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1.
New sequences have been produced of the ITS rDNA region of twenty-nine species ofParmeliaceae, and analysed by neighbour-joining maximum likelihood distance analysis, and maximum parsimony analysis. Twelve monophyletic groups have been identified, most of which correspond to proposed generic segregated fromParmelias. lat.ParmeliaandParmelina,Melanelia, andPuncteliaappear as independent monophyletic groups; the type species of the two latter genera were, however, not included in the analysis. The parsimony analysis does not supportXanthoparmeliaas a monophyletic group separate fromNeofuscelia, andRimelia reticulatais nested withinParmotrema. Parmelinopsis horrescensis more closely related toHypotrachyna revolutathan toParmelina. Genetic distance values suggest thatFlavoparmelia caperatais closer toParmotremathan to other taxa included, and thatPlatismatia glaucaandHypogymnia tubulosaare closer toParmelias. lat. than to thePhysciaceae. However, there is no conclusive support for any of the latter groupings in the parsimony analysis. We conclude that the ITS region contains valuable information for studying generic delimitations within the familyParmeliaceae, but our study suggests that this region will not conclusively resolve within-family relationships in this group.  相似文献   

2.
Treatment of Parmelia caperata, P. perlata, P. subrudecta, P. sulcata and P. tiliacea with CuSO4 resulted in a time- and copper-concentration-dependent decrease in the total and intracellular potassium concentrations of the thallus, indicating that copper damaged the cytoplasmic membrane. Treatment with copper also resulted in a time-dependent increase in the total copper concentration of the thallus. After 4 h of exposure to copper, the process of potassium efflux was essentially completed but the absorption of copper was still increasing; moreover, the amount of copper bound to the thallus exceeded twice the amount of potassium released from the thallus, suggesting that cupric ions reached intracellular sites in the thallus, and K+/Cu2+ exchange was not electroneutral. After 5 h of exposure to copper, the extent of decrease in the total and intracellular potassium concentrations of the thallus was positively correlated with copper absorption levels, but only at 0.05<P<0.10, suggesting that membrane damage was proportional to the amount of bound copper, but other factors could have been operative, namely binding of copper to the cell wall. Acetone extracts of untreated thalli contained low concentrations of amino acids, polyols, and sugars, but considerable amounts of lichen substances: atranorin, caperatic, constictic, lecanoric, menegazziaic, protocetraric, salazinic, stictic, and usnic acids. Titration of the extracts with copper and assay of the free Cu2+ concentration revealed the presence of copper-binding ligands, and several successive absorption cycles, most probably corresponding to the binding of Cu2+ to each of the lichen substances detected in the extracts. However, no significant correlation (P>0.10) was found between the Cu2+-complexing capacity of acetone extracts and copper-induced membrane damage. It was concluded that in the studied Parmelia species, and in the experimental conditions used in this work, copper toxicity was not a simple function of the Cu2+-binding properties of the lichen substances present in the thallus. Several hypotheses were formulated to interpret the results.  相似文献   

3.
Bilie L. Turner 《Brittonia》1986,38(2):123-127
Three new species ofPhacelia from Nuevo León, Mexico are described and illustrated. Two of these,P. hintoniorum andP. potosina, belong to theCrenulata group; the former, with included anthers, relates toP. coerulea; the latter, with exserted anthers, relates toP. alba orP. coulteri. The remaining novelty,P. zaragozana, belongs to the subgenusCosmanthus where its closest relationship is withP. laxa.  相似文献   

4.
A new species,P. grandiloba, and a new variety,P. pamirica var.khunjrabensis, from Pakistan are described. New status has been given toP. grisea var.vilijuga. P. aphanes is recorded for the first time from Pakistan.  相似文献   

5.
Pinguicula rotundiflora (Lentibulariaceae), a new species from southern Mexico related toP. parvifolia Robinson is described and illustrated.  相似文献   

