“三系”杂交棉组合F1花粉育性与产量和品质的相关性研究

细胞质雄性不育“三系”（不育系、保持系和恢复系）制种因简化制种和节约劳动力成本已成为棉花杂种优势利用的重要手段。研究棉花花粉育性及“三系”组合F1可育花粉率与产量、品质性状的相关性，可以达到强化“三系”制种，提高育种效率的目的。用联苯胺-甲萘酚法测定12个不育系与4个恢复系杂交所得的48个F1的花粉育性，统计了可育花粉率并分析了可育花粉率与产量、品质的相关性。结果表明：－20℃保存条件下，花粉育性随贮藏时间的增加而减弱，51 h内其花粉育性依然保持88%以上，51 h内花粉育性无显著性影响。F1的可育花粉率均低于其恢复系及常规杂交种，大部分组合降低水平在20百分点以内。不同恢复系的恢复力有明显差异, 其中H46恢复力较强。F1的可育花粉率与单株铃数呈显著正相关。本研究结果有助于了解离体花粉的育性变化规律及“三系”杂交组合后代可育花粉率与产量品质的关系，可应用于异地授粉并在一定程度上指导“三系”杂交种选育，为育种工作提供一定的参考。     

泰安市农科所利用雄性不育选出玉米新种质及新杂交组合

20 0 2年 7月 2 7日 ,受山东省科技厅委托 ,泰安市科技局组织并邀请了中国农科院、山东农业大学、莱阳农学院等有关单位的同行专家对泰安市农业科学研究所、泰安市鲁中种业有限责任公司选育的S型玉米雄性不育基因转育的新种质ST0 2 9、ST0 39两个雄性不育优良自交系和强恢复ST5 0 1、完全不育ST6 18两个杂交新组合进行了技术鉴定。鉴定委员会一致认为 :该项研究成果在同类研究中达到了国内领先水平 ,在玉米不育化育种方面取得了重大突破。1 该项目利用S型玉米雄性不育系与优良玉米自交系为材料 ,通过生物技术手段创造新的玉米雄性不育新…     

玉米新品种京丰8号的选育

玉米新品种京丰8号是利用玉米不育系配制的杂交种。玉米的雄性不育系是指玉米雄蕊发育不正常,不能产生有功能的花粉,但雌蕊发育正常,能接受正常花粉而受精结实,并能将雄性不育性遗传给后代的植物品系。玉米杂交制种的去雄工作十分辛苦,在去雄期必须每天去雄,风雨无阻,     

棉花光温敏核不育系396A育性特征及杂种优势分析

棉花光温敏核雄性不育系396A是从海陆杂种后代中发现的具有芽黄标记性状的新型核雄性不育系。为探明该不育系在不同温度和光照条件下的育性表现及其杂种优势表现,分别在新疆博乐和三亚海棠湾进行试验,研究了该不育系的育性变化及其杂交种的产量性状、抗病性、纤维品质。结果表明:棉花光温敏核雄性不育系在三亚种植可正常恢复育性,且花粉量大,自交成铃率高,能够自然繁殖;在博乐表现为雄性不育,没有花粉,自交成铃率为0,不育度100%,且配合力好,恢复源广阔,恢复能力强,可作为母本进行杂交制种;其杂交种F_1代育性恢复好,花粉量大,全部能够自然成铃且杂种优势明显,其中,部分杂交种产量高、抗病性好、纤维品质优良,表现出较强的杂种优势。     

京724玉米自交系S型细胞质雄性不育系分子标记辅助选育研究

以自育的S型细胞质雄性不育系MD32为供体,京科968的母本京724为受体,利用回交转育结合分子标记辅助背景选择,仅回交3代即获得京724遗传背景的S型细胞质雄性不育系。经花粉I2-KI染色鉴定,京724不育系花粉败育完全。     

