15种独蒜兰属植物叶表皮微形态特征及分类学意义研究

为解决兰科(Orchidaceae)独蒜兰属(Pleione D. Don)植物分类学问题并探索叶片超微结构在分类学中的意义,该研究利用扫描电子显微镜,对独蒜兰属15种植物成熟叶片的细胞界限、角质层纹理、气孔器分布等15个叶表皮超微特征进行观测分析,以明确它们的分类学意义。结果表明：(1)细胞界限、表皮细胞蜡质量、角质层纹理、气孔器分布、气孔器周围蜡质、气孔器外拱盖内缘、角化现象、气孔器相对高度、表皮细胞长度、表皮细胞面积、保卫细胞长度和保卫细胞面积这9个指标对于该属分类具有重要价值和意义。(2)利用上述特征可以对春花独蒜兰组(S. Humiles)、独蒜兰组(S. Pleione)和独蒜兰复合体(P. bulbocodioides complex)的组内区分进一步细化。(3)聚类分析将15种独蒜兰属植物聚类为4个分支,与传统分类学和分子系统学分类结果基本一致。研究认为,大理独蒜兰(P. × taliensis P. J. Cribb & Butterfield)与云南独蒜兰［P. yunnanensis (Rolfe) Rolfe］、黄花独蒜兰(P. forrestii Schltr.)在多个叶片微观特征方面表现出高度的一致性,大理独蒜兰的亲本有待于进一步研究确认。     

不同温度对独蒜兰开花和生长的影响

该研究采用人工温室于3种培养温度(20℃/15℃、15℃/10℃、10℃/5℃)条件下,分析独蒜兰生长开花进程以及假鳞茎中有机物质含量的动态变化。结果表明:(1)于20℃/15℃(模拟原生地开花期自然温度)处理下,独蒜兰进入初花期的时间比15℃/10℃、10℃/5℃处理下分别提前24d和53d,花期分别延长了4d和6d。(2)独蒜兰的花色以10℃/5℃处理较深,但该处理中有哑蕾出现。(3)老假鳞茎生长开花过程中,20℃/15℃处理的淀粉含量呈升高趋势,15℃/10℃和10℃/5℃处理先升高后降低;3种温度处理下,可溶性糖均在花期含量最高,且10℃/5℃处理下可溶性糖含量、可溶性蛋白含量均保持较高水平。研究认为,20℃/15℃和15℃/10℃培养温度均有利于独蒜兰的生长和开花;独蒜兰休眠的假鳞茎不需要经过低温诱导解除休眠,随着温度上升,相应的生长发育进程就会启动。     

独蒜兰

独蒜兰（Pleione bulbocodioides）为兰科独蒜兰属多年生草本植物。陆生兰,一般株高15～25 cm,多分布于中国长江流域及其以南的地区,海拔630～3 000 m的密林下或沟谷旁有泥土的石壁上常见大片野生分布。独蒜兰属植物全球约16种,中国分布有15种。根据1999年国家林业局农业部第4号令批准的《国家重点保护野生名录（第1批）》,     

广州植物两个新分布属及其地理学意义

报道了采自广州从化的野牡丹科肉穗草属（Sarcopyramis）和兰科独蒜兰属（Pleione）各一种新分布植物,分别为楮头红（S. nepalensis Wall.）和独蒜兰[P. bulbocodioides (Franch.) Rolfe],凭证标本存放于华南农业大学植物标本馆(CANT)。两种植物在从化的分布地海拔260～300 m,是二者在中国大陆的最南部、海拔最低的分布记录,对研究两属植物的扩散机制、垂直分布及气候变化对物种迁移的影响等理论问题具有参考意义。     

