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关键词： Salvia albicaulis   Salvia dolomitica   antibacterial   antiplasmodial   anti-inflammatory   anti-oxidant   toxicity   essential oil   linalool   geraniol   linalyl acetate   viridiflorol   trichomes  

摘要： An investigation of leaf indumentum, the identification of the essential oil components and assessment of various biological activities of Salvia albicaulis and S. dolomitica essential oils were carried out. Non-glandular and both peltate and capitate glandular trichomes were identified using scanning electron microscopy. The essential oil of S. albicaulis was dominated by oxygen-containing sesquiterpenes (47%), with viridiflorol (25%), 1,8-cineole (9%) and limonene (9%) as major components. S. dolomitica oil was mainly composed of oxygen-containing monoterpenes (72%), with geraniol (20%), linalyl acetate (20%) and linalool (17%) being the major components. The in vitro pharmacological properties of the essential oils were also evaluated. Antibacterial activity was assessed against Staphylococcus aureus (ATCC 25923), Bacillus cereus (ATCC 11778), Escherichia coli (ATCC 8739) and Klebsiella pneumoniae (NCTC 9633). The oils showed poor activity against E. coli (MIC value > 32 mg ml(-1)), while moderate activity was obtained against the other pathogens (MIC values between 2 and 12 mg ml(-1)). The results of the antiplasmodial activity evaluated against the chloroquine-resistant FCR-3 strain showed that both S. albicaulis and S. dolomitica essential oils exhibited antiplasmodial activity with IC50 values of 6 +/- 2 and 5 +/- 1 mu g ml(-1), respectively. The two oils also displayed anti-inflammatory activity (IC50 value: 39 +/- 4 and 65 +/- 6 mu g ml(-1), respectively). Poor anti-oxidant activity was obtained against the DPPH and the ABTS(+) radicals (IC50 values > 100 mu g ml(-1)). The toxicity profile of the two oils evaluated against the human kidney epithelium cells indicated some degree of toxicity in comparison to 5'-fluoro-uracil. (c) 2006 SAAB. Published by Elsevier B.V. All rights reserved.

关键词： Ophelimus maskelli   gall   eucalyptus   Eulophidae   host plants   egg distribution   damage   seasonal development   leaf survival   feed effect  

摘要： Ophelimus maskelli (Ashmead) (Hymenoptera: Eulophidae), an invasive species in the Mediterranean area that occurs naturally on Eucalyptus camaldulensis at Wagga Wagga in New South Wales, was studied in Israel on the same host plant. The most distinctive characteristic of O. maskelli as compared with other congeners is the presence of only a single seta on the submarginal vein. O. maskelli shows a clear tendency to oviposit in developed, immature leaves, and it prefers to oviposit on an area of the leaf blade near the petiole. The female lays an average of 109 eggs when maintained on water alone. The egg-laying distribution tended towards aggregation, and the same tendency has also been observed within and among trees. The wasp prefers to attack the lower canopy. The gall diameter 2 ranged from 1.2 to 0.9 mm, and gall density from 11.5 to 36.0 galls cm(-2) respectively. The typical color of the gall appeared as soon as third instar larva developed. Galls on shaded leaves remained green or greenish-yellow, whereas those that were exposed to the sun were reddish. O. maskelli produces three generations per year in Israel. High flight occurs among the spring generations, starting in early March. The wasps were attracted to green sticky plates much more than to the other tested colors. Heavy galling by O. maskelli results in premature shedding of the leaves, soon after the emergence of the wasps. Among the 84 eucalyptus species tested, the following 14 species were found to be suitable hosts: E. botryoides, E. bridgesiana, E. camaldulensis, E. cinerea, E. globulus, E. grandis, E. gunii, E. nicholii, E. pulverulenta, E. robusta, E. rudis, E. saligna, E. tereticornis and E. viminalis. This study focused on morphological and development characters that can clearly distinguish O. maskelli from Ophelimus eucalypti Gahan, and on examining the effect of crossing between eucalyptus species on the development possibilities of the wasps. Also considered were the effect of the food