玉米雄性不育系C天4~(ms)的选育研究

用常规的回交转育法选育出玉米雄性不育系Ｃ天４ｍｓ。经田间鉴定其雄穗花药不外露，花粉败育彻底，不育性稳定。用Ｃ天４ｍｓ配制的户单４号杂种一代表现为雄性不育。其主要农艺性状与正常可育的户单４号基本相似，子粒产量比正常可育的户单４号增产６．９％。可以用掺合法在生产上利用Ｃ天４ｍｓ配制的户单４号杂交种。     

玉米细胞质雄性不育系JnA的育性遗传分析及分组鉴定

通过对玉米细胞质雄性不育系JnA的花药、花粉形态观察,恢保关系鉴定,F2代育性分离观察及F1代花粉碘液染色镜检,初步确定JnA应属于S组细胞质雄性不育。从JnA×恢313的F2出现少量不育株和半恢株的情况看,JnA不育性的恢复既受主效基因控制,又受微效多基因控制。细胞学观察发现,JnA的败育时期发生在单核晚期至二核花粉期,败育发生与绒毡层解体异常有关。     

甘蓝型油菜无花瓣品系雄蕊雌化不育系的发现和遗传研究

1998年在自选的甘蓝型无花瓣油菜株系中发现了一种突变不育株,进而育成无花瓣油菜突变不育系(简称AMS).经连续4年研究,结果表明:该雄性不育系不育性彻底,是一种雄性器官雌性化而引起的新的不育现象,其植株形态特征与无花瓣相同.用来自国内外不同品种(系)和胞质雄性不育系的保持系、恢复系及杂种F1共549份材料配制了779个杂交组合,全部恢复育性.2002和2003年收获的100个杂交组合有29份较对照(秦优7号杂交种)增产5.7%～23.5%,达显著水平.该突变不育株与可育株测交,后代不育和可育符合1:1的遗传分离模式,经对AMS测交、杂种自交,表明不育性很可能由4对隐性基因控制.     

一种新型玉米雄花不育材料的发现

现有玉米细胞质雄性不育（CMS）的C，T，S型不育型均为母性遗传。作者从1992年发现父、母本均完全可育，而其特定组合的F₁完全不育的新一类玉米雄性不育材料。经几年观察此类材料后代，多数植株不育性状较为稳定。为此将此类父、母本可育，F₁选择性不育的雄花不育材料定义力“特殊雄性不育型”，简称““特型”，以示区别。     

水稻质核互作雄性不育系的微效恢复基因定位和排除方法研究

以232个协青早A/B456///协青早A/B456∥B456植株组成的分离群体为材料,调查花粉可育率和自交结实率,并采用121个在染色体上分布比较均匀的SSR多态性标记进行QTL检测。发现22个SSR标记分别与10个花粉育性位点连锁,分布于第2,5,6,8,10,12染色体上;28个标记分别与16个小穗育性位点连锁,分布于第1,2,4,5,6,8,10和11染色体上;13个标记同时与花粉育性和小穗育性连锁,小穗育性与花粉育性QTL差异是花粉可育度和自交结实率不平行性的遗传基础。各可育位点对花粉育性和小穗育性的提高效应比较小,为微效基因,但每个花粉育性位点的存在都可导致不育系败育不彻底。协青早A中发现1个花粉可育位点Pf5-1,与分子标记Bm55和Rm13紧密连锁,进行分子标记辅助选择,可能排除协青早A的微效恢复基因(可育位点),达到完全不育。协青早A存在8个小穗育性位点,能够提高自交结实率,有助于杂种F1结实率的提高,有利于提高不育系的可恢复性。多数微效恢复基因显示为部分隐性或隐性,是水稻质核互作雄性不育系选育难的重要原因。采用不育系/拟用亲本∥保持系/拟用亲本的方式,观察杂种育性分离,可对拟用亲本的微效恢复基因有所了解,用保持系/部分保持系∥保持系的方式可提高微效恢复基因排除的效率。     

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.