台湾独蒜兰假鳞茎显微及超微结构观察

以休眠期的台湾独蒜兰(Pleione formosana)假鳞茎为试材,利用石蜡切片及透射电子显微镜,分别对假鳞茎的5个部位(假鳞茎基部、假鳞茎中部、假鳞茎外侧、假鳞茎与叶芽相接处、假鳞茎与花芽相接处)进行了系统观察分析。结果发现：(1)台湾独蒜兰假鳞茎5个部位均观察到液泡及不同程度液泡化的细胞,表皮细胞覆着有厚厚的蜡质层。(2)台湾独蒜兰假鳞茎基部、中部、外侧细胞中均存在一定的叶绿体,少量线粒体分布在其周围。(3)假鳞茎薄壁细胞中存在淀粉粒及造粉体,且造粉体伴随有形成淀粉粒的现象。(4)假鳞茎基部、中部、外侧及其与花芽相接处的薄壁细胞壁之间有大量胞间连丝,筛管-伴胞复合体与薄壁细胞间也存在胞间连丝,同时细胞间存在不同形状的细胞间隙。研究结果表明,台湾独蒜兰假鳞茎发挥了其作为储水器官、光合作用场所及储存碳水化合物的功能,同时休眠期间主要以共质体途径进行物质的交换与运输。     

独蒜兰的离体快速繁殖

1植物名称独蒜兰[Pleione bulbocodioides(Ranch.)Ro1fe]. 2材料类别假鳞茎. 3培养条件芽诱导培养基:(1)VW 6-BA 0.2 mg·L-1(单位下同) NAA 0.1;增殖培养基:(2)MS 6-BA 3 NAA 0.2 活性碳(AC)1 g·L-1;生根培养基:(3)1/2 MS IBA 1.0 AC 1 g·L-1.以上培养基蔗糖浓度(1)、(2)为3.0%,(3)为2.0%;琼脂6.5 g·L-1;pH 5.2～5.4.培养温度为(25±2)℃,连续光照12 h·d-1,光照度为2000 1x.     

疣鞘独蒜兰和岩生独蒜兰的组织培养与快速繁殖

1植物名称 疣鞘独蒜兰（Pletone praecox）、岩生独蒜兰（P．saxicola）。 2材料类别 未开裂果实得到的无菌种子。     

白花独蒜兰的组织培养和快速繁殖

1植物名称白花独蒜兰(Pleione allbiflora). 2材料类别种子、原球茎. 3培养条件种子播种培养基:(1)KC[1] CM 100mg·L-1(单位下同) AC 2 g.L-1.拟原球茎诱导培养基:(2)MS NAA 1.0;(3)MS 6-BA 1.0;(4)MS NAA 1.0 6-BA 0.2;(5)MS NAA 0.2 6-BA 1.0.生根壮苗培养基:(6)Hypenox2号(N:P:K=20:20:20,美国Hyponex化学公司产品)2 g.L-1 NAA0.5 香蕉匀浆100 ml.L-1 AC 2 g.L-1.以上培养基分别附加1.5%蔗糖、0.8%琼脂,pH5.4.培养温度(25±1)℃,光照度1 000～1 500lx,光照时间14 h·d-1;种子播种后暗培养2周,再转入光下培养.     

独蒜兰种子共生萌发研究

采用从独蒜兰分离的菌根真菌与其种子在燕麦培养基上共生萌发。结果表明GN21、GN23和GN24的作用效果较好, 其中GN21萌发率84.6%, 高于对照7个百分点, 达到显著性。同时也表明, 从同一兰科植物分离到的属于同一属的不同菌根真菌种, 有的能明显促进种子萌发, 有的却不能促进萌发, 甚至产生病斑, 引起原球茎死亡。     

大理独蒜兰

<正> 大理独蒜兰(Pleione forrestii Schlechter)是Schlechter于1912年发表的新种,属兰科独蒜兰属(又名一叶兰属)植物,产于我国云南西部,岩生或地生,海拔700—3000米。模式标木为Forrest 4849,采自大理。属名Pleione系人名,为纪念Pleiades的母亲Pleione而取。笔者1992年2月20日将其种于广西桂林雁山,并于3月开花。据栽培观察,该植物先花后叶,花葶高约8cm,花黄色,花萼花瓣同     

Impact of flowering buckwheat on Lepidopteran cabbage pests and their parasitoids at two spatial scales