关键词： breeding systems   fruit production   hemiepiphytic cactus   Hylocereus undatus   pollination biology   Tehuacan-Cuicatlan Valley  

摘要： Nearly 118 cacti species have been used by Mesoamerican people since pre-Columbian times, and about 40 of those species show signs of domestication. Among used and domesticated species, the hemiepiphytic cactus Hylocereus undatus is one of the most appreciated in Mexico because of its ornamental value and its edible fruits which are consumed at both regional and national scales. This study analysed the pollination biology of cultivated plants of H. Undatus to determine the role of selfing in fruit production and the relative importance of nocturnal and diurnal flower visitors in cross-pollination. Flowers were open nearly 17h. Nocturnal visitors produced significantly higher fruit production (76.9%) than diurnal visitors (46.1%). During the night, nectar-feeding bats Leptonycteris curasoae and Choeronyeteris mexicana pollinate flowers, whereas during the day the bee, Apis melfera pollinates flowers. Both self-pollination (100% in unmanipulated treatments and 53.8% in hand self-pollination treatments) and hand cross-pollination treatments (40%) set fruit. The capability of selfing in this cultivated plant has not been reported elsewhere and may be a result of intense local cultivation of this plant in Mexico. This self-pollination capability may significantly reduce labor costs associated with cultivation and allow fruit production to become a viable economic option for local people. (c) 2006 Elsevier Ltd. All rights reserved.

关键词： land plants   charophycean green algae   bryophytes   lycophytes   monilophytes   gymnosperms   comparative genomics   Physcomitrella patens  

摘要： Current phylogenetic studies indicate that the closest relatives to land plants are among the charophycean green algae, which have a gametophyte-dominant life cycle and lack a multicellular sporophyte generation. Land plants evolved a multicellular sporophyte generation and organs with complex tissue and cell differentiation. A number of genes in nonflowering plants homologous to the developmental genes in flowering plants have been isolated, and their roles during evolution have been hypothesized from expression patterns. Genetic manipulation is necessary to show the gene function implicated by expression patterns. In addition to studies in established model organisms, such as Physcomitrella patens, the development of genetic manipulation techniques in more taxa should be addressed. Genomics has accelerated the identification of genes and enabled the determination of the presence/absence of homologous genes, which would be the basis for the detection of gene losses and acquisitions. The process of phenotypic evolution should ultimately be explained by gene acquisitions and losses and changes in gene functions.

关键词： carbohydrate metabolism   pathogen infection   photosynthesis  

摘要： Phytopathogen infection leads to changes in secondary metabolism based on the induction of defence programmes as well as to changes in primary metabolism which affect growth and development of the plant. Therefore, pathogen attack causes crop yield losses even in interactions which do not end up with disease of, death of the plant. While the regulation of defence responses has been intensively studied for decades, less is known about the effects of pathogen infection on primary metabolism. Recently, interest in this research area has been growing, and aspects of photosynthesis, assimilate partitioning, and source-sink regulation in different types of plant-pathogen interactions have been investigated. Similarly, phytopathological studies take into consideration the physiological status of the infected tissues to elucidate the fine-tuned infection mechanisms. The aim of this review is to give a summary of recent advances in the mutual interrelation between primary metabolism and pathogen infection, as well as to indicate current developments in non-invasive techniques and important strategies of combining modern molecular and physiological techniques with phytopathology for future investigations.

