Mikromorphologie der Samenschalen und Taxonomie derCactaceae: Ein raster-elektronenmikroskopischer Überblick

Micromorphology and surface sculpture of seed-coats of about 900 species ofCactaceae out of 120 genera (sensuBackeberg 1976) were examined by light and scanning electron microscopy. A survey of the seed coat characteristics (forms of testa cells, wall sculpturings, cuticular fold patterns etc.) is given. A terminology for the taxonomic application of these microstructures is proposed and their taxonomic significance is discussed.

     

Growth Conditions in In Vitro Culture Can Induce Oxidative Stress in <Emphasis Type="Italic">Mammillaria gracilis</Emphasis> Tissues

In vitro propagated plants of Mammillaria gracilis Pfeiff. (Cactaceae) develop calli without any exogenous growth regulators. This habituated tissue spontaneously regenerates morphologically normal as well as hyperhydric shoots. In this study, a possible involvement of activated oxygen metabolism in habituation and hyperhydricity in in vitro propagated plants of Mammillaria gracilis Pfeiff. (Cactaceae) was investigated. Significantly higher malondialdehyde (MDA) and carbonyl contents as well as hydrogen peroxide (H₂O₂) production were observed in habituated callus (HC), hyperhydric regenerated shoots (HS), and tumors (TT) in comparison to normal regenerated shoots (NS). Lipoxygenase (LOX) activity showed a similar trend, with a clear increase in activity in HC and HS. The activities of antioxidative enzymes, namely, peroxidase (POX), ascorbate peroxidase (APX), and catalase (CAT), were also higher in HC, HS, and TT, whereas an increase in superoxide dismutase (SOD) activity was observed in HC and HS. The majority of antioxidative isoenzymes were common to all cactus tissues, although a few tissue-specific bands were noticed. Significant decreases in phenylalanine ammonia lyase (PAL) activity, total phenolic content, and lignification were found in HS, HC, and TT in comparison to NS. Our results showed the appearance of a prominent oxidative stress in HC, HS, and TT as well as a strong induction of the antioxidant system indicating that activated oxygen metabolism could be involved in habituation and hyperhydricity and linked to the loss of tissue organization in M. gracilis. B. Balen and M. Tkalec contributed equally to this work.     

Second generation experimental hybridizations in theEchinocereus ×lloydii complex (Cactaceae), and further documentation of dioecy inE. coccineus

Artificial second generation and backcross hybrids involvingEchinocereus dasyacanthus (Texas rainbow cactus),E. coccineus (a species of claret-cup cactus), andE. ×lloydii (Lloyd's hedgehog cactus) were examined for morphological and reproductive characteristics. The hybrids grew from seed to flower in about four years, and they exhibited high fertility as measured by pollen stainability, crossability, and fruit-set. A rare breeding system inCactaceae, dioecy, was further examined inE. coccineus, using field and controlled pollination tests. Functional dioecy was documented forE. coccineus in Trans-Pecos Texas. All results suggested thatE. ×lloydii in eastern Pecos County, Texas, is a complex and dynamic population probably comprising first and later generation hybrids, including backcross hybrids. The experimental hybridizations also tended to support the occurrence of introgression into both putative parental species.     

Stomatal types ofCactaceae

The stomatal types (i.e. the arrangement of epidermal cells in the vicinity of a stomatal pore in superficial view) have been examined in more than 150 taxa ofCactaceae, mostly using documented material. Preparations have been made by mazerating pieces of tissue with modified Jeffrey's Solution and staining with chlore-zinc-jodine.—The examined members of the subfamilyCactoideae showed parallelocytic stomata with only minor deviations in a number of cases. Members of the subfamiliesPereskioideae andOpuntioideae show parallelocytic stomata on the leaves, but the stomatas of the stem represent a different type, which apparently is not yet described. It is termed opuntioid here. In most cases the stomata are superficial but a few taxa show markedly sunken or hidden stomata.—In taxa of the subfamiliesPereskioideae andOpuntioideae the stomata are generally oriented parallel to the stem axis with only minor deviations. The stomata of taxa of the subfamilyCactoideae do in general not show a particular orientation with the notable exception of a number of epiphytic genera from the tribeHylocereeae.—The results of these investigations in general coincide well with the generic classification of theCactaceae byHunt (1967). A few cases where stomatal characters suggest a differing classification merit further investigations.—Additionally, the possibilities to distinguish between paracytic and parallelocytic stomata are discussed and an amended definition for the latter is given.     

Coloured Pollen in Cactaceae: a Mimetic Adaptation to Hummingbird-Pollination?

