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1.
With the aim of making clear the boundaries between species in thePoa acroleucahisauchii-nipponica aggregate, chromosomes and morphological features of 746 collections gathered from 125 localities in Japan were examined.
For morphological observations, the voucher specimens of 95 collections whose chromosome numbers were reported previously
(Tateoka, 1985) were also used. Tetraploids (2n=28) and hexaploids (2n=42), as well as a few pentaploids which were the hybrids
between 4× and 6×, were found. By examining morphological features of these collections, two groups were recognized in tetraploids
and one in hexaploids. The two tetraploid groups corresponded toPoa acroleuca Steud. andP. hisauchii Honda, and the hexaploid group toP. nipponica Koidz. It was confirmed that the hairiness on the internerve surface of lemma, ligule hairiness and the length ratio of anther/
lemma are the most important features for discriminating between these species; panicle shape, leaf shape and anther length
are also helpful for the identification. The ambiguity of the boundaries between species which was hitherto present in the
taxonomy of this species aggregate was unrelated to the creation of nature itself but was attributable to the insufficiency
of our research work. 相似文献
2.
Tuguo Tateoka 《American journal of botany》1964,51(5):539-543
Three distinct types of embryo have been found in 18 species of the genus Oryza. Type 1 is characterized by lateral fusion of the epiblast and the scutellum and also by the development of auricles. Type 2 has no auricle, and the epiblast is not laterally fused with the scutellum. Type 3 has a cleft between the lower part of the scutellum and the coleorhiza, a long epiblast which is free from the scutellum, and lacks auricles. Type 1 has been found in 13 species of section Sativae, Type 2 in 4 species of sections Granulatae and Coarctatae, and Type 3 in O. coarctata only. The results indicate that species of section Sativae are more or less closely related, while section Coarctatae is a heterogeneous group. A new section, Ridleyianae, has been described for Oryza ridleyi and some other species. Oryza coarctata has unique features in embryo structure, morphology and leaf anatomy, and this species has been moved from the genus Oryza to a separate genus, Sclerophyllum, which is here revived. 相似文献
3.
Pyrolysates of cyanocobalamin, thiamine hydrochloride, riboflavin, pyridoxine hydrochloride, and ascorbic acid were tested for mutagenicity in the histidine-requiring mutants Salmonella typhimurium TA98 and TA100. Each vitamin was sealed in a glass tube and heated at 100-600 degrees C in a muffle furnace. Methanol-chloroform extracts of the pyrolysate of each vitamin tested did not show any mutagenicity in either TA98 or TA100 without rat liver 9000 x g supernatant fraction (S9) added. In the presence of S9, the B-group vitamins (cyanocobalamin, thiamine hydrochloride, riboflavin, and pyridoxine hydrochloride) were all mutagenic in TA98 and TA100, with the highest activity among the vitamins tested found in the pyrolysate of cyanocobalamin. The pyrolysate of 0.25 mumole cyanocobalamin produced 3200 revertants, while the pyrolysates of 0.25 mumole thiamine hydrochloride and riboflavin produced only 910 revertants, and the pyrolysate of pyridoxine hydrochloride did not show any mutagenicity at that amount. The mutagenicity was generally more active to TA98 than to TA100, indicating that frameshift-type mutagens were contained in the pyrolysates. The pyrolysate of ascorbic acid did not show any mutagenic activity in either TA98 or TA100 under the present experimental conditions. 相似文献
4.
Tuguo Tateoka 《Journal of plant research》1984,97(2):247-270
Chromosome counts were made for a total of 540 collections ofCalamagrostis hakonensis from 66 localities ranging from Kyushu to Hokkaido. Distribution and habitat preferences of the cytotypes involved are described.
Sympatric occurrence of tetraploids (=semidiploids, 2n=28) and higher polyploids, as well as that of septaploids and plants
at hexaploid and/or octoploid levels, was confirmed in several localities, and mixtures of hexaploids and octoploids within
a population were frequently observed. Plants at hexaploid and octoploid levels were the most abundant and widespread. An
examination of pollen of the voucher specimens showed that tetraploids (amphimictic) had good pollen, while higher polyploids
(apomictic) were generally devoid of pollen and very rarely produced moderately good pollen, the grains of higher polyploids
being larger than those of tetraploids. Distributions of tetraploids and higher polyploids were more precisely delineated
through an examination of pollen of many herbarium specimens. In relation to the processes by which the complicated internal
structure ofC. hakonensis has been established, the following subjects are discussed: infraspecific hybridization between ecotypically differentiated
populations, enrichment of variability through occasional sexual reproduction expected in plants with more than 2n=42, persistence
of the variants by apomictic reproduction, and probable roles of some extinct taxa. 相似文献
5.
Kaori Kikuchi Yoshiharu Itoh Ryoko Tateoka Atsuko Ezawa Kenjiro Murakami Toshimitsu Niwa 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(20):1662-1668
We applied the metabolomic analysis of comprehensive small-molecular metabolites using liquid chromatography/electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS) and principal component analysis to identify uremic toxins accumulated in the serum of chronic renal failure (CRF) rats. CRF rats were produced by 5/6-nephrectomy. Indoxyl sulfate was demonstrated to be the first principal serum metabolite which differentiates CRF from normal, followed by phenyl sulfate, hippuric acid and p-cresyl sulfate. Then, we measured the serum levels of indoxyl sulfate, phenyl sulfate, hippuric acid and p-cresyl sulfate by the selected reaction monitoring (SRM) of LC/ESI-MS/MS, and demonstrated that these serum levels were markedly increased in CRF rats as compared with normal rats. As creatinine clearance decreased, the serum levels of the metabolites increased. 相似文献
6.