关键词： 淡紫拟青霉   生物学特性   发酵条件   木薯加工废水   植物根结线虫  

摘要： 植物根结线虫对许多经济作物造成严重的危害，可导致作物大幅减产。对于植物线虫的防治，历来以化学药剂为主，而化学药剂带来的负面影响，使得生物防治的研究成为热点。淡紫拟青霉[Paecilomyces lilacinus（Thom.）Samson]是植物线虫的重要天敌，在国内外已有开发的商品制剂。我国虽有多年的研究历史，但至今尚无比较成功的商品制剂注册。本研究在前人工作的基础上完成了以下几个方面的内容： 对淡紫拟青霉菌株E7的发酵生物学特性的研究，结果表明：它能在温度范围10℃～37℃生长，40℃未见生长迹象，其中最适宜生长的温度为28℃。菌株E7液体发酵是适宜C／N比为8：1，产孢量和发酵生物量能维持在较高水平。液体发酵初期低碳源浓度有利于产孢，后期高浓度碳源产孢数量多，要提高发酵效率，碳源浓度宜在0.7mol／mL。菌株对不同的碳源和氮源种类利用能力不同，结构复杂的碳源（可溶性淀粉和几丁质）和有机氮源（蛋白胨）有利于产孢和菌丝生长。 通过单因子和正交试验对淡紫拟青霉E7产几丁质酶、蛋白酶和产孢的条件进行了研究，试验结果表明：利用3％大豆粉、2％几丁质、微量元素0.001％硫酸锰为基本的培养基，在5％的接种量条件下产几丁质酶、蛋白酶以及产孢量均能达到高水平。50L发酵罐条件考察，基本明确了发酵过程中在12h后需氧量大大提高，需要调整通气量和转速保证容氧量，发酵终点的最适期应该在42h前后，产孢量可达到3×10～9个／mL。研究以木薯淀粉废水作为培养基发酵淡紫拟青霉E7，结果表明：在木薯加工废水中加入0.4％的尿素，和0.02％的MgSO4便可用于培养本菌株，4d产孢量达到4.96×10～8个／mL。 该菌对南方根结线虫有很好的控制效果。经该菌处理后的南方根结线虫卵孵化率大大降低，对卵的相对寄生率达到40％左右。对根结线虫盆栽试验防效超过70％；小区试验防效在50％左右；田间试验防效也在70％以上，有的超过80％。虽然不同地区防治效果有一定的差别，但仍值得研究推广。

关键词： 似血杜鹃   保护生物学   保护植物   生存状态   群落结构   繁殖生物学   保护策略   地理分布  

摘要： 似血杜鹃作为大理苍山特有的国家二级保护植物，我国特产的著名观赏花木，是杜鹃属中的珍贵种质资源，对育种很有价值。但其基础生物学资料却几近为零，亟待研究。本论文主要通过对该物种野外生存状态、生态环境、群落结构、繁殖生物学等关键环节的研究，评估其濒危现状及探讨可能的濒危原因，从而初步提出该物种的保护对策和建议。主要研究结果如下： 1．地理分布及生境： 目前似血杜鹃仅分布于大理苍山大黑顶至洗马塘海拔为3400-3700米的区域，由于分布范围狭窄，群体与群体间相距又不超过10米，难以对似血杜鹃进行居群划分。调查中只有一个居群存在。似血杜鹃分布区域为典型的高山气候，具有温度低，湿度大，风力强劲的特点，周围植物群落也体现出适应高山气候的特征。 2．群落特征： 似血杜鹃所在群落生物多样性丰富，共记录到隶属于40个科67属的96种植物，其中杜鹃花科植物无论从种类还是数量上都占有优势。从垂直结构看，该群落分层明显，灌木层占优势，是典型的苍山冷杉林上缘群落。似血杜鹃所在群落区系成分分析表明，其主要为世界分布和北温带分布，尤其是北温带分布成分占优势，表现出明显的温带特征。 3．繁殖生物学野外对似血杜鹃进行套袋实验，结果表明似血杜鹃为虫媒传粉，不进行风媒传粉，无自交和孤雌生殖。但花蕾由于昆虫捕食或腐烂病变的原因往往无法顺利开花，只有23.3％的花蕾可以顺利开花。由于开花受到阻碍，每一植株结果率均较低。成熟果实中种子呈薄片状，胚结构不明显，在萌发实验中萌发率极低。 似血杜鹃具有发达的无性繁殖能力，一株母株可以由地下发出数量不等的匍匐茎，并形成不定根和新芽苗，从而形成一个新植株，但仍与母株连在一起，新植株常可生长到与母株相同的高度，逐渐形成成片的群体。 4. 与血红杜鹃的异同在苍山海拔3400米以下的区域有大量与似血杜鹃高度相似的血红杜鹃分布，对血红杜鹃的生境，群落，外部形态，分布范围进行调查，发现两者分布范围完全无交叉，其他各方面也有较多差别。 5．濒危原因及保护策略似血杜鹃开花期花朵很容易腐败，严重影响其有性繁殖过程，但植株其他部分未见有明显病变影响。另外，昆虫对叶和花朵捕食严重，尤其对花蕾捕食，严重影响了其有性繁殖的顺利进行，对其造成了胁迫。似血杜鹃的种子有不育现象，这更进一步使得似血杜鹃的有性繁殖过程缺失，针对以上特点了对该物种的保护策略及措施。

