大麦开颖性状的遗传分析Ⅲ.大麦开颖基因的等位性及非等位基因间的互作

为了探讨大麦开颖基因数、基因之间的等位性以及非等位基因间的互作,以闭颖亲本91单2与4个开颖亲本(沪1154、1430R、99-7122、扬0187)的杂种F2群体、回交BC1、BC2群体及4个开颖品种(系)互交杂种F2群体为材料,于2004年大麦开花期测量各群体内植株的开颖角度,统计分析各群体内开、闭颖植株的分离情况.结果表明:(1)沪1154、1430R、扬0187的开颖角度分别由1对、2对和3对基因控制,扬0187基因间的互作为重叠作用;99-7122遗传比较复杂,可能有2对或3对基因控制;(2)扬0187与沪1154有一对开颖等位基因,且此基因的效应较大;1430R和99-7122与其他2个开颖亲本均存在各自的非等位基因;(3)开颖性状均是由主基因控制的,同时存在多基因的修饰,闭颖表现为显性.     

两系杂交小麦杂种优势、配合力及遗传距离分析

通过对15个亲本及其不完全双列杂交组配的56个杂种F_1的5个性状进行杂种优势、配合力与遗传距离分析,以研究两系杂交小麦强优势组合的选配规律及其亲本的利用价值。结果表明:(1)5个性状均表现正向中亲优势,其大小顺序为:株粒重>穗粒数>株穗数>千粒重>株高,其中株粒重、穗粒数、株穗数的超高亲优势和超对照优势均为正值;(2)强优势组合的产生是产量构成因素优势相互补充与积累的结果;(3)根据遗传距离的大小,15个亲本可划分为五大类群,不育系与恢复系完全划分为不同的类群;(4)在亲本选配上,选择一般配合力和特殊配合力效应方差综合表现较好、遗传距离中等者为佳。     

籼型杂交水稻杂种与亲本的稻米品质比较

 以具广泛代表性的7个不育系和9个恢复系及其配制的63个组合为材料,对籼型杂交水稻11个稻米品质性状的杂种与亲本的表现进行了比较研究。就全部杂交组合各品质性状相对优势而言，无论是超亲优势、完全显性还是部分显性，都表现为负向的几率远大于正向。 组合间杂种品质表现的差异因性状而异,无论是中亲优势指数、超高亲优势指数，还是超低亲优势指数，均以垩白大小、垩白粒率、胶稠度和整精米率等性状组合间变异为大。全部性状杂种平均值都显著或极显著低于高亲值。除精米长和直链淀粉含量杂种值极显著高于中亲值外，其余性状都与中亲值接近或极显著低于中亲值。除糙米率、精米率和胶稠度杂种值低于低亲值外，其余性状都显著或极显著高于低亲值。     

两个中籼水稻品种的抽穗期遗传

南京11和武进香籼均为中籼稻品种,F₁生育期超(晚)亲优势极强。通过对F₁、F₂、BC₁、BC₂等世代在自然日长或短日照处理条件下抽穗期的考察,证明杂种超亲迟熟与双亲的3个感光性主基因位点的分化有关,三者以互补方式决定植株的强感光性;两亲本分别含有2对和1对互补基因,根据系谱分析双亲的互补基因分别来自我国华南或东南亚的水稻品种。     

杂交大麦主要农艺性状及产量性状中亲优势的分析研究

通过对12个大麦杂种组合F19个性状中亲优势的研究分析，结果表明：杂种F1在株高、穗长、千粒重、穗下节长均表现为一致的正向中亲优势；着粒密度表现出一致的中亲负向优势；其余各研究性状的中亲优势在不同的组合表现不同；明确了应选用平均株高适中的两亲本配制杂种；并可通过F1穗下节长来选择单株粒重较高的组合。     

