小麦新品系的赤霉病抗性及分子标记分析

为有效降低赤霉病对我国黄淮麦区小麦生产的影响，培育抗赤霉病小麦新品种，以自主创制的13个抗赤霉病稳定的小麦新品系为材料，利用赤霉病菌地表接种和单花滴注法接种鉴定、分子标记检测等技术，鉴定其抗病性、主要农艺性状及赤霉病抗性相关的遗传基础。结果表明：（1）品系Xn12-2和Xn13-2对赤霉病表现为抗，平均病小穗率为11.5%和13.4%，严重度为1.9；其余11个品系表现中抗，平均病小穗率均小于30%，严重度均小于3.0，其中4个品系（Xn12-2、Xn10-2、Xn12-3和Xn12-7）兼抗条锈病；（2）参试新品系的越冬抗寒性较好，株高较矮（67~82 cm），穗较长（9.6~11.3 cm），千粒重高（39.2~50.2 g）；（3）11个品系携带有苏麦3号的Fhb1基因，部分品系兼具苏麦3号的Fhb2、Fhb5或QFhs.crc-2DL位点的优异等位变异。综上所述，参试部分品系不仅具有良好的赤霉病和条锈病抗性，其主要农艺性状基本满足黄淮南部麦区的主要育种目标要求，可作为小麦抗赤霉病改良的材料。     

小麦抗赤霉病主效QTL的聚合效应分析

为了明确小麦抗赤霉病主效QTL的抗病效应,基于分子标记辅助选择,将来源于抗病品种苏麦3号的Fhb1、Fhb2和望水白的Fhb4、Fhb5回交导入感病品种矮抗58中,构建出30个不同QTL组合的株系,分别采用单花滴注和喷洒孢子悬浮液接种法,对其开展抗侵入、抗扩展和综合抗性鉴定。结果表明,携带Fhb1和Fhb2的株系表现出显著的抗扩展能力,Fhb1的效应显著高于Fhb2,但二者都没有抗侵入效应;携带Fhb4和Fhb5的株系表现出明显的抗侵入性,二者累加后效应更显著,但均没有明显的抗扩展能力;不同抗性类型的QTL聚合后,其综合抗病性比单个QTL更显著。说明在育种中,将不同抗性类型的QTL聚合后比单个QTL的抗赤霉病效果更佳。     

小麦抗赤霉病性田间自然鉴定与抗赤霉病育种中的问题探讨

198 4年以来 ,承接了全国小麦育种攻关中的小麦抗赤霉病性鉴定任务 ,对来自全国 10个麦区 12 6 4 8份小麦育种材料抗赤霉病性进行田间自然鉴定。结果表明 ,至今仍未发现免疫的小麦材料。长江中下游冬麦区、华南冬麦区及东北春麦区的供鉴小麦抗性较强 ,全国R级小麦材料均分布在这些赤霉病频繁流行的麦区 :西南冬麦区、黄淮冬麦区及北部春麦区的供鉴小麦抗性较弱 :北部冬麦区、青藏春冬麦区、西北春麦区及新疆冬春麦区的供鉴小麦抗性最差。我国现有小麦材料的抗病性与丰产性仍存在较大矛盾 ,至今仍缺乏可应用于生产的抗赤霉病高产小麦新品种。对我国小麦抗赤霉病育种尚未取得较大突破的原因进行了分析 ,并探讨了相应的解决办法 ,提出在病区建立小麦抗赤霉病穿梭育种开放试验基地的设想     