We assessed the potential of annual buckwheat, Fagopyrum esculentum Moench, to lead to improved parasitism of lepidopteran cabbage pests over four years. Pest, parasitism, and hyperparasitism rates were monitored in replicated cabbage plots (12 × 20 m) with or without 3 m wide buckwheat borders from 2000 to 2003. Floral borders did not significantly increase egg, larval, or pupal densities of cabbage looper, Trichoplusia ni (Hübner), imported cabbageworm, Pieris rapae (L.), or diamondback moth, Plutella xylostella (L.). Buckwheat increased parasitism rates by Voria ruralis (Fallen) on T. ni larvae and Cotesia rubecula (Marshall) on P. rapaelarvae over four years. Parasitism by Diadegma insulare (Cresson) on P. xylostella larvae was higher in buckwheat than control plots in the first year, and parasitism by Euplectrus plathypenae (Howard) on T. ni larvae was lower in buckwheat than control plots in the second year. The hyperparasitoid Conura side (Walker) attacked D. insulare all four years, but buckwheat did not affect hyperparasitism rates. The effect of spatial scale on pest densities and parasitism in 2001 was evaluated by comparing plots separated at least 67 m (nearby) versus 800 m apart (isolated). T. ni pupae and P. rapae eggs and pupae were more abundant in plots in closer proximity, whereas P. xylostella densities did not vary by the spatial separation of plots. Tachinids and Pteromalus puparum (L.) attacked more P. rapae in nearby plots. E. plathypenae responded to the treatment × scale interaction, parasitizing more in control than buckwheat when plots were isolated but not when plots were nearby.     

Evolution and phylogenetic relationships within Porinaceae (Ostropomycetidae), focusing on foliicolous species

A phylogeny of the lichen family Porinaceae using mitochondrial SSU rDNA sequences is presented, with special focus on foliicolous taxa. Fifty specimens of 28 mostly tropical species, representing eight species groups of Porina as well as the genus Trichothelium, were analysed together with species of other members of Ostropomycetidae, and using Agyriaceae as outgroup. We performed the phylogenetic analyses with a Bayesian approach and under the criterion of maximum parsimony. Four main clades can be distinguished: the P. nitidula-group s. lat. (including Trichothelium, P. papillifera and P. rubescens), the Porina epiphylla-group s. lat. (including the P. radiata-, the P. nucula-, the P. imitatrix- and the P. epiphylla-group s. str.) and two clades of the P. rufula-group. The genus Porina as understood by all recent concepts is paraphyletic, and Trichothelium is nested within the Porina nitidula-group. The non-setose P. repanda forms a monophyletic clade with Trichothelium. The tree does not support a monophyletic origin of substrate preferences or photobiont selection. Species-specific associations with morphologically different trentepohlioid photobionts mapped on the tree suggest that closely related mycobiont species switch between different types of algae.     

Phylogenetic analysis of the <Emphasis Type="Italic">lux</Emphasis> operon distinguishes two evolutionarily distinct clades of <Emphasis Type="Italic">Photobacterium leiognathi</Emphasis>

