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21.
J. Heinrichs T. Pröschold C. Renker H. Groth D. S. Rycroft 《Plant Systematics and Evolution》2002,230(3-4):221-230
Plagiochila dubia Lindenb. & Gottsche is reduced to a synonym of the Neotropical P. patula (Sw.) Lindenb. Specimens from the Canary Islands and Madeira proved to belong to the eastern North American P. virginica A.Evans, new to Europe. Phylogenetic analyses of the internal transcribed spacer regions (ITS1-5.8S-ITS2) of nuclear ribosomal
DNA of ten Plagiochila species produced four independent lineages that are well supported by all bootstrap analyses (maximum likelihood, maximum
parsimony, and distance). These lineages correspond with the Plagiochila sections Arrectae, Contiguae, Cucullatae and Glaucescentes. Spruce's “Ramiflorae” and “Cauliflorae” may no longer be regarded as monophyletic units of Plagiochila.
Received August 19, 2001 Accepted October 11, 2001 相似文献
22.
To examine geographic differentiation in Asarum heterotropoides var. heterotropoides in Hokkaido Is. in the northern Japan, in which two putative cryptic species have been suspected to exist, extensive and
detailed morphological research on 794 individuals from 44 populations throughout Hokkaido Is. was performed. Among the characters
examined, the angle between and tip shape of the calyx lobes and the supratecta of the pollen grains were significantly correlated
and were found in similar geographic clines. Among them, the pollen showed two discrete states in almost distinct distribution.
Multidimensional scaling analysis showed that individuals within each of the two pollen types had different trends in flower
characters. Consequently, we assumed a cline from south to north on Hokkaido Is. For the causes of the cline, the two hypotheses
were proposed, primary geographic differentiation or extensive introgressive hybridization between two distinct geographical
species existing in the past. 相似文献
23.
Janina Przybylska Zdzislawa Zimniak-Przybylska 《Plant Systematics and Evolution》1997,208(3-4):239-248
This work is a continuation of electrophoretic investigations aimed at revealing a wild relative ofVicia faba. Electrophoretic analysis (PAGE) of seed albumins covered 52 accessions representing eightVicia species of sect.Hypechusa and two species of sect.Peregrinae. Most of the examined species showed an intraspecific variation due to differences between accessions and/or individual variation within accessions. In spite of the intraspecific variation, marked interspecific differences were recorded. However, none of the investigated species displayed electrophoretic seed albumin patterns similar to those reported earlier forV. faba. Contribution of the obtained results to characterization of the examined taxa is discussed. 相似文献
24.
Crossing experiments were carried out in order to investigate the importance of apogamy in relation to autogamy, geitonogamy and xenogamy in the reproductive biology of pentaploid members of the genus Rosa, section Caninae (Ser.) Rehd. About 10,000 seeds from 900 crossing experiments were examined, 4500 of them for both filling of the grain and viability of the embryo. The results were compared with experimental reports and literature dating from 1753 to 1995. Apomictic reproduction was shown to be possible in all species of the section tested, but viable seed yields were only about 5% of those produced by xenogamy. This contradicts the hypothesis of Fagerlind (1940,1944,1945,1950) and Custafsson and Hakansson (1942), but supports the results of Matsson (1912) and Schwertschlager (1915). The number of viable seeds increased in the order apogamy, autogamy, geitonogamy to xenogamy. Reciprocal crossings showed significant differences in the number of seeds produced in the hip. This contradicts the hypothesis on the genomic constitution of the pentaploid Caninae with unbalanced heterogamy, as advocated by Hurst (1927) and Custafsson and Hakansson (1942). 相似文献
25.
26.
G. Werlemark M. Uggla H. Nybom 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(3-4):557-563
The dogroses, Rosa sect. Caninae, are polyploid and characterized by their unique meiosis with an unequal number of chromosomes in the male and female gametes.