Pollen of 361 species from 71 genera of Cactaceae was investigated for this study of the correlation between pollen colour and the pollination syndrome. 11% of all species studied had red or brown pollen, and nearly all of these species were ornithophilous. This suggests that pollen colour probably is part of the bird-flower syndrome of Cactaceae. Possibly the red or brown pollen might be a crypto-mimetic adaptation to the dark coloured bill of the pollinating hummingbird (Trochilidae) and secures safe transport to a receptive stigma without being removed by the bird immediately. The results are discussed against a background of studies encompassing about 900 species from 77 families, which provide further evidence for the proposed adaptive significance of palynological characters.     

Selenicereus wittii (Cactaceae): An epiphyte adapted to Amazonian Igapó inundation forests

The biology, ecology, and distribution ofSelenicereus (Strophocactus)wittii, one of the least known taxa ofCactaceae, are described. This epiphyte climbs appressed to tree trunks with leaf-like, flattened stems and is found exclusively along the high waterline of black water rivers (Rio Negro, Vaupés, Apaporis) in the Igapó inundation forests of Amazonia. Ecophysiologically,S. wittii is a crassulacean acid metabolism (CAM) plant. It bears white, nocturnal flowers 25 cm in length which emit a fragrance consisting mainly of benzylalcohol, benzyl benzoate, and benzyl salicylate. They exhibit an extreme sphingophilous syndrome as an adaptation to pollination by probably only two species of hawkmoth from the generaAmphimoena andCocytius. The seeds, aberrant for the family, contain air-filled chambers and are water-dispersed. Thus,S. wittii represents the paradoxical life form of an hydrochorous epiphytic cactus which withstands periodical inundation.Dedicated to emer. Univ.-Prof. DrFriedrich Ehrendorfer on the occasion of his 70th birthday     

The cactus mealybugHypogeococcus festerianus [Hem.: Pseudococcidae] an agent for the biological control ofEriocereus martinii [Cactaceae] in Australia

The mealybugHypogeococcus festerianus (Lizer y Trelles) infests cacti in Northern Argentina and Paraguay, causing deformed and distorted growth of attacked plants. Laboratory studies and field observations demonstrate that it will only infest plants in the sub-familyCereanae of theCactaceae. Its liberation in Queensland, Australia, for the control ofEriocereus spp., was approved in October 1974, and it has since established widely.

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Résumé La cochenille farineuseHypogeococcus festerianus (Lizer y Trelles) infeste les cactus dans le nord de l’Argentine et le Paraguay, causant chez ces plantes, des déformations et une croissance anormale. Les observations faites dans la nature et en laboratoire montrent qu’elle s’attaque exclusivement aux plantes de la sous-famille desCereanae de la famille desCactaceae. Son introduction en Australie a été approuvée en octobre 1974, et elle s’est largement établie depuis.

     

Eriocereophaga humeridens [Col.: Curculionidae], a potential agent for the biological control ofEriocereus martinii [Cactaceae] in Australia

The weevilEriocereophaga humeridens O'Brien attacks the cactusEriocereus adscendens (Gurke) in N.E. Brazil. Laboratory tests and field observations demonstrate that it will also acceptEriocereus martinii Lab. as host, and does not damage plants except in the sub-familyCereanae of theCactaceae. Young plants and regrowth are preferentially attacked and larval feeding inE. martinii results in the death of attacked stems.E. humeridens was approved for liberation in Queensland, Australia in February 1976, for the control ofEriocereus spp., and field releases were made in 1976.

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Résumé Le coléoptèreEriocereophaga humeridens O'Brien attaque le cactusEriocereus adscendens (Gurke) qui est indigène du Nord-Est du Brésil. Il a été établi par des essais en laboratoire ainsi que par des observations en champ d'expérimentation, qu'E. humeridens peut également vivre surEriocereus martinii Lab., et qu'il n'est nuisible que pour les plantes de la sous-familleCereanae desCactaceae. Il attaque de préférence les jeunes pousses et les rejetons; et ses larves tuent en les mangeant les tiges d'E. martinii qui sont atteintes. En février 1976, afin de limiter les espèces d'Eriocereus, l'approbation fut donnée de lacherE. humeridens en Queensland, Australie, ce qu'on a fait sur les lieux au cours de la même année.

     

Stigma morphology in Aylostera subg. Mediolobivia (Cactaceae) and its importance for systematic investigation

The stigma of 31 taxa of Aylostera (Cactaceae) was studied using environmental scanning electron microscopy. Seven stigma types could be defined, based on the degree of fusion of the stigmatic lobes and, when these are completely separated (types I and II), their orientation. Four types (types IV, V, VI and VII) are present only in Aylostera subg. Mediolobivia, two of which (types IV and VII) are species-specific. Stigma morphology was found to be a good diagnostic character in Aylostera subg. Mediolobivia, allowing in some cases to distinguish species that had been confused previously. The stigmatic types here defined seem apt to characterize natural groups within the subgenus and are useful as an aid for species identification and the characterization of new taxa.     