小麦种质材料赤霉病抗性鉴定及遗传多样性分析

为筛选小麦抗赤霉病优异种质,探究不同抗源的亲缘关系,以苏麦3号、扬麦158和矮抗58分别作为高抗、中抗和高感对照,2017-2018年采用病麦粒土表接种法从345个小麦育成品种（系）中初步筛选出94个抗赤霉材料,2018-2019年在此基础上对这94个品种（系）再次进行病麦粒土表接种和单花滴注接种鉴定,并进行SSR分子标记遗传多样性分析,同时对综合鉴定表现抗赤霉病的品种（系）进行农艺性状调查。结果表明,初选的94个品种（系）中分别有51、41和2个品种（系）中抗、中感和高感赤霉病。 包括3个对照在内的97个品种（系）间遗传距离为0.02~0.74,平均为0.42;通过UPGMA聚类将97个品种（系）划分为7个类群,51个中抗品种（系）分布在Ⅰ至Ⅶ类群中,其数量分别为15、13、14、2、1、1和5个,其中Ⅰ、Ⅱ和Ⅲ类群中的分布数量占品种（系）总数的82.4%;51个中抗品种（系）的农艺性状变异较大,Y608、庆丰188、宁丰518、明麦7号、宁麦资15116、金运麦4号、zhb003、科运麦1611和华鉴麦3号等9个品种（系）的综合农艺性状表现良好,生育期适中,株高在74.67~84.67 cm,单株产量和千粒重分别都在7.5和45 g以上。     

利用Fhb1基因分子标记辅助回交育种法改良黄淮冬小麦赤霉病抗性

黄淮冬麦区小麦赤霉病的发生流行程度年际间变化较大,给赤霉病抗性品种的田间选择造成很大困难,因此分子标记辅助选择育种技术的应用显得尤为重要。为明确 Fhb1基因在轮选136背景下对赤霉病抗性的影响,本研究以6个长江中下游麦区抗赤霉病品种(系)为供体,与黄淮冬麦区骨干亲本周麦16的矮败小麦近等基因系进行杂交,并分别与周麦16及其衍生品系轮选136进行2次回交,创建6个BC_2回交育种群体。利用功能标记跟踪后代 Fhb1基因,结合单花滴注接种和自然发病鉴定,检测分子标记选择的效果。根据三个环境表型鉴定结果,发现161个携带 Fhb1抗性等位基因( Fhb1-R)的BC_2F_3株系平均病小穗数和严重度均低于中感赤霉病对照淮麦20和轮回亲本轮选136。其中,60个BC_2F_3株系(37.3%)的病小穗数和严重度在三个环境下表现一致,显著低于淮麦20。在入选的122个BC_2F_4品系中,93个品系(76.2%)的赤霉病抗性优于淮麦20,36个品系(29.5%)优于或相当于中抗对照扬麦158。基因型分析结果表明,赤霉病抗性优于淮麦20的93个BC_2F_4品系除了携带 Fhb1-R外,还携带轮选136的抗性位点 Qfhb.7D。本研究为黄淮冬麦区小麦抗赤霉病分子标记辅助选择育种提供了重要信息和育种材料。     

59份江苏小麦品种（系）的抗赤霉病评价与农艺性状分析

赤霉病是小麦的重要病害,严重影响小麦产量和品质。为发掘赤霉病的抗性种质资源和抗性基因,本研究分别以苏麦3号、扬麦158、扬麦15和安农8455为高抗、中抗、中感和高感赤霉病对照品种,于2016-2017和2017-2018连续2年对来自江苏的59份小麦品种（系）采用单花滴注接种法进行田间赤霉病抗性鉴定,同时利用与 Fhb1 、 Fhb2 、 Fhb4 、 Fhb5 和 QFhs.crc-2DL 连锁的分子标记对供试材料进行检测,并对赤霉病表现为稳定中抗及以上水平品种（系）的千粒重、株高、穗粒数等农艺性状进行调查。结果表明,59份供试小麦品种（系）中,19份在两个年度均表现为中抗。分子标记检测发现,9份小麦品种（系）仅携带 Fhb1 ,平均病小穗率为22.21%;10份小麦品种（系）仅携带 QFhs.crc-2DL ,平均病小穗率为27.82%;携带 Fhb2 、 Fhb4 和 Fhb5 基因的品种（系）较少。镇麦12号、宁麦1529、宁麦27、镇麦13322、宁麦17110、镇麦13、宁麦17108和宁麦17396的赤霉病抗性和综合农艺性状均较好,可以作为小麦抗赤霉病遗传改良的种质资源。     