The luminous marine bacterium Photobacterium mandapamensis was synonymized several years ago with Photobacterium leiognathi based on a high degree of phenotypic and genetic similarity. To test the possibility that P. leiognathi as now formulated, however, actually contains two distinct bacterial groups reflecting the earlier identification of P. mandapamensis and P. leiognathi as separate species, we compared P. leiognathi strains isolated from light-organ symbiosis with leiognathid fishes (i.e., ATCC 25521^T, ATCC 25587, lequu.1.1 and lleuc.1.1) with strains from seawater originally described as P. mandapamensis and later synonymized as P. leiognathi (i.e., ATCC 27561^T and ATCC 33981) and certain strains initially identified as P. leiognathi (i.e., PL-721, PL-741, 554). Analysis of the 16S rRNA and gyrB genes did not resolve distinct clades, affirming a close relationship among these strains. However, strains ATCC 27561^T, ATCC 33981, PL-721, PL-741 and 554 were found to bear a luxF gene in the lux operon (luxABFE), whereas ATCC 25521^T, ATCC 25587, lequu.1.1 and lleuc.1.1 lack this gene (luxABE). Phylogenetic analysis of the luxAB(F)E region confirmed this distinction. Furthermore, ATCC 27561^T, ATCC 33981, PL-721, PL-741 and 554 all produced a higher level of luminescence on high-salt medium, as previously described for PL-721, whereas ATCC 25521^T, ATCC 25587, lequu.1.1 and lleuc.1.1 all produced a higher level of luminescence on low-salt medium, a characteristic of P. leiognathi from leiognathid fish light organs. These results demonstrate that P. leiognathi contains two evolutionarily and phenotypically distinct clades, P. leiognathi subsp. leiognathi (strains ATCC 25521^T, ATCC 25587, lequu.1.1 and lleuc.1.1), and P. leiognathi subsp. mandapamensis (strains ATCC 27561^T, ATCC 33981, PL-721, PL-741 and 554).Electronic Supplementary Material Supplementary material is available for this article at .     

Effects of the estuarine dinoflagellate Pfiesteria shumwayae (Dinophyceae) on survival and grazing activity of several shellfish species

A series of experiments was conducted to examine effects of four strains of the estuarine dinoflagellate, Pfiesteria shumwayae, on the behavior and survival of larval and adult shellfish (bay scallop, Argopecten irradians; eastern oyster, Crassostrea virginica; northern quahogs, Mercenaria mercenaria; green mussels, Perna viridis [adults only]). In separate trials with larvae of A. irradians, C. virginica, and M. mercenaria, an aggressive predatory response of three strains of algal- and fish-fed P. shumwayae was observed (exception, algal-fed strain 1024C). Larval mortality resulted primarily from damage inflicted by physical attack of the flagellated cells, and secondarily from Pfiesteria toxin, as demonstrated in larval C. virginica exposed to P. shumwayae with versus without direct physical contact. Survival of adult shellfish and grazing activity depended upon the species and the cell density, strain, and nutritional history of P. shumwayae. No mortality of the four shellfish species was noted after 24 h of exposure to algal- or fish-fed P. shumwayae (strains 1024C, 1048C, and CCMP2089) in separate trials at ≤5 × 10³ cells ml⁻¹, whereas higher densities of fish-fed, but not algal-fed, populations (>7–8 × 10³ cells ml⁻¹) induced low (≤15%) but significant mortality. Adults of all four shellfish species sustained >90% mortality when exposed to fish-fed strain 270A1 (8 × 10³ cells ml⁻¹). In contrast, adult M. mercenaria and P. viridis exposed to a similar density of fish-fed strain 2172C sustained <15% mortality, and there was no mortality of A. irradians and C. virginica exposed to that strain. In mouse bioassays with tissue homogenates (adductor muscle, mantle, and whole animals) of A. irradians and M. mercenaria that had been exposed to P. shumwayae (three strains, separate trials), mice experienced several minutes of disorientation followed by recovery. Mice injected with tissue extracts from control animals fed cryptomonads showed no response. Grazing rates of adult shellfish on P. shumwayae (mean cell length ±1 standard error [S.E.], 9 ± 1 μm) generally were significantly lower when fed fish-fed (toxic) populations than when fed populations that previously had been maintained on algal prey, and grazing rates were highest with the nontoxic cryptomonad, Storeatula major (cell length 7 ± 1 μm). Abundant cysts of P. shumwayae were found in fecal strands of all shellfish species tested, and ≤45% of the feces produced viable flagellated cells when placed into favorable culture conditions. These findings were supported by a field study wherein fecal strands collected from field-collected adult shellfish (C. virginica, M. mercenaria, and ribbed mussels, Geukensia demissa) were confirmed to contain cysts of P. shumwayae, and these cysts produced fish-killing flagellated populations in standardized fish bioassays. Thus, predatory feeding by flagellated cells of P. shumwayae can adversely affect survival of larval bivalve molluscs, and grazing can be depressed when adult shellfish are fed P. shumwayae. The data suggest that P. shumwayae could affect recruitment of larval shellfish in estuaries and aquaculture facilities; shellfish can be adversely affected via reduced filtration rates; and adult shellfish may be vectors of toxic P. shumwayae when shellfish are transported from one geographic location to another.     