The pollen cells have 7 chromosomes and the egg cells 21, 28 or 35 depending on the ploidy level of the species. The resulting
matroclinal inheritance was studied with both morphological and molecular markers in a pair of reciprocal crosses between
R. dumalis and R. rubiginosa (2n=35). A canonical discriminant analysis based on seven morphological characters showed only a minor overlapping between
the two progeny groups. In addition, the R. dumalis×R. rubiginosa offspring were more heterogeneous than the offspring from the reciprocal cross in each of the characters analysed. Eleven
RAPD markers specific for the R. dumalis parent and 10 RAPD markers specific for the R. rubiginosa parent were scored in the offspring. Each of the offspring exhibited either all, or all-but-one, of the seed parent markers.
The average number of pollen donor markers found in the offspring was 3.2 (R. dumalis×R. rubiginosa) and 2.7 (R. rubiginosa×R. dumalis). About half of the pollen donor markers were never transmitted to the progeny. This is, to our knowledge, the first time
the highly skewed chromosome distribution in Rosa sect. Caninae has been demonstrated with statistically evaluated morphological data and with molecular markers.
Received: 25 June 1998 / Accepted: 28 July 1998 相似文献
27.
记载了棘豆属一新组。目前该组包括二个种,它们是:黄穗棘豆和绿黄棘豆。过去,国内的学都将黄毛棘豆与黄穗棘豆等同。而文中作者认为黄毛棘豆是黄穗棘豆的一个变种。另外异色黄毛棘豆被作为变种处理。绿黄棘豆是一个中国新分布种。 相似文献
28.
ZHANG Wen-Ju QU Li-Jia GAO Wei GU Hong-Ya CHEN Zhang-Liang CHEN Jia-Kuan 《植物分类学报:英文版》1999,37(5):417-424
The ITS regions of 5 species in Aegilops sect. Sitopsis, the possible donors of Bgenome of common wheat, were amplified by PCR, cloned and sequenced. The phylogenetic
relationships among 5 species in Aegilops sect. Sitopsis were constructed based on ITS1 +
ITS2 sequences. The results demonstrated that Ae. speltoides was a distinct species in
Aegilops sect. Sitopsis. The average of the pairwise distances between Ae. speltoides and
the other four species was three times as high as that among the latter four. Ae. speltoides
was the earliest lineage of the section under question. Relationship between Ae. longissima
and Ae. sharonensis was the closest in Aegilops sect. Sitopsis. Sequence of ITS regioncould be used as a molecular marker to identify origin of B-genome in polyploid wheats. 相似文献
29.
Trititrigia is the intergeneric hybrid which is from the hybridization between Triticum durum Desf. and Elytrigia intermedium (Host) Nevski. Protoplasts of Trititrigia were isolated from the embryogenic cell suspension derived from immature inflorescence-induced calli of the hybrid F1. The first division occured 48 hr after plating in modified KM8p culture medium. The plating efficiency of protoplasts was 2% and 12.14% when they were cultured in liquid medium and agarose solidified medium, respectively. Clusters grew vigorously under these conditions. Fresh medium with decreased osmoticum was added 20–30 days after plating. When protoplast-derived calli, 2–4 mm in the size, were transferred step by step to different differentiation media, embryoids, green spots emerged and numerous plants regenerated eventually. 相似文献
30.
杨雁宾 《Plant Diversity》1980,2(3):1-3
酮(Xanthone)又称苯骈色原酮,是一类黄色或无色的酚性化合物,具有与黄酮类(Flavonoids)相似的颜色反应及色谱特性,因此曾被归入黄酮类讨论,但从其光谱特征看酮与黄酮是有区别的。 酮类主要分布于龙胆科(Gentianaceae)、藤黄科(Guttiferae)、桑科(Moraceae)和远志科(Polygalaceae)。但有一特殊例外:芒果甙(mangiferin-2-C-β-D-毗哺葡萄糖基-1,3,6,7-四羟基酮)不仅广布于被子植物的漆树科、藤黄科、豆科、山榄科、大风子科、百合科、鸢尾科、禾本科等,而且在蕨类植物的水龙骨科(Polypodiaceae)中也有发现。 相似文献