大杯香菇辐射选育新株系品质性状的遗传分析

以20个大杯香菇品种和辐射选育新株系为材料,对22个品质性状其进行了相关和主成分分析。结果表明,遗传变异系数最大的品质性状为SOD活性(47.16%),其次为胱氨酸含量(44.33%),再次为MDA含量(44.12%),第四为PPO活性(43.89%),变异系数最小为缬草氨酸含量(4.89%);子实体中的各种氨基酸含量、可溶性蛋白含量、细胞保护酶活性和MDA含量之间均存在一定的相关性,部分性状间相关性达显著至极显著。主成分分析结果表明,22个性状可以缩减为7个主成分,遗传变异贡献率大小分别为37.82%、18.07%、13.14%、9.80%、6.02%、4.94%和2.67%,7个主成分累积贡献率达92.47%。由此可见,在品质性状选择上,首先对遗传变异大的性状进行选择是非常重要的。在品种和辐射选育新株系选择时,应注意选择甲硫氨酸含量、可溶性蛋白含量和CAT活性较高的品种,这样才能比较容易获得综合品质性状优良的新品种。     

甜菜块根农艺性状的遗传变异及相关性和主成分分析

以25个新疆甜菜品系(种)为材料,对块根8个主要农艺性状进行变异系数、相关性和主成分分析。结果表明:根头长度的变异系数较大为29.14%,根宽的变异系数最小为7.86%。在相关性上,糖甜菜根宽、根颈周长、根头长与根重呈极显著正相关;甜菜含糖率与根体长度呈极显著的正相关。主成分分析结果表明,前3个主成分对含糖率变异的累计贡献率达到85.21%,对根重变异的累计贡献率达到88.53%。首先对变异大的性状进行选择是非常重要的,在含糖率性状选择上,应注意选择根颈长度、根颈周长、根体长度大,根沟较深的品系(种)。在根重性状选择上,应注意选择根宽、根颈周长、根颈长度大,根沟较浅的品系(种)。     

辣椒花器性状的遗传分析

估算辣椒(Capsicum annuum L.)花器性状的遗传变异系数和遗传力,结果表明,柱头外露长、柱头宽和花宽的遗传变异系数较大,花宽、花长/花宽、花药长和柱头宽的遗传力较大,且遗传型变异系数较大的性状,它的遗传力不一定大。相关和通径分析结果表明,辣椒柱头外露长与花长、柱头长和花长/花宽间的遗传相关达显著或极显著水平,大多数情况下都是遗传型相关系数绝对值大于表型相关系数绝对值,花宽和花长/花宽对柱头外露长的直接作用较大。估算26个辣椒品种、9个花器性状的主成分值,并将其分为6类,数量分类的结果符合实际情况。当主成分的特征值的累计贡献率接近85%时,主成分值就能基本反映花器性状的遗传特征。比较不同的系统聚类方法,离差平方和法较好地适合用于辣椒品种花器性状的数量分类。     

中国花生核心种质的主成分分析及相关分析

以576份中国花生全套核心种质为材料,对26个表型性状方面进行主成分和相关性分析。结果表明,花生资源在这26个性状方面均存在显著的遗传分化和丰富的多样性。从主成分分析的结果来看,前5个主成分对变异的累积贡献率达72.67%,叶片宽、种子宽、百果重和百果仁重对花生种质资源主成分1 贡献较大,表明在花生种质资源鉴定中,这些性状占有重要地位。相关性分析结果表明,主茎高和主茎节密度呈显著负相关,主茎高和主茎节数,叶片长与叶片宽,荚果宽与种子长、种子宽、百果重、百果仁重等呈显著正相关。这些相关性表明,测得相关性极显著的一对表型性状中的一个即可判断另一个性状的变异状况,减少了花生种质资源鉴定的工作量。     

45个莲瓣兰品种的表型多样性研究

收集45个莲瓣兰（Cymbidium tortisepalum）主栽品种,对29个表型性状进行数据收集。计算性状变异系数,进行主成分分析、相关性分析及聚类分析探究莲瓣兰品种间亲缘关系及遗传差异大小。结果表明：45份材料各性状的变异幅度为10.1%~133.1%,具有丰富的遗传差异;主成分分析结果表明共得到7个特征值大于1的主要成分,累积方差贡献率高达75.461%,其中第一和第二主成分主要代表了花部综合性状;相关性分析结果表明大部分性状都具有相关关系,其中93对性状显著相关,65对性状极显著相关;聚类分析结果表明在欧式遗传距离15时可将45份莲瓣兰分为3个类群。     