6.
Part of the Lichenological Herbarium of the University of Trieste (TSB) was infested by Lasioderma serricorne, a polyphagus coleopteran. 1440 samples of 50 lichen species with different chemistry (Parmelia s.lat., Physcia s.lat.) were analyzed in order to assess whether the lichen diet of the insect was species- and especially lichen-chemistry-selective. Multivariate analysis indicates a significant negative correlation between the presence of some lichen substances and grazing phenomena. Atranorin, calcium oxalate, fumarprotocetraric acid, gyrophoric acid, lecanoric acid, skyrin, usnic acid and zeorin play an antiherbivorous role.  相似文献   

7.
Evidence from morphology, flavonoid chemistry, and field observations suggests thatPopulus acuminata is of hybrid origin. The putative parents areP. angustifolia, the narrow leaf cottonwood, and deltoid leaved plants that are assigned toP. sargentii (P. deltoides var.occidentalis), P. fremontii, orP. wislizenii (P. fremontii var.wislizenii). Populus angustifolia exhibits a series of flavonol glycosides (kaempferol, quercetin, and myricetin) in its leaves. By contrast, the major leaf flavonoids of the broad leaved plants are flavone glycosides (apigenin and luteolin).Populus acuminata is intermediate between the suspected parents in morphological features. Additionally, the leaves of mostP. acuminata plants contain the exact summation of the flavonoid compounds characteristic of the putative parents. A diploid chromosome number of 2n = 38 was obtained for six plants, which confirms the one previous report for the species. Meiosis was regular in all cases. Correlated data indicate that the majority of plants ofP. acuminata represent F1 hybrids and that complex hybridization is not common. Evidence from morphological and chemical studies is presented to show that in certain instances backcrossing to both parents has occurred. Results gathered in this study show thatP. ×andrewsii is undoubtedly “typical”P. acuminata, but the type specimen is from a sucker shoot, and thus has been interpreted as a backcross toP. sargentii. Populus acuminata var.rehderi is not considered worthy of taxonomic recognition.  相似文献   

8.
Potamogeton distinctus has an E. Asian distribution and is closely related toP. nodosus. P. tepperi seems to be a synonym ofP. tricarinatus, even though the name has frequently been applied to other species likeP. distinctus. P. indicus is a synonym ofP. nodosus notwithstanding the fact that not all Indian broad-leaved pondweeds belong to that taxon.  相似文献   

9.
The new species is the fourth member of the genus. Morphologically, it is most closely allied toP. liebmannii, but there are ample qualitative and quantitative differences between them. The chromosome numbers ofP. liebmannii andP. nelsonii are 2n = 56 whileP. zinnioides is 2n = 84.Philactis fayi is 2n = 28 and is considered to represent the diploid complement that was probably involved in the production of the other species through hybridization and chromosome doubling.  相似文献   

10.
Brian M. Boom 《Brittonia》1989,41(2):129-130
Pagamea aracaënsis Boom, endemic to Serra Aracá, Brazil is described and illustrated, and its relationship toP. anisophylla Standley & Steyerm, is discussed.  相似文献   

11.
The efficacy ofPaecilomyces fumosoroseus (Wize) Brown & Smith,P. farinosus (Holm ex S. F. Gray) Brown & Smith,Beauveria bassiana (Balsamo) Vuillemin,Metarhizium anisopliae (Metschnikoff) Sorokin and an entomoparasitic nematode,Steinernema feltiae (Filipjev), against larvae and pupae of the apple fruit mothArgyresthia conjugella (Zell.) (Lepidoptera: Yponomeutidae) was studied in field and laboratory experiments. All species of fungi and the nematode were highly pathogenic to larvae in Petri dishes. In soil, the pathogenicity ofB. bassiana andP. farinosus for larvae decreased. Pupae inside cocoons were highly susceptible toP. fumosoroseus, but not toP. farinosus orB. bassiana. In the field experiment, treatment of soil with conidia ofP. fumosoroseus at a rate of 1×107 conidia per cm2 reduced the emergence of overwinteredA. conjugella adults by 70.1% compared to untreated control soil.  相似文献   

12.
13.
Liparis molendinacea is related toL. deistelii and known so far only from the type locality in Kawambwa district in the Northern Province of Zambia.L. nyikana likewise is related toL. deistelii, it is distributed in E. and SW. Tanzania and in N. Malawi.L. chimanimaniensis is related toL. nervosa and known so far only from the Chimanimani Mountains in the Eastern Province of Zimbabwe.  相似文献   