中国假尾孢属的研究V

本文报导中国假尾孢属的30个种,其中有2个新种:透骨草假尾孢(Pseudocercospora phrymae),槐假尾孢(P. sophorae), 6个新组合:无花果假尾孢(P. fici),爵床假尾孢(P. justiciae),木犀生假尾孢(P. osmanthicola),海桐花假尾孢(P. pittospori),色柱假尾孢(P. polygonorum),花椒假尾孢(P. xanthoxyli)和5个中国新记录。文中对新种和新组合进行了描述并绘图,其他种作了简要描述或讨论。研究的标本保存在中国科学院微生物研究所真菌标本室(HMAS)。     

Effect of Bt-cotton expressing Cry1A(c) on the survival and fecundity of two hymenopteran parasitoids (Braconidae, Encyrtidae) in the laboratory

We examined the effect of Bt-cotton (Event 531) plants expressing the Bacillus thuringiensis δ-endotoxin CryIA(c) on two hymenopteran endoparasitoids, Cotesia marginiventris and Copidosoma floridanum. In the laboratory, parasitized and unparasitized Pseudoplusia includens larvae were reared on foliage from a conventional soybean cultivar (Pioneer 97B61), a conventional cotton cultivar (DPL 5415), or a Bt-cotton cultivar (NuCotn 33B). C. marginiventris developed significantly faster within P. includens larvae feeding on Pioneer 97B61 and DPL 5415 compared to those feeding on NuCotn 33B. C. marginiventris that developed inside P. includens larvae feeding on NuCotn 33B suffered reduced longevity, and females had fewer ova. NuCotn 33B also affected the growth and development of P. includens parasitized with C. floridanum and life history parameters of adult C. floridanum. Parasitized and unparasitized P. includens developed more slowly when they were fed NuCotn 33B and the prepupae weighed less. Survival of parasitized and unparasitized P. includens was lower when larvae were fed NuCotn 33B and some evidence points to higher susceptibility of parasitized caterpillars to intoxication by NuCotn 33B. Fewer C. floridanum adults emerged from hosts fed NuCotn 33B, but pupal weight and adult longevity were unaffected. Analysis comparing the two experiments conducted with C. floridanum suggests that older NuCotn 33B plants (90–120 days after planting) may affect parasitoid development and adult survival less than younger NuCotn 33B plants (60–90 days after planting). Feeding on NuCotn 33B by P. includens affected the survival and development of the two hymenopteran endoparasitoids studied here, and the degree of the effect was similar to that observed with natural resistance found in soybean plants. It remains to be determined if the effects demonstrated here are less than, equal to, or greater than the impact of conventional insecticide applications used in conventional, non-transgenic, cotton.     

瓜实蝇2种蛹寄生蜂生防潜能比较

[目的] 比较研究蝇蛹俑小蜂与蝇蛹金小蜂对瓜实蝇的控制潜能。[方法] 采用非选择性实验测定蝇蛹俑小蜂与蝇蛹金小蜂对瓜实蝇蛹的寄生效能、繁殖能力,并研究覆土厚度对2种寄生蜂寄生效能的影响。[结果] 2种寄生蜂对瓜实蝇的寄生率无显著性差异,但蝇蛹金小蜂的平均单雌产后代数比蝇蛹俑小蜂的多,分别为30和23头。土壤厚度显著影响2种寄生蜂的寄生效能,随着土壤厚度的增加,2种寄生蜂对瓜实蝇蛹的寄生率均显著下降,但蝇蛹金小蜂的寄生率下降更为迅速;蝇蛹俑小蜂最深可寄生8 cm土壤下的瓜实蝇蛹,而蝇蛹金小蜂在土壤厚度达到3 cm时就不能完成寄生。[结论] 蝇蛹俑小蜂较蝇蛹金小蜂更适合应用于瓜实蝇蛹的生物防治。     

