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1.
Abstract

Interpopulational, interspecific comparison of the habitats, structural features, and distribution of Tomenthypnum in North America and eastern Asia indicate that T. falcifolium and T. nitens are present in both areas. The Chinese populations occur in habitats similar to North American T. falcifolium. Statistical and multivariate analyses of seven characters indicate that the Chinese populations are intermediate with, but distinct from the North American populations of T. nitens and T. falcifolium. We conclude that taxonomically, the Chinese populations belong within the concept of T. falcifolium, and when further collections are known from eastern Asia, may belong to a geographically isolated subspecific taxon.  相似文献   

2.
《Journal of bryology》2013,35(1):129-132
Abstract

Being a synonym of Bryum nitens Hook., B. cruegeri Hampe is not new to Africa. In addition to tubers, deciduous shoot tips and shoot fragments act as vegetative propagules.  相似文献   

3.
《Journal of bryology》2013,35(3):525-529
Abstract

Leiocolea rutheana is reported new to Ireland. Surface water. chemistry data and species releves are presented and it is suggested that L. rutheana is an addition to the list of Boreal relict species in Ireland.  相似文献   

4.
The egg parasitoid Anaphes nitens (Hymenoptera: Mymaridae) parasitizes the Eucalyptus snout-beetle Gonipterus platensis (Coleoptera: Curculionidae), one of the main defoliating beetles of Eucalyptus. Outbreaks of this pest are being recorded in areas with low parasitism rates by A. nitens. Endosymbiont bacteria can affect the reproductive characteristics of host insects increasing or decreasing the parasitism rate. The objectives of this study were to identify the presence, phylogeny and transmission modes of endosymbiont bacteria in A. nitens and G. platensis. Six populations of A. nitens and one of G. platensis were evaluated. Genomic DNA from these populations was extracted and nine genera of cell endosymbionts were searched by PCR. Three species of the Enterobacteriaceae family, Erwinia amylovora, Serratia grimesii, Yersinia massiliensis and the cell endosymbiont Rickettsia belli were identified in all A. nitens populations. Only Serratia grimesii was found in G. platensis. The presence of E. amylovora, Y. massiliensis and R. belli in the F1 and F2 generations indicates vertical transmission in A. nitens, while S. grimesii is vertically transmitted in G. platensis.  相似文献   

5.
Ascocarpic studies of the ontogeny of Lophodermium nitens disclosed a type of development unlike that of all other species of Hypodermataceae occurring on conifer needles. For this reason the centrum of L. nitens is designated as Type III and is compared with Type I (Gordon, 1966). Because L. nitens produces its ascocarp in several tissues of various species of pine, the ontogeny of ascocarps in different locations is discussed and illustrated. The most significant ontogenetic feature of the ascocarp of L. nitens is a layer of hyaline cells in the primordium; this layer is meristematic and gives rise to all subsequent structures of the centrum.  相似文献   

6.
 This study examines the effect of different soil temperatures on root growth in seedlings of Eucalyptus pauciflora Sieber ex Sprengel subsp. pauciflora and Eucalyptus nitens (Deane & Maiden) Maiden. Seedlings were grown in a glasshouse in pots containing soil. Pots were held in water baths maintained at 3, 7 or 13°C, whilst shoots were exposed to ambient glasshouse temperatures. The experiments were designed to separate direct effects of soil temperature from effects due to differences in seedling size. In the first experiment, seedlings were grown to constant height (25 cm for both species), in the second to constant time (100 days for E. pauciflora and 64 days for E. nitens) and in the third experiment seedlings were transferred between soil temperatures. The rate of growth of both species increased with increasing soil temperature. E. nitens grew faster than E. pauciflora at 7 and 13°C, but E. pauciflora grew faster than E. nitens at 3°C. The rate of browning of roots increased with decreasing soil temperature and at a faster rate in E. nitens than E. pauciflora. Root length was highly correlated to root mass within diameter and colour classes (r2 > 0.7). However, brown roots were heavier than white roots. Consequently, changes in root mass did not reflect changes in root length when the proportion of brown to white root also changed. For example, at a constant height of 25 cm at 3°C, E. nitens had greater root mass but lesser root length than E. pauciflora. E. pauciflora at 3°C grew faster, and had more root length and less brown roots than E. nitens. This supports the argument that E. pauciflora is better adapted than E. nitens to survive and grow at lower soil temperatures. Received: 16 December 1996 / Accepted: 2 April 1997  相似文献   

