高赖氨酸玉米亲本间遗传距离与杂种优势和配合力的关系

本文以8个高赖氨酸玉米自交系以及这8个亲本的56个完全双列杂交组合为材料,考查产量、品质等14个性状,进行遗传距离分析.结果表明,赖氨酸产量、蛋白质产量、脂肪产量和籽粒产量这4种产量性状的遗传距离与超亲优势、超标优势和特殊配合力之间都不存在显著的相关关系.但有一种趋势,即杂种优势较大的组合大多有较大的遗传距离.亲本的平均遗传距离与一般配合力之间也不存在显著的相关关系.遗传距离分析结果还属于参考性的,在实际育种工作中,进行配合力的测定依然是必要的.     

玉米营养品质的遗传研究与育种进展

概述了我国玉米子粒营养品质的现状,对主要营养品质性状蛋白质、脂肪和淀粉含量及组成的遗传及其与产量之间的相关性、分子标记与基因定位以及营养品质育种的研究进展进行了综述.并提出了国内玉米营养品质研究存在的问题与对策。     

玉米品质性状配合力研究

以分属四大杂种优势群的8个典型玉米自交系及其组配的28个双列杂交组合(不含反交)为试材,对玉米自交系及杂交一代产量与品质性状的遗传特性进行了研究,结果表明:脂肪含量、淀粉含量主要受基因加性效应影响;而蛋白质含量受基因加性效应和非加性效应共同影响.对于主要受加性效应影响的性状表现一般配合力高,则特殊配合力也高的趋势;对于既受加性效应影响又受一定非加性效应影响的性状,一般配合力影响特殊配合力,实际杂交组合的表现受二者共同影响.     

杂交稻主要农艺性状的配合力和遗传力分析

利用4个不育系与3个恢复系按不完全双列杂交配制的12个组合及其亲本材料,统计分析了7个农艺性状的配合力、配合力总效应值与其实际值的相关和回归关系,以及群体配合力方差和遣传力。结果表明:绝大多数恢复系农艺性状的一般配合力作用大于不育系的一般配合力作用;一般配合力和特殊配合力在性状的表现中处于同等重要的作用;在产量上,一般配合力最高的不育系地谷A与一般配合力最高的恢复系测64所配制的地优64杂种,其特殊配合力也是最高的;绝大多数农艺性状的配合力总效应值与其实际值存在密切相关,可以用配合力总效应值估计杂交稻产量的高低。     

粳稻不同生态类型间F1的杂种优势及其亲本的配合力分析

用8个不同生态类型的粳稻品种配成8×8双列杂交,研究8个重要农艺性状的杂种优势以及亲本的配合力。结果表明,不同生态类型间杂种F1 各性状的优势有正有负。56个F1组合平均, 小区产量性状表现19.5%的高亲优势, F1小区产量超过高亲值的组合占87.5%,其余7个性状的F1值位于中亲值与高亲值之间。 在不同生态类型所构成的总体中,株高、每穗总粒数、每穗实粒数和小区产量4个性状的加性遗传方差和非加性遗传方差同等重要;抽穗期、穗长、单株有效穗3个性状的加性遗传方差更重要;千粒重性状非加性遗传方差更为重要。小区产量和产量构成因素一般配合力效应和特殊配合力效应方差较大的亲本是秀水04和3726;特殊配合力效应大且综合性状优良的组合是越光/秀水04。     

大豆品种表现型与配合力的相关分析

大豆植株的表现型与配合力的相互关系分析结果表明，植株形态性状的亲本均值与Ｆ１、Ｆ２的一般配合力效应值里呈著或极显著正相关。Ｆ１、Ｆ２的主要产量性状的均值与相应世代的特殊配合力效应值呈显著或极显著正相关。植株形态性状和品质性状的Ｆ１育种值与Ｆ２均值呈显著或极显著正相关。植株形态性状、产量性状及品质性状总配合力效应值世代间相关显著。     