小麦品种望水白的抗赤霉病性遗传分析

为了研究小麦品种抗赤霉病性的遗传规律,以病小穗率为评价指标,运用单花滴注对安农8455/望水白重组自交系(R IL)群体的2001年F6代、2003年F8代、2004年F9代进行了赤霉病抗性评价,采用植物数量性状主基因 多基因混合遗传模型分离分析法,研究了该群体抗赤霉病的遗传规律。结果表明,安农8455/望水白重组自交系群体3年的抗赤霉病性分别符合E-2-6模型(两对主基因 多基因的加性-加性模型)、E-1-8模型(两对主基因 多基因,主基因间为重叠作用)、E-1-8模型(两对主基因 多基因,主基因间为重叠作用)。主基因的遗传率较高,分别为63.8%、69.02%、73.66%,多基因的遗传率分别为21.80%、21.38%、16.80%。说明望水白的抗赤霉病性由2对主基因控制,且符合两对主基因 多基因模型。还对望水白与另一感病品种A londra构成的重组自交系的抗性进行了比较。     

45份小麦种质赤霉病抗性评价与农艺性状分析

为获得农艺性状较好且抗赤霉病的种质资源、加快小麦抗赤霉病育种进程,以禾谷镰刀菌(Fusarium graminearum Schw.)菌株F15为致病菌,分别以苏麦3号与09X15作为抗病与感病对照,于2015-2017年对收集自南京农业大学等7个研究单位的45个小麦材料进行了大田赤霉病抗性鉴定与农艺性状调查,利用分子标记检测小麦种质所携带的 Fhb1基因。结果表明,在用微量移液器进行单花滴注接种鉴定的三年试验中,NMAS001、苏麦3号、P48等13个小麦材料至少有两年表现抗病。利用抗赤霉病主效QTL的SSR标记Xgwm493、 Xgwm533和Xbarc147对45个小麦材料进行 Fhb1基因的分子检测表明,苏麦3号、NMAS020、苏夫等20个小麦材料含有 Fhb1基因。抗赤霉病小麦材料一般主要农艺性状如株高、穗粒数、千粒重等表现不良;15HN018、15HN200和宁麦9号的抗赤霉性和农艺性状均较好。     

国内外部分小麦材料在黄淮麦区的抗赤霉扩展特性及农艺性状研究

为筛选适宜黄淮麦区的小麦抗赤霉病育种材料,研究了国内外32个小麦材料在黄淮麦区的抗赤霉扩展特性及农艺性状。结果表明,32个材料人工接种均发病,但材料间发：病程度差异很大：其中高抗类型6个,中抗类型12个,中感类型9个,感病类型5个。通过对供试材料的主要农艺性状与抗赤霉扩展特性进行了相关分析,株高、穗长、穗密度等农艺性状与小麦抗赤霉扩展特性无相关性。     

小麦地方品种黄方柱中赤霉病主效抗性位点 Fhb1的精细定位

位于小麦3BS染色体上的赤霉病抗性主效基因Fhb1的效应较大而且比较稳定,是培育抗赤霉病品种最常用和最可靠的位点。我国小麦地方品种黄方柱（HFZ）高抗赤霉病且在3BS染色体上携带Fhb1基因。本研究对HFZ/Wheaton重组自交系（RIL）群体的Fhb1位点进行分子标记检测,筛选到两个杂合子株系,并对这两个杂合子株系连续自交3代,衍生出2个次级分离群体（L30和L112）,将这两个次级分离群体在扬州大学农学院试验田种植,并在扬花期进行单花滴注接种鉴定赤霉病,调查这两个群体中各株系的病小穗数、病小穗率、病粒数和病粒率。结果表明,L30和L112两个群体的病小穗数和病小穗率均显著正相关,病粒数和病粒率均显著正相关。同时依据小麦3B染色体参考序列开发了7个新的多态性标记,分别是 X1550、X2214、X2300、X2357、X2455、X2460和X2467。用这些多态性分子标记进行基因型检测,在目标位点发现5个交换株系,根据基因型和病小穗率,进一步将Fhb1定位在分子标记 X2214与 X2357之间,在ctg0954b上这两个分子标记之间的物理距离约为143 kb,NCBI预测该区间有3个候选基因,但是FGENESH在相同区段预测了29个基因,说明目标区段所具有的基因数目很可能多于3个,但少于29个。     

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.