7.
1. Two cossid moths, Coryphodema tristis Drury and Chilecomadia valdiviana Philippi, have recently become pests on Eucalyptus nitens H. Deane & Maiden in South Africa and Chile, respectively. Both C. tristis and C. valdiviana have large host ranges and high levels of similarity in their host distributions. Their infestations of E. nitens are the first records of these moths on Myrtaceae. 2. The contemporaneous adoption of E. nitens as a novel host, despite widespread availability of native and introduced Myrtaceae, suggests a non‐random pattern of invasion. Phylogenetic relatedness among the two species linked to cryptic invasion of one or both moths at some time in the recent past provides a possible explanation for this pattern. 3. To test this hypothesis, variation in mtDNA sequences for the COI gene of C. tristis and C. valdiviana were analyzed. The COI mtDNA sequence data showed that C. tristis and C. valdiviana are highly divergent genetically, indicating that both are native on their respective continents with independent evolutionary trajectories. 4. The parallel host range expansions to E. nitens on different continents appear to be unrelated events, likely driven by characteristics of the biology and/or ecology of the host.  相似文献   

8.
Significant expansion in the area of eucalypt plantations in Tasmania has led to their establishment at altitudes that are close to the upper limits of the planting distributions of Eucalyptus nitens and E. globulus, the main species planted. This has implications for plantation productivity. We investigated the processes that limit productivity in these environments through a study of freezing-induced depression of photosynthesis of E. nitens saplings in the field and plantlets of E. nitens and E. globulus clones in a controlled environment cabinet. In the field consecutive frosts of around –4.6°C had a cumulative effect, reducing maximum net photosynthesis ( A max) by 17%, and then a further 9%, respectively, compared with saplings insulated from the frosts. Shading saplings pre-dawn had no effect on A max measured after 1030 hours indicating that the reduction in A max at this time was independent of photoinhibition. Recovery of A max to pre-frost levels required at least two consecutive frost-free nights and was dependent on the severity of frost. Photosynthetic light response curves indicated that reduced A max was associated also with decreased quantum yield and stomatal conductance. Similar intracellular carbon dioxide concentration between exposed and insulated saplings indicated that low stomatal conductance did not limit photosynthesis through carbon dioxide limitation. The timing of frost events was critical: E. nitens saplings took less time to recover from reduced A max in the field when they were hardened. Unhardened plantlets of E. nitens and E. globulus clones had greater reduction of A max and took longer to recover from frost events than hardened plantlets. E. globulus was more susceptible to frost-induced reduction of A max than E. nitens. This is consistent with its planting range which is restricted to mild sites compared with that of E. nitens.  相似文献   

9.
A taxonomic revision of the genus Aneorhachis Kleine 1923 (Coleoptera: Brentidae) and a phylogenetic analysis of species belonging to this genus are carried out. The genus Ipsopisthius Kabakov 2001 is synonymised with Aneorhachis, and two new combinations are proposed: Aneorhachis hirta (Kabakov 2001), n. comb. and A. incerta (Kleine 1935), n. comb. Higonius nitens Goossens 2008 is synonymized with A. incerta. One new species is described from New Guinea, A. papuana n. sp. All the species are redescribed and type-specimens are illustrated; an identification key is proposed. A maximum parsimony analysis is provided on the base of 23 characters from adult morphology. This analysis confirms the monophyly of the genus and seems to show that Aneorhachis originated on continental Asia and then spread out eastward to colonize Pacific islands.  相似文献   

10.
none 《Journal of bryology》2013,35(2):147-150
Abstract

Heteroscyphus fissistipus (Hook.f. & Taylor) Schiffn. is reported from Garinish Island in south-west Ireland, new to the Northern Hemisphere. Material collected in 1999 is described and illustrated. Male and female plants are present in pure and mixed patches, and evidence for sporophyte production was observed. H. fissistipus has probably reached Ireland from introduced horticultural sources of antipodean origin.  相似文献   