小麦沉淀值的研究进展

沉淀值是评价小麦面筋强度和烘烤品质的重要指标。本文综述了沉淀值在小麦不同品种间的变异、遗传力、杂种优势和配合力方面的研究概况;分析了沉淀值与重要农艺性状（抽穗期、株高、产量因素等）、品质性状和ＨＭＷ麦谷蛋白亚基组成的相关关系,认为沉淀值作为早代选择指标,既简便有效,又有利于协调产量与品质以及品质性状之间的关系。     

新疆哈克尼西棉新不育系和恢复系主要性状配合力分析

本文采用7×3不完全双列杂交分析法,对新转育的哈克尼西棉不育系、恢复系的纤维品质性状和产量配合力及遗传力进行分析。结果表明：籽棉产量、断裂比强度主要受加性效应影响,铃重主要受非加性效应影响,衣分、皮棉产量、纤维上半部平均长度、整齐度、马克隆值、伸长率、黄度受加性和非加性效应共同影响,以加性效应为主;籽棉产量、皮棉产量、纤维上半部平均长度、断裂比强度、整齐度、马克隆值、伸长率、黄度中母本基因型贡献率高。不育系选育应从提高衣分、品质性状着手合理配组,实现育种目标。亲本A1、R3的多数性状一般配合力效应高,A1×R3的组配品质性状特殊配合力效应较好,产量性状表现突出。     

杂交大豆配合力及杂种优势分析

为了提高杂交大豆育种效率,进一步提高杂交大豆产量。本研究以5份大豆细胞质雄性不育系为母本,12份恢复系为父本,采用NCⅡ设计方法组配60个杂交组合,对产量、单株荚数、单株粒数和每荚粒数分别进行杂种优势、配合力效应、及其与F1性状的相关性分析。结果表明,F1产量性状中亲优势组合占全部组合的55%,超高亲优势组合占30%,中亲和超高亲优势均?20%的占15%。单株荚数、单株粒数、每荚粒数等产量相关性状的中亲优势组合分别占55%、56.67%和23.33%,超高亲优势率均为负值。17份亲本材料的一般配合力（general combining ability,GCA）变化范围为-27.94%～56.62%,其中6份材料表现为正效应;30个杂交组合的特殊配合力（special combining ability,SCA）为正值,占总体的50%。此外,SCA与F1籽粒产量和单株荚数的杂种优势及其性状值均相关;GCA与产量性状值和单株粒数的中亲优势呈极显著相关,与单株荚数的中亲优势、单株粒数、每荚粒数的超高亲优势及性状值呈显著相关;各性状SCA与GCA之间不相关。单株荚数和单株粒数对产量的贡献较大。产量杂种优势强的组合双亲除具有高的一般配合力,而且兼具有较高的特殊配合力。     

几个小麦品种品质性状遗传特性分析

为了解小麦品质性状的遗传特性,指导小麦优质育种的亲本配组,选择8个品种和2个新品系,采用不完全双列杂交,配置25个杂交组合,对F_1代产量、千粒质量、湿面筋含量、蛋白质含量、面筋指数、稳定时间等性状进行方差分析和杂种优势分析、一般配合力(GCA)和特殊配合力(SCA)进行相关性分析。结果表明,产量杂种优势整体表现为负向优势,千粒质量为正向优势,其它品质性状整体表现为正向优势;4个亲本材料新麦26、洛麦47、藁优5766及洛麦41的多个品质性状GCA值均较好,可作为综合性状优良的优质亲本;丰德存麦13在产量性状上GCA值最大,适合作为产量改良亲本使用;组合洛麦47×丰德存麦13、洛麦47×丰德存麦5号、郑麦366×藁优5766多个性状SCA效应值和杂种优势值均较高,可作为重点组合进行后代筛选;相关性分析表明,F_1各性状均值与亲本一般配合力之和(GCAs)均呈极显著相关,产量、千粒质量、湿面筋、蛋白含量的F_1值也与杂种优势值和SCA值紧密相关,沉降值、吸水率、面筋指数和稳定时间的F_1值受组合影响较小,主要与双亲的GCAs值相关。     

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).