不同类型水稻亲本的抽穗期遗传关系研究

选用5个籼稻、2个粳稻和1个爪畦稻共8个亲本按半双列杂交配制28个组合．研究分析了亲本及组合抽穗期的特性及遗传关系,发现抽穗期的主要表现可归纳为三种类型：明显的显性早熟、部分迟熟显性和超显性迟熟,这些遗传表现可能分别是显性早熟基因、迟熟基因和不等位的抽穗期迟熟基因或感光基因互作而引起的。在杂交稻育种上,通过选择适宜亲本不仅可以培育早熟杂交稻组合,而且可以避免杂交稻组合抽穗期超亲问题,特别是籼粳亚种间组合抽穗期超亲问题。     

不同遗传背景马铃薯杂种群体生产力和一致性评价

本试验研究了具不同血缘和基因频率的马铃薯杂种群体的主要经济性状表现和一致性的差异,结果表明: 1.马铃薯杂种优势的表现是以亲本自身生产力高低为前题的,由自身生产力较低的亲本产生的杂种群体,即使具有较高的杂合性,与也很难表现较高的产量,只有对亲本加以选择和在改造的基础上利用,才能充分表现其杂种优势。 2.Neo-tuberosum参与杂交的组合,优于其它类型的杂种群体,是目前马铃薯新品种和实生种子选育的最优组合方式。 3.杂种群体薯形,皮色和芽眼深浅等经济性状的一致性表现于群体的杂合性程度相关不同,而与两亲本在这些性状上的差异有关。因此选择在性状上差异较小的亲本杂交,是获得整齐一致实生种子的关键。     

轮回422与籼稻杂交F1抽穗期超亲遗传分析

 分析了偏粳型广亲和品种轮回422与籼稻品种南京11、I188025（具有簇生小穗标记基因Cl）杂交F₁～F₃及BC₁在不同日长条件下的抽穗期表现。长日照试验表明，F₁超亲迟熟（超亲优势率达49%）主要受两对互补基因控制。短日照试验结果证明，杂种超亲迟熟主要由其强感光性引起的，上述互补基因属于感光性基因．通过互补测验和连锁分析证明，两籼稻亲本所携互补基因为等位关系，此基因与6号染色体上的Cl基因连锁，重组率为27.78%±1.82%。根据试验结果可以认为，感光性基因的互补作用是造成籼粳杂种一代生育期超亲迟熟的主要遗传原因。     

小麦轮回选择的若干问题

一、轮选亲本选配问题选用适当亲本，合理配制组合是杂交育种工作成败的关键。轮回选择亲本的选配也不例外。在某种意义上说，甚至更为重要。因为轮回选择所用的亲本较多，既利用分离重组规律，也利用基因加性效应，创造超亲性状的重组体。基础群体是要多亲本通过多年个体间随机互交，将亲本基因尽多地转移到杂种群体中，形成一个贮备优良基因的杂合群体，作为论选的基础材料。轮回选择亲本选配时要借鉴常规竟种的亲本选配原则，考虑目标c。状一一frfy，一般配合力；要考虑到产量等农艺性状的优良，也要考虑抗性和对当地主态条件的适应征。…     

甘蓝型油菜花色性状的遗传研究

以甘蓝型油菜白花和金黄花突变体及正常黄花亲本为材料 ,研究油菜花色性状的遗传表现。结果表明 ,白花对黄花由一对不完全显性基因 WW控制 ,杂合体 Ww表现为乳白花 ;黄花对金黄花是由二对具有重叠作用的显性基因 Y1 Y1 Y2 Y2 控制 ;白花对金黄花有三对基因差异 ,其中白花基因具有上位性作用 ,只需一个白花基因 W存在 ,即可抑制黄花与金黄花性状的表达。因此 ,油菜花色性状是由不同的等位基因控制的 ,而不是由复等位基因控制。 3个亲本的基因型分别是 :白花亲本为 WWY1 Y1 Y2 Y2 ,黄花亲本为 ww Y1 Y1 Y2 Y2 ,金黄花亲本为 wwy1 y1 y2 y2 。     

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.