关键词： 内生菌根真菌   分离   鉴定   抑菌活性   分子生物学  

摘要： 随着人们对药用植物内生菌根真菌研究的深入，越来越多的药用植物内生菌根真菌的次生代谢产物被分离鉴定，并被证明其中含有与宿主植物相同或相似的有效成分。研究药用植物内生菌根真菌的活性成分、为药用植物资源寻找合理的替代品已成为当今药用植物研究的热点问题之一。本实验通过对药用植物内生菌根真菌的研究，为其成为药用植物合理的替代品提供了基础数据。 本实验利用组织分离的方法，从常见的16种药用植物的根部分离得到了11株内生菌根真菌。并对其中的5个菌株进行了生物学特性、抑菌活性、有效化学成份及分子生物学等方面了研究。 供试的5个菌株分别为：分离自桔梗中的内生菌根真菌JG1102，分离自防风中的内生菌根真菌FF0121，分离自苦参中的内生菌根真菌KS1220，分离白玉竹中的内生菌根真菌YZ1104，分离自黄芩的内生菌根真菌HQin0116。其中，可以通过形态学，即分生孢子的形态特征进行鉴定的有4株。即桔梗内生菌根真菌JG1102初步鉴定为桔梗链格孢(Alternaria platycodonis)，防风内生菌根真菌FF0121根链格孢(Alternaria radicina)，苦参内生菌根真菌KS1220豆链格孢(Alternaria azukiea)，玉竹内生菌根真菌YZ1104初步鉴定为燕麦镰孢菌(Fusarium avenaceum) 本实验分别从5种不同的碳源和氮源中，筛选出适宜菌株JG1102、FF0121、KS1220、YZ1104和HQin0116生长的碳源和氮源。综合实验结果，并本着节约成本的原则，我们分别选择了葡萄糖和马铃薯作为内生菌根真菌培养中的最佳碳源和氮源，即在供试的内生菌根真菌的培养中，利用马铃薯葡萄糖(PDA)培养基就可以达到最佳的效果。在最适生长温度的研究中，本实验确定了20～25℃为内生菌根真菌的最适温度。 从供试的5个菌株中筛选出了3株具有抑制细菌活性的菌株，分别为JG1102、YZ1104和HQin0116。抑菌结果表明，此3个菌株的发酵产物、甲醇提取液、乙醇提取液对细菌均有一定的抑菌活性，并且甲醇提取液的抑菌率较乙醇提取液的抑菌率略高。但这3个菌株的水提液对测试细菌则都没有抑菌活性。 通过薄层层析色谱的分析，分别用黄酮展开剂CHCl∶MeOH(8.5∶1.5)和生物碱展开剂CHCl∶MeOH(7∶1)(加少量氨水和二乙胺)薄层展开后，10％的浓硫酸显色，观察荧光和显色斑点。结果表明：菌株JG1102、YZ1104和HQin0116与其宿主原植物含有相同或相似生物碱和黄酮类的有效成分。 以ITS1和ITS4为引物，对KS1220的rDNA进行了PCR扩增，并对扩增产物进行了测序，结果表明：这种内生菌根真菌与已有的土壤真菌的同源相似性较高。 本文的创新点： 本实验首次采用组织分离和形态学鉴定的方法，确定了桔梗内生菌根真菌JG1102为桔梗链格孢，防风内生菌根真菌FF0121为根链格孢，苦参内生菌根真菌KS1220位为链格孢，玉竹内生菌根真菌YZ1104为燕麦镰孢菌。 本实验首次筛选出了3株具有抑制细菌活性的内生菌根菌株，分别为桔梗内生菌根真菌JG1102(桔梗链格孢)、玉竹内生菌根真菌YZ1104(燕麦镰孢菌)和黄芩内生菌根真菌HQin0116。并通过化学成分的初步检验，证明了这3个菌株与其宿主原植物含有相同或相似的生物碱和黄酮类有效成分。

