玉米自交系通9137的选育及应用

通9137是通辽市农业科学院执行内蒙古自治区“九五”攻关课题过程中选育的玉米自交系,是以铁7922×沈5003×铁7922为基础选育的二环系,该自交系具有较强的抗逆性,高抗玉米大小斑病、高抗灰斑病,高抗玉米螟。通9137配合力高,由它组配的杂交种在生产中被大面积推广。     

铁7922衍生系在玉米育种及生产上的应用

玉米自交系铁7922株型紧凑,茎秆坚韧,品质优良,配合力高,抗逆性强,遗传性状稳定,适应范围广,是国内改良Reid类群的骨干自交系之一,同时也是选育玉米自交系的优异种质资源。许多育种者围绕铁7922的改良创新,选育自交系达40余个,组配的杂交种通过国家和省级审定有60余个。其中代表品种有铁单10号、铁单12号、铁单15号、铁单18号、丹玉26、丹玉39号、丹玉69、辽120、通吉100、沈玉22号、濮单3号、濮单6号、东单8、东单13、东单60等。可见,铁7922衍生系在玉米生产上同样有着重要的地位。     

铁7922改良效果及与苏湾种质系的配合力研究

采用NC-Ⅱ遗传交配设计,以铁7922及其9个改良系为母本,10个苏湾种质系为测验种,组配100个杂交组合,应用部分平衡格子方进行1年3点田间鉴定,评价优良玉米自交系铁7922的改良效果,探索改良新系的利用潜力。结果表明,改良新系T123、1164、QR29的利用价值大;440-4、1061、QR25具有一定的利用潜力;A26、A30、21170改良效果差、利用价值低;S273、S909、927、T32是良好的测验系。铁7922及其改良系×苏湾系杂交模式优势明显,可进一步应用瑞德×苏湾杂种优势模式。     

高淀粉、高产、多抗玉米杂交种正红115的选育研究

以美国玉米带杂交种3163为基础材料,通过南北穿梭同步定向育种新方法,用自交系48-2作测验种在S1和S3早期分离世代连续进行早代测定和定向选育,同步育成玉米新自交系K169及其组配的杂交种正红115(K169×48-2)。正红115子粒粗淀粉含量高达75.7%,并具有综合品质优、产量高、抗病及抗倒伏力强、株型好和适应性广等特点。正红115适宜丘陵山区种植,具有广阔的推广应用及加工利用前景。     

低磷胁迫下玉米自交系配合力分析

缺磷是限制作物生产的重要因素之一。通过遗传改良提高玉米杂交种的磷吸收利用能力,是提高磷肥利用率的一条重要途径。本研究利用磷肥长期定位田,在前期磷高效自交系筛选的基础上,对低磷胁迫下玉米自交系的配合力进行分析,以期为磷高效育种选择亲本提供依据。研究结果表明,鲁原92×7922为高磷高效型杂交组合,减产率达67.2%;Mo17×7922为低磷高效型杂交组合,减产率只有3.5%。耐低磷育种中,高配合力自交系为CA200和Mo17;低配合力自交系为丹黄02、107、原引1号、鲁原92、3189、Oh43和黄C;中配合力自交系为91041-1、CA170、L种和7922。低磷条件下,组合产量与空秆率、成熟期熟相呈负相关,即早熟型且空秆少的玉米品种较为耐低磷胁迫。     

玉米自交系铁7922苗期耐低氮胁迫原因探讨

以低氮胁迫(NO3--N0.2mmol/L)与正常供氮(NO3--N2mmol/L)条件下的生物量比值作为耐低氮能力指标,从12份玉米自交系中筛选出在低氮胁迫条件下苗期能够正常生长的自交系铁7922。通过不同玉米自交系对低氮胁迫反应差异的比较研究,从根系与氮利用效率对低氮环境的响应以及硝酸盐吸收动力学等3个方面对铁7922耐低氮原因进行了探讨。结果表明,铁7922对低氮环境的适应是多因素共同作用的结果,表现在氮胁迫浓度下根干重的增加、氮利用效率的显著提高以及较小的Km和低的Cmin。单纯的根干重的增加(掖515)或氮利用效率的提高(H21)或较小的Km(4F1、豫8701)并不能保证在低氮环境的正常生长。     

25个优良温带玉米自交系与4个热带玉米自交系农艺性状的配合力研究

采用NCⅡ设计对25个优良温带玉米自交系和4个热带自交系配制100个杂交组合,在云南省3种不同生态环境下对这些杂交组合进行农艺性状和产量配合力分析。结果表明,温带自交系郑58、K1218是综合性状配合力十分优良的自交系;铁7922、辽3180是综合性状配合力优良的自交系;自330、丹340、云147、81515、西502等是综合性状配合力比较优良的自交系。热带自交系单株产量GCA效应值YML146>YML145>CML171>CML166,温带系×Suwan1和温带系×Tuxpeno是主要的杂种优势模式。将4个热带自交系分别用TA(热带硬粒型)和TB(热带马齿型)来表示,有以下几种类型:①某温带自交系×TA为强优势组合,同一温带自交系×TB也是强优势组合;②某温带自交系×TA为强优势组合,同一温带自交系×TB是弱优势组合;③某温带自交系×TA为弱优势组合,同一温带自交系×TB也是弱优势组合。     

玉米自交系铁7922的改良利用

分析以自交系铁7922为主线的改良进程,明确铁7922改良系与黄系、旅系、黄旅合成系测配组合的优、缺点.以铁7922改良系为基础,添加外来相对应种质进行母本改良,以黄、旅合成系与Lancaster进行父本改良,利用单倍体技术选育区域强势品种.     

基于SSR标记的玉米循环群体选系材料的遗传基础分析

利用SSR标记技术对53份玉米循环群体选系材料和9个测验种进行分析,分析其遗传多样性,明确其遗传距离和杂种优势群划分,从分子遗传基础角度为循环育种策略奠定基础。结果表明,39个SSR标记在62份材料中共检测出162个等位基因变异,铁7922改良系和吉13S228改良系中分别检测出83、140个等位基因变异,位点多态性信息指数(PIC)平均分别为0.45、0.26、0.37;基因多样性指数平均分别为0.51、0.31、0.42;吉13S228改良系的遗传多样性高于铁7922改良系。遗传距离变幅在0.11～1.87,平均0.76;吉13S228改良系群体与吉13S228间的遗传距离最小(0.09),铁7922改良系群体与铁7922间的遗传距离亦较近(0.16),揭示改良系的遗传背景以改良受体为主。按照UPGMA聚类法、主成分分析和模型聚类方法,划分为两大类群,SS群(铁7922及其循环选系材料、B73、掖478等)和NSS群(吉13S228及其循环选系材料和标准测验种Mo17、丹340、黄早四等),符合玉米商业育种的两个杂种优势群的思路。     

导入外源DNA改良玉米自交系

该项目研究是将优良玉米自交系丹340、巴西抗病玉米杂交种以及大豆的总DNA,通过花粉管通道法分别导入玉米自交系7922、E28和黄428,对花粉管导入技术进行研究。改良7922自交系的株高和穗位比对照平均降低44 cm和22 cm;改良E28自交系S6的抗病性显著提高;改良黄428自交系A33和A35的干物质含量明显增加。     

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.