Epilithic plant communities on inselbergs in French Guiana

Abstract. Tropical inselbergs are isolated elevations with a special type of vegetation and surrounded by rain forest. The paper describes, using the field methods of Braun-Blanquet, combined with numerical analysis (clustering, Correspondence Analysis), plant communities on French Guianan inselbergs. Six new associations are described: Portulacetum sedifolii, Furcraeetum foetidae, Ananasetum annassoidis, Stylosanthetum guianensis, Axonopetum ramosi and (endemic to the Guianan inselbergs) Pepinietum geyskesii – with three subassociations. The six vegetation units reflect different combinations of environmental factors such as local relief, insolation, water availability and soil depth. All syntaxa show a low species diversity. Species of Cyperaceae, Poaceae, Lentibulariaceae and Bromeliaceae are predominant, whereas families typical of other South American inselbergs (Velloziaceae and Cactaceae), are missing or scarce. Similarities between vegetation units of South American and African inselbergs are emphasized.     

Investigations onAlcidion cereicola [Col.: Cerambycidae] a potential agent for the biological control ofEriocereus martinii [Cactaceae] in Australia

The CerambycidAlcidion cereicola Fisher attacks cacti in northern Argentina, the larval feeding resulting in the death of mature plants. The insect is hardy and easily reared, with a short life cycle. Laboratory tests and field observations demonstrate that it will only damage plants in the sub-familyCereanae of theCactaceae. It was approved for liberation in Queensland, Australia, in October 1974 for the control ofEriocereus martinii Lab.

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Résumé Le longicorneA. cereicola Fisher ataque les Cactus d'Argentine septentrionale, les larves provoquant la mort des plantes adultes. L'insecte est robuste et facile à élever, ayant un cycle biologique de courte durée. Les observations faites en laboratoire et dans la nature montrent qu'il s'attaque exclusivement aux plantes de la sous-familleCereanae de la famille des Cactacées. Son introduction en Queensland, Australie a été approuvée en Octobre 1974 pour la lutte contreEriocereus martinii Lab.

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FormerlyCruttwell.     

Osmotic values of some plant species from Cuba

The authors give measurements of osmotic values in 35 Cuban plant species, using the cryoscopic method. Osmotic values of plants correspond relatively well with environmental conditions, but in different species of the same habitat they may be different. The lowest values were found inCactaceae (?1.6 to ?6.2 atm.) and in epiphyticBromeliaceae (?4.6 to ?4.7 atm.), the highest in halophytes: ?21 to ?56 atm.     

ACactoblastis [Lep.: Phycitidae] for the biological control ofEriocereus martinii [Cactaceae] in Australia

ACactoblastis sp. was found on Harrisia cactus (Eriocereus martinii Lab.) in north-eastern Argentina. In biology and life history it is similar toCactoblastis cactorum (Berg.) though attacking different cacti. Laboratory tests and field observations demonstrate that it will only damage plants in the sub-tribeCereanae of theCactaceae. It was approved for liberation in Queensland, Australia in August 1975 for the control ofEriocereus spp., and field releases were made in October 1978.     

两种方法形成菌丝球固定2-氯酚降解菌的对比

【目的】系统研究吸附法和同时培养法对所形成混合菌丝球的外观形态、内部结构及其去除2-氯酚效果的影响。【方法】采用吸附法和同时培养法将可降解2-氯酚的光合细菌PSB-1D固定在黄孢原毛平革菌(Phanerochaete chrysosporium)DH-1发酵而成的菌丝球上,形成混合菌丝球。以单一菌丝球为对照,利用光学显微镜、扫描电镜等仪器观察混合菌丝球的外观形态和内部结构,考察2种方法对混合菌丝球成球效果的影响;以无菌培养液为空白对照,考察游离光合细菌、单一菌丝球、2种方法形成混合菌丝球对2-氯酚的降解效能。【结果】在吸附法形成的混合菌丝球上,光合细菌主要集中在过渡区;而同时培养法将光合细菌牢固地包埋在菌丝球内核区,并大量簇状附着生长在菌丝交联的空隙处和每根菌丝上。在接种等量孢子和光合细菌的前提下,同时培养法较吸附法操作时间更短,成球数量更多,形成菌丝球干湿比更大,单位菌丝干重上固定的细菌数量更多。菌丝球降解体系和游离光合细菌对2-氯酚的降解均符合一级动力学特征。同时培养法形成的混合菌丝球降解效果最好,7 d内对初始浓度为50 mg/L的2-氯酚降解率可达89%以上,降解速率常数为0.3286 mg/(L·d),2-氯酚半衰期t1/2为2.8 d。【结论】首次报道黄孢原毛平革菌包埋固定化光合细菌形成混合菌丝球。该研究为生物质固定化材料的实际应用提供理论依据。     