ISBN: (纸本)9787301107881

关键词： 青檀   繁殖生物学   种群生态学   保护策略  

摘要： 青檀(Pteroceltis tatarinowii Maxim )隶属于榆科(Ulmaceae)青檀属(Pteroceltis),是我国特有纤维树种,具有较高的经济利用价值。由于其自身的生物学和生态学特性以及人为的过度利用,近年来其种质资源急剧减少,分布区日益缩小,已被列为国家三级珍稀保护植物。然而,目前国内外关于该物种保护生物学的研究几乎还是空白,基于此,本文从形态解剖学、繁殖生物学、种群大小级结构、种群分布格局几个方面对其进行了初步研究,旨在为青檀这一珍稀濒危植物致濒原因的揭示和有效保护提供科学的依据。其研究结果如下: 1.青檀种子为休眠种子,种子质量不高,其潜在萌发率很高,可达86.7%,而实际萌发率仅为19.2%。其实际萌发率下降的实验结果与在野外调查中发现的青檀实生苗很少的现象一致。青檀种子在自然条件下较低的萌发率可能是由于种皮的限制和土壤微生物的影响所致。 2.引起青檀种子休眠的主要原因是:种子本身含有发芽抑制物和存在生理后熟现象,用质量浓度为300mg/l的赤霉素溶液浸种24h或低温层积后用赤霉素处理均能在一定程度上解除休眠促进萌发,其中以低温层积25d后用500mg/l的赤霉素浸种36h效果最好,发芽率和发芽势分别达到83.5%和65%。 3.以青檀的叶片为实验材料进行愈伤组织的诱导及快速繁殖实验,用不同浓度的NAA和6-BA对其外植体进行实验,结果表明:在MS+NAA0.5+6-BA1.0培养基上对叶片的诱导效果最佳;所设的不定芽诱导培养基效果不理想;NAA对青檀诱导生根的效果非常显著。 4.青檀在叶的解剖结构方面对干旱的石灰岩生境具有良好的适应性特征,其中生境条件最差的巢湖银屏山居群青檀的耐旱性最强,具体表现为:叶片厚,表皮细胞小,具有较厚的表皮细胞外壁和角质层;栅栏组织发达,细胞排列紧密;气孔小且密度大,成簇分布等特征。这些都是对不利环境长期适应的进化结构。 5.安徽琅琊山森林公园青檀种群结构可分为衰退型和成熟型2种类型,幼苗极少,大树也不多,种群主要集中在小树和中树阶段,总体表现为衰退趋势;不同样地青檀种群分布格局总体上为集群分布;不同发育阶段种群分布格局有所差异,总体上有集群分布向随机分布、聚集度高向聚集度低变化的趋势,不同区组对青檀空间分布格局产生影响;这种差异与其自身的生物学和生态学特性及物种间的竞争排斥作用有密切关系; 6.从研究结果来看,生境条件恶劣、幼苗在草本层的竞争中处于劣势、新植株生成困难等原因致使青檀种群天然更新困难、生存状况不佳、呈衰退的演化趋势,加之外界干扰破坏(主要是人为的干扰),不但直接造成种群内青檀数量的减少,而且导致其生境的片段化和生态环境的恶化,加重了青檀的濒危趋势。根据目前青檀的生存状况,可采取加强宣传教育力度,实施就地保护、移栽植物园等方式迁地保护等措施。同时可加强对其生理学、遗传多样性、种子库的结构和动态等方面的研究工作,以期从根本上达到对该种的保护。