类囊体膜组分、脂肪酸生物合成酰基转运活性和微管有关组分等相关。     

60份玉米自交系种子的耐老化鉴定

选用60份玉米自交系为试验材料,通过室内高温高湿法鉴定并分析种子耐老化特性。结果表明,不同基因型玉米自交系种子在老化胁迫后,其发芽势和发芽率性状差异显著,平均值分别为10.93%和35.12%,比对照分别降低了88.0%和64.9%,相对发芽势变异幅度0～80.41%,平均为12.18%;相对发芽率变异幅度0～99%,平均为35.12%。综合发芽性状指标、方差分析和聚类分析结果,筛选出FK1239、加早19、加早32、PHRE1、加早62、吉A1035、R5117、丹598等8份耐老化玉米自交系。     

13份玉米自交系品质性状及种子活力的配合力分析

采用NCII设计(6×7)组配42份杂交组合,采用随机区组试验,测定杂交组合的品质性状和种子活力指标,分析自交系性状配合力、遗传参数、相关系数。结果表明,组合活力指数的变异系数较大,其他性状均较小。品质性状一般配合力分析,5003改良系、Mo17变异株较优良。活力指标一般配合力分析,5003改良系、78599较优良,发芽率、发芽势、发芽指数、活力指数、脂肪、淀粉、蛋白质的广义遗传力和狭义遗传力均大于50%。除发芽率与发芽势、活力指数相关系数外,42份杂交组合的发芽率、发芽势、发芽指数、活力指数的相关系数均呈显著或极显著正相关。淀粉含量与活力指数、脂肪含量呈显著负相关;淀粉和蛋白质含量呈负相关,但未达到显著水平。     

NaCl胁迫对玉米自交系种子萌发的影响

以不同玉米自交系为筛选材料,进行种子萌发期耐盐胁迫筛选研究。通过对发芽率、相对发芽率、耐性分布频度、萌发进程、相对发芽指数等指标的分析,将玉米自交系的耐盐能力划分为5个等级。极耐盐的自交系哲446、通81-248、九51、引玉2号,较不耐盐的自交系A638、司徒、1261、C91-11。     

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.     

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.     

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.     

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.     

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).     

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).     

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.