14.
Morphological variation ofPotentilla norvegica L.,P. heidenreichii Zimmeter andP. supina L. usually treated within the sectionRivales Wolf,P. recta L. (sect.Rectae Wolf),P. canescens Bess.,P. argentea L. s.l.,P. collina Wibel (sect.Argenteae Wolf) andP. goldbachii Rupr. (sect.Chrysanthae Wolf) was studied using multivariate statistical methods. According to k-means clustering,P. canescens stands closer toP. heidenreichii of the sect.Rivales than toP. argentea. P. collina, the other representative of sect.Argenteae, is not connected withP. canescens at all. Therefore,P. canescens should belong to sect.Rivales and not to sect.Argenteae. InPotentilla argentea s.l.,P. impolita Wahlenb.,P. argentea L. var.argentea, var.decumbens (Jord.)Lehm., var.demissa (Jord.) Lehm., var.grandiceps (Zimmeter) Rouy etE.G. Camus and var.tenerrima (Velen.) Wolf were identified.P. impolita specimens did not cluster out into a separate cluster as didP. collina, P. canescens andP. heidenreichii, but formed mixed clusters with different varieties ofP. argentea s.str. Therefore,P. impolita is not worthy of the rank of species and evidently not even that of subspecies, and should be treated as a variety—P. argentea var.incanescens (Opiz) Focke.  相似文献   

15.
Taxonomy and distribution ofParietaria serbica.Pan?,P. lusitanica L.,P. micrantha Lebed. andP. mauritanica Dur. is briefly discussed.P. serbica is an endemic species of SE. Europe and is related toP. judaica Strand in L.P. lusitanica is divided into two subspecies.P. micrantha is treated as a variety ofP. lustitanica subsp.chersonensis (Lang) Chratek.P. mauritanica is reported as a new species for Sicily.  相似文献   

16.
Dalechampia fernandesii, from Ceará, belongs to sectionTiliifoliae and is related toD. affinis andD. tiliifolia.Dalechampia armbrusteri, of subsectionDalechampia, from Bahia, is close toD. brownsbergensis of Suriname but has well developed resiniferous bractlets.Dalechampia viridissima, from Bahia and Espírito Santo, is an isolated species with the 3-lobed leaves of species in sectionDalechampia subsectionDalechampia but the reduced indumentum and greenish bracts of species in sectionTriphyllae.  相似文献   

17.
18.
Two new species are added toCryptochloa,C. unispiculata from Peru andC. capillata from Brazil, the latter transferred from the genusOlyra. The genusPiresia is also augmented by two new species,P. macrophylla from Peru andP. leptophylla from Bahia, Brazil. These species represent, respectively, the westernmost and easternmost limits of distribution of the genus.  相似文献   

19.
A numerical taxonomic study was conducted on the common narrow-leaved members of the genusChenopodium that occur in the western United States. As many as six and as few as two species have been recognized. Thirty-five individual popu lations were used as OTU’s, and 35 characters were considered. The data were subjected to cluster (both the weighted-pair group method and the within-group dispersion method) and principal component analysis. The results of both analyses are in general agreement and suggest phenetic relationships that differ from current interpretations in the literature. It is concluded thatC. desiccatum var.leptophylloides is much more closely related phenetically toC. atrovirens (and may not be distinct from it) than it is toC. desiccatum var.desiccatum. Chenopodium hians andC. leptophyllum appear to be phenetically distinct despite the fact that they have sometimes been viewed as conspecific.Cheno podium subglabrum is not very similar toC. leptophyllum, and should probably be treated as a separate species rather than as a variety of the latter. Popu lations referable toC. incognitum form a rather loose cluster that appears some what intermediate between populations ofC. desiccatum var.leptophylloides,C. atrovirens, C. hians, andC. leptophyllum.  相似文献   

20.
Aphidius staryi Chen & Luhman n. sp. is described. The species was collected and introduced into California from Israel and Turkey byD. González. The new species is morphologically most similar toAphidius smithi, and keys toEady's urticae group.  相似文献   

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