11.
Zusammenfassung Es wurde der Einfluß der Kationen Na+, K+, Ca2+ und NH 4 + in Verbindung mit dem Anion Acetat auf die Keimungsrate einigerPhycomyces-Stämme (P. blakesleeanus 1+, 2-, 11+ und 18- Sammlung Halbsguth; 188+ und 189-Sammlung Baarn;P. nitens 304+ und 305-Sammlung Baarn) hin untersucht. Es konnte gezeigt werden, daß den Kationen eine wesentliche Rolle im Aktivierungsprozeß zukommt. Förderlich wirkten sich vor allem K+ und Ca2+ Ionen aus. NH 4 + wies keine sichtbar fördernde Wirkung auf, und dem Na- Ion kann eine hemmende Wirkung im besonderen für dieP. blakesleeanus-Stämme 2-, 188+, 189- zugeschrieben werden. Eine vergleichbar empfindliche Reaktion zeigteP. nitens gegenüber Ca2+-Ionen, jedoch nur, wenn höhere Konzentrationen verwendet wurden. Allgemein waren dieP. nitens-Stämme 304+, 305- in ihrer Aktivierbarkeit nicht in dem Maße von den einzelnen Kationen abhängig wie dieP. blakesleeanus-Stämme.Ferner wurde die Wirkung der Wärmeaktivierung auf die Sporenkeimung geprüft. Die günstigste Dauer der Wärmeaktivierung bei 50°C lag für dieP. blakesleeanus-Stämme bei 5 min; dieP. nitens-Stämme vertrugen noch eine Zeit von 40 min (50°C) ohne erkennbare Schädigung.Die Aktivierbarkeit der Sporangiosporen in Abhängigkeit vom Aktivierungsagens (Acetat bzw. Wärme) zeigte deutliche Unterschiede zwischen denP. blakesleeanus- undP. nitens-Stämmen.
Activating of germination dependent on lons of sporangiospores ofPhycomyces blakesleeanus andP. nitens, demonstrated on various strains
The influence of cations Na+, K+, Ca2+ and NH 4 + in connection with anion acetate on the rate of germination was studied for severalPhycomyces strains (P. blakesleeanus 1+, 2-, 11+, 18- collection Halbsguth; 188+, 189- collection Baarn;P. nitens 304+ and 305- collection Baarn). Cations played an important role during the activating process; NH 4 + did not further the effect. The Na+ ion inhibited. The inhibition was marked onP. blakesleeanus strains 2-, 188+ and 189-. A comparable sensitive reaction ofP. nitens was apparent towards Ca2+ ions, when higher concentrations were used. Generally activations ofP. nitens strains 304+ or 305- were not influenced by the different cations as much as were theP. blakesleeanus strains.Furthermore the effect of heat activation on spore germination was tested. The most favourable time period for heat activation at 50°C was 5 min for theP. blakesleeanus strains, while theP. nitens strains tolerated a period of 40 min at 50°C without any detectable damage (90% germinated spores).The ability ofPhycomyces sporangiospores to be activated showed differences between theP. blakesleeanus andP. nitens strains depending on the activating agent (heat or acetate).
  相似文献   

12.
Genetic-parameter estimates and parental breeding-value predictions were compared from open-pollinated and control-pollinated progeny populations of Eucalyptus globulus and two populations of E. nitens. For E. globulus there were two types of open-pollinated populations (native stand open-pollinated and seed orchard open-pollinated) and two types of control-pollinated populations (intra-provenance and interprovenance full-sib families). For E. nitens there were two populations, a seed orchard open-pollinated population and intra-provenance full-sib families. Progeny tests were established across multiple sites and 2-year height and diameter were measured and volume calculated. Genetic parameters from native stand open-pollinated E. globulus were unlike the parameters from the other three E. globulus populations; heritability estimates were severely inflated, presumably due to high levels, and possibly differential levels, of inbreeding depression relative to the other populations. Estimates of dominance variance in the E. globulus full-sib populations were high, but were zero in the E. nitens population. Correlations among parental breeding values, predicted using data from the different populations, were generally low and non-significant, with two exceptions: predictions from the two E. globulus full-sib populations were significantly correlated (r=0.54, P = 0.001), as were predictions from the E. nitens seed orchard OP and full-sib population (r = 0.61, P = 0.08). There was some indication that superior parents of E. globulus native stand open-pollinated families also tended to have above-average breeding values based on the performance of intra-provenance full-sib offspring. The consequences of these results for exploitation of base-population collections from native stands are discussed.  相似文献   

13.
《Journal of bryology》2013,35(4):305-309
Abstract

The discovery of Paludella squarrosa (Hedw.) Brid., new to Ireland, is reported. This Boreo-arctic Montane species has a relic distribution in western and central Europe and was formerly more widespread. The reasons for its decline and its documented extinction from Britain and the Netherlands in recent times are discussed. The vegetation and ecology of the Irish locality are described. The associated species include Leiocolea rutheana, another Boreal relic species and a second record for Ireland.  相似文献   

