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31.
Hilde Nybom 《Plant Systematics and Evolution》1986,152(3-4):211-218
A review of current knowledge of chromosome numbers and modes of reproduction in the genusRubus L. is presented. Chromosome numbers from some species of subg.Malachobatus
Focke together with results of crossing experiments are reported for the first time. 相似文献
32.
The family Heteroderidae, its two subfamilies Heteroderinae and Meloidogyninae and the nominal genera of Heteroderinae (Heterodera Schmidt, 1871; Meloidodera Chitwood, Hannon &Esser, 1956; and Cryphodera Colbran, 1966) are rediagnosed. Meloidoderita Pogosyan, 1966 is considered a genus inquirenda. Two new genera from southern California are described in the subfamily Heteroderinae. A key to the genera, illustrations and a phylogeny of the Heteroderinae are proposed. 相似文献
33.
Three new coccoid zoospore-producing green algae includingAxilococcus clingmanii gen. & spec. nov.,Lautosphaeria monsfumosa gen. & spec. nov., andDictylochloris pulchra spec. nova (Chlorococcales, Chlorophyceae) are described.Dedicated to Prof. DrLothar Geitler on the occasion of his 90th birthday. 相似文献
34.
B. D. Mowrey D. J. Werner 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1990,80(1):129-133
Summary An isozyme survey of 34 species of Prunus representing subgenera Prunus, Amygdalus, Cerasus, and Lithocerasus detected 110 presumptive alleles at 11 isozyme loci. Principal component analysis was conducted on the covariance matrix derived from allelic frequencies calculated for each species. Cluster analysis was performed on the first 30 principal components. Results generally support traditional classification of Prunus at the subgeneric level, except for members of subgenus Lithocerasus and two members of subgenus Amygdalus. Prunus glandulosa Thunb., P. japonica Thunb., and P. tomentosa Thunb. of subgenus Lithocerasus and P. triloba Lindl. of subgenus Amygdalus appear to represent primitive species. P. besseyi Bailey and P. pumila L. of subgenus Lithocerasus and P. andersonii of subgenus Amygdalus should be assigned to subgenus Prunus. Placement of its members indicates that subgenus Lithocerasus is an artificial grouping of species that are very different genetically although similar phenotypically.Paper No. 12529 of the Journal Series of the North Carolina Agricultural Research Service, Raleigh, NC 27695-7643, USA 相似文献
35.
Six species of the genus Eumonhystera, one of which is new to science, are described from bottom samples of Lake Tana and two associated rivers, River Abbay and R. Gelda, Ethiopia. E. geraerti n.sp. can be identified by being the only species in the genus that combines very posteriorly positioned vulva [V% = 68.2 ± 0.7 (67.3–69.3)] with very anteriorly positioned amphids (Amph-ABE/LRW = 0.8). The other five species encountered, E. dispar (Bastian, 1865) Andrássy, 1981, E. filiformis (Bastian, 1865) Andrássy, 1981, E. pseudobulbosa (von Daday, 1896) Andrássy, 1981, E. mwerazii (Meyl, 1957) Andrássy, 1981, and E. vulgaris (de Man, 1880), Andrássy, 1981, are described in detail. The identities of some of the already described populations of E. dispar, E. filiformis and E. vulgaris are questioned and clearer and better ways of defining each of these three species are suggested. A peritrophic-like membrane on the outer side of the brush-border of the intestine of E. mwerazii, a species reported here for the first time out of its type locality, is reported. Also, scanning electronmicrographs of sectioned and entire specimens of E. mwerazii are presented. All species are reported from Ethiopia for the first time. 相似文献
36.
Species boundaries,phylogenetic relationships,and ecological differentiation inAnthriscus (Apiaceae)
Krzysztof Spalik 《Plant Systematics and Evolution》1996,199(1-2):17-32
Species boundaries and phylogenetic relationships of 17 taxa ofAnthriscus (Apiaceae), with special emphasis on the critical sect.Cacosciadium, were explored using morphological data with principal component analysis, phenetics, and phylogenetics. The analyses did not provide satisfactory resolution of taxa from sect.Cacosciadium and only four species were retained. The total number of species was reduced to nine. Sect.Cacosciadium is distinguished by only two synapomorphies while sects.Anthriscus andCaroides are better supported. Present geographic and ecological variation suggests that the radiation ofAnthriscus occurred through divergence of peripheral isolated populations adapting to different habitats: high montane meadows and screes, shady climax forests, and seasonally dry habitats at lower altitudes. The adaptive significance of particular morphological traits is discussed. 相似文献
37.
A new taxonomic treatment is proposed for thePottia starckeana species complex. The peristome development is not considered to be a useful feature to separate the taxa. On the basis of spore morphology only two species are accepted:P. starckeana, with spores wavy in outline, andP. davalliana, with variously-shaped and developed processes on the spores.Pottia starckeana var.brachyoda is reduced to synonymy withP. starckeana; P. conica andP. commutata are treated as synonyms ofP. davalliana. The speciesP. mutica, P. affinis, P. salina, P. microphylla, P. texana, andP. arizonica (included var.mucronulata) are considered taxa of doubtful affinity, as they have spore features intermediate between the two spore types established for the group. The identity ofP. appertii andP. recurvifolia has not been elucidated because the type material has been destroyed. 相似文献
38.
中国野豌豆属的分类研究 总被引:8,自引:0,他引:8
本文报道了国产野豌豆属43种,4变种及6变型,其中包括4个新种(多叶野豌豆,三尖野豌豆,武山野豌豆,长齿野豌豆);一个新变种(三叶歪头菜)及一个新等级(千山野豌豆)。 相似文献
39.
40.
Yuzo Yamada Minako Matsuda Kozaburo Mikata 《Journal of industrial microbiology & biotechnology》1995,14(6):456-460
Summary Two strains ofEeniella nana were examined for their partial base sequences of 18S and 26S rRNAs. In the partial base sequences of 18S rRNA (prositions 1451 through 1618, 168 bases) the strains ofE. nana have five, five, four and eleven base differences with those ofDekkera bruxellensis (type species).D. anomala (andBrettanomyces anomalus),D. naardenensis andD. custersiana, respectively. In the 26S rRNA partial base sequencings (positions 1611 through 1835, 225 bases and positions 493 through 622, 130 bases) the base differences were 46, 43, 34 and 40 and the percent similarities were 53–54, 51–54, 56–57 and 51–53, respectively. The sequence data obtained are discussed phylogenetically and taxonomically, especially on retention of the generic nameEeniella.This paper is dedicated to Professor Herman Jan Phaff in honor of his 50 years of active research which still continues.Significance of the coenzyme Q system in the classification of yeasts and yeast-like organisms. Part LVIII. For part LVII, see ref. [20]. 相似文献