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1.
Polytretophora macrospora is introduced based on specimens from two species ofPandanus in Seychelles. The new species is compared with currently accepted species. A key and a comparative synopsis toPolytetophora species are provided. Numerous specimens ofP. calcarata, collected on members of the Pandanaceae from Australia, Fiji, Hong Kong, Malaysia, New Caledonia, Palau, Philippines, Seychelles and Solomon Islands are also reported, along withP. dendroidea onPandanus sp. from Malaysia.  相似文献   

2.
A taxonomic revision ofVerbesina sect.Ochractinia is presented. 40 species plus 7 additional infraspecific taxa are recognized. A table of the distribution of the species, key to the species and synonymy are included. Relationships to other sections ofVerbesina and species relationships within sect.Ochractinia are discussed.  相似文献   

3.
Cylindrocladium angustatum is described as a new species fromTillandsia introduced with plant material into the U.S.A. from Central America. Koch's postulates are established to prove its pathogenicity to this host. The species is compared with and distinguished fromC. heptaseptatum andC. rumohrae based on morphology, cultural characteristics and phylogenetic analysis of sequence data of the beta-tubulin gene.  相似文献   

4.
Species ofAnthostomella reported from Brunei have been re-examined and the data is summarized in this paper. Five species are accepted, four are synonyms of previously described species and one is a new species. The new speciesAnthostomella oblongata is described and illustrated and a list ofAnthostomella species known from Brunei and a key to these species are provided.  相似文献   

5.
Genetic relationships were studied by means of ten isoenzymatic systems, at the genus and species level, using two distances and four methods of aggregation in a germplasm collection of 198 cultivars and accessions of 54 species belonging to Citrus and 13 related genera. The most consistent results were obtained by the chord distance and the neighbor-joining clustering method. Citrus species were distributed in two main groups: the orange-mandarin group and the lime lemon-citron-pummelo group. The species C. halimii and C. tachibana are not included in these groups. Mandarin species fall into three main subgroups: one includes C. sinensis; the second, C. aurantium, the third, small-fruit species. The citron, the pummelo and the ancient lemon subgroups form a cluster to which the species belonging to subgenus Papeda and the cultivated limes, lemons and bergamots are related. Microcitrus spp, to which Severinia buxifolia and Atalantia ceylanica seem to be related, cluster with the lime lemon-citron-pummelo group while Fortunella is close to the orange-mandarin group. Poncirus trifoliata, the most important species for citrus rootstock improvement is located far from Citrus but connected to it through Fortunella spp. A broad distribution of species has been found that should be taken into account to sample new genotypes in the search of desired characters in order to fully and efficiently use genetic resources for citrus improvement.  相似文献   

6.
Here we describe a new species ofCorydalis sectCorydalis (Fumariaceae), namely C.hirtipes B.U. Oh et J.G. Kim. This species, from the central part of Korea, is clearly distinguished from other species of sectCorydalis by its simple, unicellular hairs that are densely distributed on the stems, peduncles, and petioles. It is also distinctive from its close relative C.albipetala in having ternate leaves, lobate or parted leaflets, dentate or cleft bracts, and broad, fusiform fruits.  相似文献   

7.
A new species of Neodiaptomus, N. intermedius n. sp. is described and illustrated. It is compared with related species of the strigilipes — physalipus species group.  相似文献   

8.
ALeptographium species was isolated from deadPinus densiflora at six sites in Japan. The fungus is morphologically most similar toL. lundbergii but could be distinguished from that species by its short stipes, primary branches of conidiophores, and conidia with a rounded to sub-truncate base. In addition, the colony morphology, growth rate and tolerance to the antibiotic cycloheximide of theLeptographium species andL. lundbergii differed markedly. Here we describe the fungus as a new species,Leptographium pini-densiflorae. Contribution No. 144, Laboratory of Plant Pathology and Mycology, Institute of Agriculture and Forestry, University of Tsukuba.  相似文献   

9.
Taxonomy of the genus Cristulariella is revised, retaining Cristulariella (Crist.) depraedans as the type. Two new species, Crist. cercidiphylli and Crist. corni, are additionally described under the genus. The new anamorphic genus Hinomyces is erected to accommodate Botrytis (Cristulariella) moricola and Cristulariella pruni. A new genus and species, Nervostroma depraedans, is erected in the Sclerotiniaceae to accommodate the teleomorph of Crist. depraedans, with an additional species, Nervostroma cercidiphylli.  相似文献   

10.
A cytological analysis of 37 experimental interspecific hybrids withinEpilobium sect.Epilobium, involving 23 taxa, has indicated that the CC chromosome arrangement differs from BB by a single reciprocal translocation and was probably, like AA and DD, derived from it. Preliminary results suggest that the CC arrangement may characterize the AsianE. cephalostigma andE. platystigmatosum, which do not closely resemble the species in which it had earlier been detected. The BB arrangement is shown to occur in all North American species of theE. palustre group, includingE. oregonense. Direct evidence on chromosome arrangement is now available for some 85 of the approximately 185 species of the section, and may be inferred for at least 25 more.  相似文献   