秦岭芍药属植物及其地理分布修订

在野外调查的基础上,结合查阅标本和文献比对,对秦岭地区芍药属(Paeonia)植物及其地理分布进行修订。结果表明,秦岭地区分布有芍药属8个野生种及1个栽培种,可分为牡丹组(Section Mouton DC.)和芍药组(Sect. Paeonia)。地理分布格局研究表明：芍药组内4个种：草芍药(P. obovata)、美丽芍药(P. mairei)、芍药(P. lactiflora)、川赤芍(P. anomala subsp. veitchii)和牡丹组中的牡丹(P. suffruticosa Andrews)、紫斑牡丹(P. rockii)为秦岭广布种,卵叶牡丹(P. qiui)和杨山牡丹(P. ostii)为秦岭中东部分布种,矮牡丹(P.jishanensis)为秦岭东部分布种。根据修订,给出了秦岭地区芍药属植物分种检索表。     

油菜类型和品种对外来入侵杂草小子虉草的替代控制作用

外来入侵植物小子虉草（Phalaris minor Retz.）是世界公认的冬季农田恶性杂草,掌握农作物对其替代控制作用具有重要的研究价值。前期研究表明,油菜是替代控制小子虉草的优良农作物,然而,目前尚不清楚油菜类型与品种对其控制能力的影响。为此选取与小子虉草同域发生的不同类型（白菜型油菜、芥菜型油菜和甘蓝型油菜）油菜品种各3种,通过田间小区实验和室内化感作用测定,对比研究其对小子虉草的生长、繁殖、表型以及化感作用的影响。田间实验显示：竞争方式（种内或种间竞争）和油菜类型对小子虉草的地上生物量、种子数、株高、分枝数、叶面积和比叶面积存在极显著（P=0.0001）影响;而油菜品种对小子虉草的地上生物量（P=0.6064）、种子数（P=0.3577）、株高（P=0.4279）、分枝数（P=0.6357）、叶面积（P=0.8839）和比叶面积（P=0.3424）均无显著影响。3种类型油菜对小子虉草生长、繁殖以及表型的影响存在明显差异,其中芥菜型油菜对小子虉草的上述指标的影响最强,而白菜型油菜的影响最弱。室内生物测定显示,油菜对小子虉草具有化感抑制作用,当供试油菜叶片水提液浓度为0.1 g/mL时,小子虉草种子的萌发和幼苗的株高、根长、生物量均被显著抑制;研究也表明不同类型油菜对小子虉草的化感作用显著不同,同等条件下,芥菜型油菜对小子虉草的化感抑制作用最强。综上所述,油菜类型对外来入侵小子虉草的控制作用存在显著差异,其中芥菜型油菜对植物小子虉草的替代控制作用明显优于白菜型油菜和甘蓝型油菜,而其强的化感抑草特性或许是其强控草能力的原因之一。另外,本研究也为进一步利用油菜替代控制入侵植物小子虉草提供了参考。     

Domoic acid production by Pseudo-nitzschia australis and Pseudo-nitzschia calliantha isolated from North Chile

The morphology and toxicity of the four ubiquitous species belonging to the genus Pseudo-nitzschia found in mixed blooms of phytoplankton from northern Chilean waters were studied. The phytoplankton samples and cultures obtained were identified by scanning electron microscopy, revealing the presence of Pseudo-nitzschia australis, P. calliantha, P. pseudodelicatissima and P. subfraudulenta. This is the first report of P. calliantha in northern Chile. Toxin analyses using the LC–MS method confirmed the presence of domoic acid in P. australis and P. calliantha. Domoic acid was not detected in cultures of P. subfraudulenta. This study therefore confirms P. australis and P. calliantha as an unequivocal source of domoic acid in Chilean waters. P. australis is probably the most important producer of amnesic shellfish toxin in view of its domoic acid content. However, more research is needed to evaluate the potential for toxin production in P. pseudodelicatissima.