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1.
[目的]研究6个采自不同种源地的橡实的萌发特性。[方法]测定分析各不同种源地的橡实千粒重大小、种长、种宽、优良度、发芽率。[结果]不同种源地橡实的形态特征之间存在显著差异(P<0.05),橡实千粒重为1.43~3.43 kg,橡实种长为1.59~2.10 cm,橡实种宽为1.29~1.78 cm,不同种源地优良度、发芽率之间存在显著差异。[结论]不同种源地橡实萌发特性存在显著差异,其中内蒙古扎赉特旗橡实优良度、发芽率均最高,可作为采集橡实进行蒙古栎育苗的首选地。  相似文献   

2.
对来自贵州、湖北3个地理种源的伯乐树(Bretschneidera sinensis)在贵州都匀进行了苗期试验。结果表明,伯乐树从子叶出土到当年幼苗停止生长可分为“出苗期”、“生长初期”、“速生期”和“生长后期”4个阶段,径生长比高生长提早约10 d进入速生期而晚10 d停止生长;3个地理种源种子性状差异主要体现在千粒重和种子大小上,贵州2个种源明显大于湖北五峰种源;贵州2个种源苗高和地径各阶段生长期基本一致,湖北五峰种源比贵州2个种源高生长晚进入速生期,且提早停止生长;种源间与种源内均存在较大的变异;种  相似文献   

3.
[目的]分析冬瓜种子的休眠类型,为选择破除其休眠的措施提供理论依据.[方法]对种子进行剥除种皮、夹裂种孔处理,观测种子生活力、种子发芽率、种皮吸水率和透气性,并浸提种仁内的醇溶性萌发抑制物质进行生物检测.[结果]完整未处理的种子生活力远高于其发芽率;未处理种子的发芽率明显低于剥除种皮种子,但与夹裂种孔的种子发芽率无明显...  相似文献   

4.
[目的]培育优质健壮湿地松苗木,提高造林成活率。[方法]湿地松大田育苗在出圃前进行二次切根,调查其苗高、地径、侧根数、须根数等因子,并与未切根苗生长情况进行比较。[结果]经方差和多重比较分析,与未切根苗相比,湿地松二次切根苗的侧根数、侧根总长、须根数均显著增加,切根时间以9月中旬为佳。[结论]湿地松二次切根苗木根系发达,有利于造林成活率的提高。  相似文献   

5.
为揭示不同种源多油辣木(Moringa oleiferaLam.)的形态多样性、变异程度以及各种源的表型特点。对云南省引种栽培的世界范围内10个种源多油辣木的15个表型数量性状和质量性状进行差异性研究。结果表明,不同种源多油辣木的形态学特征存在广泛的变异,其中复叶长变异幅度最大,变异范围为6.052~14.325 cm,变异系数为25.192%,其次为种子千粒重、小叶长、种子长和小叶宽,而小叶对数的变异幅度最小,变异范围为4~6,变异系数为9.420%,侧脉数目和可育花药数量无表型变异;主成分分析显示多油辣木种源间的形态差异主要来源于小叶面积、小叶长、花瓣颜色、小叶叶型和种子长;UPGMA聚类分析表明,10个种源可以归为两大类群,其中中国台湾、缅甸实皆与印度南部班加罗尔的种源归为一个类群,缅甸木各具、肯尼亚、美国、古巴与印度北部新德里的种源归为另一个类群。不同种源地的多油辣木在其种源地因人为筛选或环境适应而形成了在叶片和种子的形态指标上较高的形态分化,因此,建议不同种源在良种选育时可根据利用部位的不同而选择培育方向。  相似文献   

6.
内源激素驱动下的千年桐种源优选   总被引:1,自引:0,他引:1  
收集福建省11个千年桐种源种子,并于2010年按随机区组设计在福建省建阳市蕉溪采育场进行田间试验。本试验设置12个区组,每区组设11个小区,每小区面积100 m2,每小区栽植25株,测量其苗高、地径。采取二年生叶片,采用间接酶联免疫法(ELISA)测定引种的11个种源的GA3、ZR、IAA、ABA 4种内源激素,并用改进的投影寻踪方法,用投影值的大小确定优良种源。结果显示:种源的优劣排序为莆田>政和>周宁>尤溪>建阳>屏南>沙县>福鼎>柘荣>蕉城>福安。从内源激素对千年桐生长的影响角度进行优良种源的选择,为种源早期选择提供新方法。  相似文献   

7.
冬瓜种子千粒重主基因+多基因混合遗传分析   总被引:1,自引:0,他引:1  
利用主基因+多基因混合遗传模型对冬瓜组合B214(小籽粒)×B227(大籽粒)的6世代群体(P1、P2、F1、B1、B2及F2)种子千粒重进行遗传分析.结果表明,冬瓜组合B214×B227种子千粒重性状为1对加性主基因+加性-显性多基因遗传,主要受主基因和多基因的加性效应控制,不存在杂种优势.主基因+多基因在B1、B2及F2群体的遗传率分别为68.82%、75.70%和76.29%.因此,可通过选择较高千粒重的材料为亲本,利用加性效应对冬瓜种子千粒重性状进行品种改良.  相似文献   

8.
介绍热带亚热带果树种质资源的收集保存及评价情况,阐明作为园林植物的果树品种资源应具备的特性及应用功能。根据资源评价结果,筛选出适用于园林绿化的热带亚热带果树品种资源,并提出热带亚热带果树品种资源作为园林植物应用的可持续发展建议。  相似文献   

9.
杨镇  孙平 《杂粮作物》1999,19(6):29-30
墨西哥国际玉米小麦改良中心(CIMMYT)是一个规模大、学科全、成就显著和影响大的国际研究机构,由洛克菲勒集团提供研究经费,近年来,由于生物技术和计算机技术的迅速发展,CIMMYT的玉米遗传育种领域有了很大的进展,它们的优势主要表现在资源研究及种质创新和新技术的应用等方面,玉米育种工作的重点是开发应用种质,进行热带、亚热带种质改良,从改良群体选择优良自交系,培育玉米优良品种。1 热带、亚热带玉米种质研究CIMMYT玉米研究的起始阶段,广泛收集热带、亚热带及温带种质群体,根据生育期、籽粒色泽合成…  相似文献   

10.
[目的]研究NaC1胁迫对萝卜种子萌发及幼苗生长的影响,为萝卜在盐胁迫土地上高产栽培及抗盐育种方面提供理论依据。[方法]采用培养皿纸上发芽法,探讨了NaCl胁迫对萝卜种子萌发及幼苗生长的影响。[结果]随着NaCl浓度的增加,萝卜种子发芽率、萝卜幼苗的根长和苗长均呈下降趋势。但NaCl对萝卜种子的发芽率没有显著性影响。[结论]NaCl对萝卜幼苗生长的影响大于其对萝卜种子萌发的影响。  相似文献   

11.
12.
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.  相似文献   

13.
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.  相似文献   

14.
15.
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.  相似文献   

16.
Novel food and non-food uses for sorghum and millets   总被引:4,自引:3,他引:4  
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.  相似文献   

17.
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.  相似文献   

18.
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 RXact).  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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