应用matK基因鉴别青天葵及其常见混伪品

分析了青天葵及其混伪品matK序列,以期在分子水平建立青天葵及其常见混伪品的鉴别方法。采用一对通用引物对matK基因进行PCR扩增并测序,所得序列用DNAMAN、MEGA等软件进行分析。获得青天葵及其混伪品的matK基因序列长度为587 bp,平均GC含量为32.8%。青天葵的种内遗传距离为0,与混伪品种间遗传距离范围为0.016～0.375。基于matK基因序列构建的NJ聚类树能明显地区别青天葵及其混伪品。因此,应用matK基因序列可以有效鉴别青天葵及其混伪品。     

Identification of five Orius species in Japan by multiplex polymerase chain reaction

We developed multiplex polymerase chain reaction methods to identify five Orius (Heteroptera: Anthocoridae) species that occur commonly in Japan: Orius sauteri, Orius minutus, Orius strigicollis, Orius nagaii, and Orius tantillus. The method amplified internal transcribed spacer 1 of the nuclear ribosomal DNA by using five primers simultaneously and produced species-specific banding patterns upon agarose gel electrophoresis. Reliability of the method was tested for 350 individuals of 23 strains, and consistent results were obtained. Dichotomous keys are also provided for easy and quick species identification.     

Simultaneous determination of two human urinary metabolites of N,N-dimethylformamide using gas chromatography–thermionic sensitive detection with mass spectrometric confirmation

Two human urinary metabolites of the industrial solvent N,N-dimethylformamide (DMF), N-hydroxymethyl-N-methylformamide (HMMF) and N-acetyl-S-(N-methylcarbamoyl)cysteine (AMCC), were assayed using a new analytical method (gas chromatography and thermionic sensitive detection). Clean-up of urine samples includes a liquid–liquid extraction step followed by a solid-phase extraction step to separate HMMF and AMCC from other urine components. During clean-up, AMCC is converted into ethyl-N-methylcarbamate (EMC), and during gas chromatography, HMMF is degraded in the injector to N-methylformamide (NMF). All the validation data necessary for a quantitative procedure are given. The method was applied to urine samples from workers exposed to DMF and from the general population. The results were confirmed by mass spectrometric determination. For this purpose a further liquid–liquid extraction step was introduced in the clean-up procedure. Background levels of AMCC in the general population were identified.     

Senescence of Unfertilised Flowers in Epiphyllum Hybrids

Epiphyllum hybrids served as a model for the study of reserve remobilisation from unfertilised flowers to the mother stem tissues. Early phases of the tube senescence characterised by wilting were connected with degradation and transfer of reserve substances to the somatic organs of the mother plant. The degradation process began in perianth and stamens and continued through the successive zones (receptacular, pericarpellar and pedicellar) of the flower tube. The phloem-mediated backward substance transport was naturally indicated by the red pigment of the perianth -- cactorubin, while integrity of cells and tissues and green colour of the flower tube were still preserved. For the later phases of senescence the loss of permeability and successive breaking of the cell integrity, connected with the colour change of the tube from green to red was evident. The functioning of vascular bundles especially their phloem parts conducting dissolved substances to the sinks in mother stem organs were preserved until late stages of senescence. The recycling and remobilisation of nutrients from all parts of unfertilised ovary and ovules may be considered as a part of the life strategy in the family Cactaceae as well as in other taxa evolutionarily adapted to life in extreme environmental conditions.     

Piercing and vacuum infiltration of the mature embryo: a simplified method for <Emphasis Type="Italic">Agrobacterium-</Emphasis>mediated transformation of <Emphasis Type="Italic">indica</Emphasis> rice

Traditional transformation methods are complex and time consuming. It is generally difficult to transform indica rice varieties using traditional transformation methods due to their poor regeneration. In this contribution, a simple method was developed for the transformation of indica rice. In this method, the mature embryos of soaked seeds were pierced by a needle, and then soaked in the Agrobacterium inoculum under vacuum infiltration. The inoculated seeds germinated and grew to maturation (T ₀) under nonsterile conditions. The herbicide or antibiotic analysis and molecular analysis were conducted on T ₀ plants. The results showed that although the efficiency of transformation was about 6.0%, it was easier to transform indica rice using the proposed method, and the transformation process was significantly shortened. The success of transformation was further confirmed by the genetic and molecular analyses of T ₁ transformants.