11.
12.
A new Conchostracan species, Eocyzicus spinifer from Iraq is described. A table is given to distinguish the known species of the genus Eocyzicus.  相似文献   

13.
14.
Entyloma species causing white smut disease of Cosmos species have been studied. Two species can be recognized, Entyloma holwayi on C. caudatus and C. sulphureus from North America, and E. cosmi sp. nov. on C. bipinnatus from Japan and Europe.  相似文献   

15.
A new teleomorphic genus Ascobotryozyma, with a single species, A. americana, is proposed. Its anamorph is a Botryozyma that differs from the type species, B. nematodophila, on distributional, physiological, and molecular criteria; it is described as Botryozyma americana, anam. sp. nov. Ascobotryozyma is characterized by globose asci bearing four lunate ascospores. Fusion of thallus cells precedes ascus formation. Ascobotryozyma americana was isolated from the surface of nematodes (Panagrellus dubius) associated with galleries of the poplar borer (Saperda calcarata) in trembling aspen (Populus tremuloides) in eastern Washington, USA. The teleomorph has not been produced in pure culture.  相似文献   

16.
Carracedo MC  Suarez C  Casares P 《Genetica》2000,108(2):155-162
The sexual isolation among the related species Drosophila melanogaster, D. simulans and D. mauritiana is asymmetrical. While D. mauritiana males mate well with both D. melanogaster and D. simulans females, females of D. mauritiana discriminate strongly against males of these two species. Similarly, D. simulans males mate with D. melanogaster females but the reciprocal cross is difficult. Interspecific crosses between several populations of the three species were performed to determine if (i) males and females of the same species share a common sexual isolation genetic system, and (ii) males (or females) use the same genetic system to discriminate against females (or males) of the other two species. Results indicate that although differences in male and female isolation depend on the populations tested, the isolation behaviour between a pair of species is highly correlated despite the variations. However, the rank order of the isolation level along the populations was not correlated in both sexes, which suggests that different genes act in male and female sexual isolation. Neither for males nor for females, the isolation behaviour of one species was paralleled in the other two species, which indicates that the genetic systems involved in this trait are species-pair specific. The implications of these results are discussed. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

17.
Karyotype and external morphological analyses were conducted onMedicago ciliaris, M. intertexta, M. muricoleptis andM. granadensis which comprise theIntertextae section of the genusMedicago. All species were found to have 2n = 16 chromosomes (= 2 ×), including one pair of satellite chromosomes in each respective complement. Karyotypic evolution in theIntertextae involves changes in absolute chromosome size and in centromeric and relative size symmetry. Numerical taxonomic analyses were conducted independently on 17 karyotypic features and on 16 features of external morphology. The results of the two sets of analyses proved comparable, withM. ciliaris andM. intertexta forming a fairly close pair, and the remaining two species appearing to have more distant relationships to each other and to the first pair. These observations are consistent with the infertility relationships and chorologies of the species. It is suggested thatM. muricoleptis andM. granadensis are derived from theM. ciliaris/intertexta species complex withM. granadensis arising fromM. muricoleptis, or these two species independently evolving from a common species complex. Chromosomal and numerical analyses suggest thatM. ciliaris is the most primitive andM. granadensis the most derived species of theIntertextae.  相似文献   

18.
Type examination ofTrametes gilvoides revealed that it is distinct from the fungus hitherto known asPhellinus gilvoides in Japan.Phellinus setifer sp. nov. is described for the Japanese materials. This species is characterized by effusedreflexed basidiocarps with strigose pileus surface, often dentate dissepiments, subulate setae, and cylindrical basidiospores.Phellinus acontextus, known only from the type material collected in Nepal, is newly reported from Japan. This species is characterized by sessile and often pendent basidiocarps with multisulcate pileus surface, very thin context, lack of setae, and dark-colored basidiospores. Cultural characters of the two species are also described.Phellinus acifer comb. nov. is proposed.Phellinus contiguus andP. ferreus are newly reported from Japan.  相似文献   

19.
The underlying mechanisms of drought resistance in seedlings ofLarix kaempferi as compared with those inAbies veitchii were investigated. First, seedlings of the two species were desiccated in air of differing water potential, and their survival rates were compared to detect any difference in desiccation tolerance between them. Contrary to differences in their drought resistance,A. veitchii showed higher survival. Next, the shoot heights and root depths of the two species were compared to detect any difference in desiccation avoidance. Although the shoot height differed little between the two species, the roots ofL. kaempferi seedlings were much deeper than those ofA. veitchii seedlings, and the death rate under progressing drought was well correlated with the root extensibility of each species. It was thus concluded thatL. kaempferi seedlings are able to avoid desiccation by extending their roots in deep soil faster thanA. veitchii seedlings, thereby resisting to drought. This paper is dedicated to Prof. Toshiro Saeki to mark his fruitful career in plant ecology.  相似文献   

20.
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