椰枣F1分离群体表型多样性的分析与评价

为了解椰枣F₁分离群体的表型性状的多样性，本研究以143份椰枣F₁分离群体为供试材料，对其株高、冠幅、茎围、枝条数和叶斑病发病情况等17个表型性状进行多样性、相关性、主成分及聚类分析。结果表明：椰枣F₁分离群体表型变异程度高，具有丰富的多样性。数量性状变异程度较高，变异系数为10.927%～43.350%，其中茎围的变异系数最大。质量性状变异系数为31.447%～44.619%，其中裂叶叶色和裂叶坚硬程度的变异系数分别为44.619%和42.571%。相关性分析表明：株高、冠幅、茎围、枝条数、第三枝长、刺区长度、裂叶总数、裂叶长、裂叶宽、裂叶厚度、裂叶叶色11个性状两两间均达到极显著正相关；叶斑病发病情况与其余16个性状均呈负相关。主成分分析显示，6个主成分的累计贡献率达87.51%，其中第1主成分特征值为10.0836，贡献率为59.32%，主要包含株高、第三枝长、冠幅、茎围和枝条数这5个指标共同影响，其中株高的特征值最大为0.2948，主要反映的了椰枣株高和长势情况。聚类分析表明：143份椰枣F₁     

膜下滴灌栽培水稻品种农艺性状相关性与主成分分析

在膜下滴灌旱作栽培技术条件下,对12个水稻品种主要农艺性状进行主成分分析。结果表明,水稻品种各农艺性状的变异系数存在较大的差异性,其中结实率的变异系数最小,为1.99%;穗粒数的变异系数最大,为14.22%;产量的变异潜能较高。相关性分析显示,株高与穗长呈正相关,穗粒数与产量呈正相关。主成份分析表明,4个主成分累计贡献率为84.33%。     

43份割手密资源农艺性状遗传多样性评价

为揭示割手密种质资源的遗传多样性,对野外采集的43份材料的株高、叶长、叶宽、茎径、节数等15个重要农艺性状进行检测和分析。结果表明,参试材料在这15个性状上都表现出较大的遗传变异,变异系数在9.87%~206.37%之间。主成分分析显示7个主成分对变异的累计贡献率达86.66%,可作材料选择的重要依据。聚类分析将参试材料分为3类,其遗传关系与地理来源没有必然联系。     

基于主成分和聚类分析的冀花高油酸花生品种综合评价

利用3年表型和重测序数据分别对11个冀花高油酸花生品种进行主成分分析和聚类分析。结果发现,15个性状中脂肪含量变异系数最小为1.91%,除亚油酸外产量性状变异均大于品质变异系数,百果重与百仁重呈极显著正相关,油酸和亚油酸呈极显著负相关。主成分分析提取的前2个主成分累计贡献率达78.99%,利用表型性状对品种进行分类,结果与系谱关系部分一致。质控后获得320 000个分布均匀的高质量SNP位点,利用基因型数据将11个品种聚为4类,能够将同一组合衍生品种划分为同一类,结果与品种系谱关系一致。因此,利用基因型数据更能准确反映品种内在遗传基础,为种质资源的分类和利用提供参考。     

不同地理种源麻疯树植物学形态变异研究

针对不同地理种源麻疯树植物学形态变异特征规律,用主成分分析、聚类分析等方法,对60份不同来源地麻疯树的22个数量性状指标进行分析。结果表明,不同地理种源麻疯树在种植3 a的植株主干高度变异范围最大(3.0~37.3 cm),变异系数为55.03%,其次是叶厚、花序柄长、雌雄开花比例、结果数、二级分枝数和雌花数,变异系数都大于27%,变异幅度最小的为果横径(2.02~3.07 cm),变异系数为7.21%;主成分分析结果显示,前7个主成分的累计贡献率为73.77%,其中第1主成分主要由冠幅(东西、南北)、叶宽、叶长、植株高度、叶柄长5个数量性状构成,第2主成分主要由雌花数、雄花数、结果数、花序长4个数量性状构成,第3主成分主要由种子横径、种子纵径、花序柄长3个数量性状构成,第4主成分主要由果横径和果纵径构成,第5主成分主要由一级分枝数和二级分枝数构成,第6主成分主要由雌雄开花比例构成,第7主成分主要由主干高度构成,方差贡献率依次为24.35%、13.89%、9.73%、8.52%、7.52%、5.02%、4.73%;以此19个数量性状为基础的聚类分析将60份麻疯树种质分为6类。     

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.