14.
《Journal of bryology》2013,35(2):89-95
Abstract

Ephemerum hibernicum sp. nov. is described from inundation zones of two lakes and a river in north-central Ireland and a river in western Ireland. It is most similar to E. crassinervium and E. sessile, but differs from both of these in several characters of the leaves. In particular, papillae on the upper lamina are much lower than in most E. crassinervium, while the leaves are longer and wider than in E. sessile, with a wider lamina towards the leaf apex, less well-defined costa and sometimes with large spinose marginal teeth. Ephemerum hibernicum is a rare species and its specialized habitat merits conservation.  相似文献   

15.
《Journal of bryology》2013,35(2):161-162
Abstract

The occurrence of subspecies pallidicaulis of Fissidens taxifolius in West Scotland and South-West Ireland is reported.  相似文献   

16.
《Journal of bryology》2013,35(3):469-478
Abstract

Leiocolea fitzgeraldiae sp. nov. from Wales, Scotland and Ireland is described and illustrated. Comparisons between it and the related species L. bantriensis and L. alpestris are outlined. Its cytology and habitat preferences are discussed and a distribution map is given.  相似文献   

17.
Plumatella nitens is a newly recognized species of phylactolaemate bryozoan in North America. It has previously been combined with either P. repens or P. fungosa, from which it differs primarily by the floatoblast. In P. nitens the ventral floatoblast annulus is uniformly narrow with no significant widening at the poles. The dorsal floatoblast fenestra is conspicuously larger than in either P. repens or P. fungosa. Reticulated ridges on the dorsal fenestra are weak along the margins, becoming unusually prominent in the center. The sessoblast is densely covered with uneven papillae. Spotty sampling so far shows a distribution only in the northern half of North America, including Massachusetts, Michigan, Minnesota, Wisconsin, Ontario, and the northern regions of Illinois, Indiana, and Ohio.  相似文献   

18.
《Journal of bryology》2013,35(4):264-267
Abstract

Grimmia anomala is reported from seven sites in Scotland and Ireland. Confusion in the past with Grimmia hartmanii has meant that this species has been overlooked. Its occurrence in Scandinavia and the Faroes means that its sites in Scotland are not unexpected but the Irish localities for this boreal-montane species are noteworthy.  相似文献   

19.
1 Gonipterus scutellatus is a weevil that has become a pest in most Eucalyptus plantations in Africa, America and Europe. The egg parasitoid Anaphes nitens has been introduced into many countries as a biological control agent. Even if control has been successful in most countries no detailed study of the interactions between both species has been published. 2 Gonipterus scutellatus was detected in 1991 in north-west Spain and A. nitens was introduced in early 1994. Here we report on the results of a 2-year study of parasitism in a field plot and a survey of 16 localities in North-west Spain. In 1996, parasitism was so intense (80–100% of eggs) that G. scutellatus became locally extinct, and as a consequence A. nitens disappeared. In 1997, G. scutellatus recolonized the area and was followed by its parasitoid, but parasitism was low in spring, probably because the parasitoid population needed 3 weeks to achieve a similar size as in 1996. Consequently, damage to the trees was extreme in 1997. We interpret these results as population fluctuations due to parasitoid–host interactions and suggest that parasitoids should not to be so effective as to locally extinguish their host to be useful for biological control. 3 The analysis of parasitism level in 16 localities indicates that A. nitens is highly efficient in finding G. scutellatus egg-masses. At a small spatial scale (single trees) positive density dependence was detected where parasitism was low and inverse density dependence where parasitism was high.  相似文献   

20.
An integrated genetic linkage map for E. nitens was constructed in an outbred three-generation pedigree. Analysis of 210 RFLP, 125 RAPD and 4 isozyme loci resulted in 330 markers linked in 12 linkage groups covering 1462 cM (n=11 in eucalypts). The 12th linkage group is comprised of only 5 markers and will probably coalesce with another linkage group when further linked loci are located. Co-dominant RFLP loci segregating in both parents were used to integrate linkages identified in the male and female parents. Differences in recombination frequencies in the two parents were observed for a number of pairs of loci, and duplication of sequences was identified both within and between linkage groups. The markers were distributed randomly across the genome except for the RFLPs in linkage group 10 and for some loci showing segregation distortion, which were clustered into three regions of the map. The use of a large number of co-dominant RFLP loci in this map enables it to be used in other pedigrees of E. nitens and forms a basis for the detection and location of QTL in E. nitens and other eucalypt species.  相似文献   

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