Tuguo Tateoka 《Journal of plant research》1978,91(3):141-171
Relationships amongCalamagrostis longiseta var.longiseta, C.l. var.longe-aristata andC. fauriei, which are principally at the 2n=28 chromosome level, were studied mainly on the basis of population samples. The populations
comprised (1) “pure” populations of each ofC.l. longiseta, C.l. longe-aristata andC. fauriei and (2) populations showing a gradation fromC.l. longiseta toC. fauriei via the intermediateC.l. longearistata and fromC.l. longiseta toC.l. longe-aristata. Hybridization betweenC.l. longiseta andC. fauriei was estimated to be ultimately related to the geneses of the population structures detected, and it was concluded thatC.l. longe-aristata must be of hybrid origin betweenC.l. longiseta andC. fauriei. Populations showing a gradation fromC.l. longiseta toC.l. longe-aristata were regarded to have been brought about by the extinction ofC. fauriei from the hybridizing population coupled with the change of environments and also by the secondary contact betweenC.l. longiseta and plants ofC.l. longe-aristata migrating from the area that produced it. No significant reduction of pollen fertility and seed productivity was found inC.l. longe-aristata. Based on the results of population analyses, the delimitation of the taxa concerned was made clearer. The examination of
herbarium specimens showed that the range ofC.l. longe-aristata considerably exceeds the overlapping area of the present ranges ofC.l. longiseta andC. fauriei. The three taxa were deviated ecologically, and “pure” populations ofC.l. longe-aristata were found on several damp subalpine fields in central and northern Honshu that seemed to represent the most suitable niche
for this taxon. It was estimated thatC.l. longe-aristata would evolve into a new good species if the future organism-environment interactions are favorable for it. 相似文献
7.
The internal structure of theCalamagrostis langsdorffii-sachalinensis complex in Shikoku was examined on the basis of a number of new collections. Chromosome counts disclosed the occurrence of
the following entities: 6X and 8X, as well as some aneuploids, ofC. longsdorffii; 6X ofC. sachalinensis; 6X and 8X of the intermediates between these two species. The examination of pollen of these collections and the herbarium
specimens showed that all of them may be apomictic in seed formation and that the sexual tetraploids of the pertinent complex
may not be distributed in Shikoku. Details of morphological features of the collections were analyzed, and the intermediacy
in morphology of the group “intermediate” was confirmed by the distance diagram method. The collections ofC. langsdorffii from Shikoku generally showed an awn longer than that of the collections from Honshu and Hokkaido. On the basis of these
and some other observations, relationships of the strains extant in Shikoku were discussed. For the derivation of the present-day
composition of the pertinent complex, an hypothesis which is founded on the presumption of a past occurrence of sexual tetraploids
of bothC. langsdorffii andC. sachalinensis in Shikoku has been advanced. 相似文献
8.
Tuguo Tateoka 《Journal of plant research》1976,89(2):99-114
Chromosome counts for 783 collection ofCalamagrostis in Japan are reported. These include the first record forC. tashiroi and the reports of new cytotypes inC. stricta, C. hakonensis andC. longiseta. The geographical distribution of different cytotypes ofC. langsdorffii andC. hakonensis is outlined. Counts are also reported for a number of “intermediates” which are supposed to be interspecific hybrids or hybrid
derivatives. A summary of chromosome counts for JapaneseCalamagrostis so far recorded is tabulated. No diploid plants with 2n=14 chromosomes are found. The tetraploid taxa, which are plentiful
and seem to have adaptively radiated in Japan, jack any sign suggestive of their recent origin from the diploids. It is suggested
that plant with 2n=28 (4X in the traditional sense) may be regarded as semidiploid and having that behavior, and that speciation
ofCalamagrostis in Japan has occurred principally at this chromosome level. Speciation by means of amphiploidy may have been scarce. It is
also suggested that hybridization and polyploidy have greatly contributed to the formation of complicated internal structure
of various species. 相似文献
9.
Soya H Deocaris CC Yamaguchi K Ohiwa N Saito T Nishijima T Kato M Tateoka M Matsui T Okamoto M Fujikawa T 《Bioscience, biotechnology, and biochemistry》2008,72(9):2476-2480
The extract of the stem bark of Siberian ginseng, Acanthopanax senticosus Harms (ASH), is believed to play a body-coping role in stress through a brain noradrenergic mechanism. The present study was carried out to investigate the effect of ASH on the neuronal activation patterns of c-Fos expression in the rat brain. With ASH administration, c-Fos accumulated in both the supraoptic nuclei (SON) and paraventricular nuclei (PVN), which regulate stress response. Only the caudal regions in the nucleus of the solitary tract (NTS), a locus innervating both the SON and PVN, were activated. Such a neuro-anatomical pattern associated with ASH suggests the possible involvement of these stress-related brain loci. 相似文献
10.