Powdery Mildew of Prairie Gentian: Characteristics,Molecular Phylogeny and Pathogenicity   总被引：3，自引：0，他引：3  

OKAMOTO  Jun  LIMKAISANG  Saranya  NOJIMA  Hidenobu  TAKAMATSU  Susumu 《Journal of General Plant Pathology》2002,68(3):200-207

In March 1999, we found prairie gentian (Eustoma grandiflorum) infected with powdery mildew in a greenhouse in Oita Prefecture, Japan. Morphological observation revealed that the causal fungus belongs to the mitosporic genus Oidium subgenus Pseudoidium [teleomorph: Erysiphe sensu Braun and Takamatsu (2000)]. Precise taxonomic position of the fungus, however, is uncertain due to lack of the perfect stage. We determined the nucleotide sequence of the rDNA ITS region of the fungus. Comparison of the sequence with those obtained from DNA databases of this fungal group revealed that the sequence is identical to those of powdery mildews from garden four-o'clock (Mirabilis jalapa) and broad bean (Vicia faba). Inoculation of an isolate from garden four-o'clock caused mildew on prairie gentian and broad bean, suggesting that the prairie gentian mildew originates from garden four-o'clock or broad bean. Molecular phylogenetic analysis indicated a close relationship of this fungus to Erysiphe baeumleri on Vicia spp. and E. trifolii on Trifolium pratense. From these results, we propose that prairie gentian mildew diverged from a Fabaceae-parasitic ancestor. Received 14 March 2002/ Accepted in revised form 28 May 2002  相似文献   

Gene constitution of South-East Asian native chickens, commercial chickens and jungle fowl using polymorphisms of four calpain genes     

Fumihiko OKUMURA  Takeshi SHIMOGIRI  Kotaro KAWABE  Shin OKAMOTO  Masahide NISHIBORI  Yoshio YAMAMOTO  Yoshizane MAEDA 《Animal Science Journal》2006,77(2):188-195

The gene constitution of polymorphisms of the four calpain genes (µ‐calpain, m‐calpain, p94, and µ/m‐calpain) were analyzed in South‐East Asian native chickens, White Leghorn and Broiler commercial chickens, and Red and Green jungle fowl. Polymorphisms were detected at all loci in chickens and Red jungle fowl, but only for CAPN1 (µ‐calpain gene) in Green jungle fowl. CAPN2 and CAPN1.5 are linked on chicken chromosome 3, and the genotype for these loci were treated as haplotype. Some combinations of calpain loci were tested using principal component analysis, and the best combination (CAPN1, CAPN3, and CAPN1.5) was determined. The proportion of polymorphic loci (P_poly) and heterozygosity (H?) were 1.00 and 0.316–0.465 in domestic chickens and red jungle fowl, and 0.33 and 0.137 in Green jungle fowl, respectively. G_ST values suggested that the degree of subdivision among native chickens was relatively low except for Thailand, which was highest. Pair‐wise F_ST testing, dendrogram and principal component analysis from the results of calpain loci showed that the four South‐East Asian native and commercial chicken populations were close genetically.  相似文献   

Preliminary experiments on mechanical stretch-induced activation of skeletal muscle satellite cells in vivo     

Tomowa SAKATA  Ryuichi TATSUMI  Michiko YAMADA  Sei-Ichi SHIRATSUCHI  Shinpei OKAMOTO  Wataru MIZUNOYA  Akihito HATTORI  Yoshihide IKEUCHI 《Animal Science Journal》2006,77(5):518-525

We have shown in vitro that mechanical stretch triggers activation of quiescent satellite cells of skeletal muscle to enter the cell cycle through an intracellular cascade of events including nitric oxide (NO) synthesis that results in the release of hepatocyte growth factor (HGF) from its extracellular association and its subsequent presentation to signaling receptors. In order to explore the activation mechanism in vivo, stretch experiments were conducted in the living animal using our suspension model developed. This system used the weight of the hind portion of rats to stretch the inside muscles of the left hind limb suspended for a period of 0.5–2.0 h. At the end of the stretch period, the rats received an intraperitoneal injection of bromodeoxyuridine followed by immunocytochemistry for its incorporation as an index of satellite cell activation in vivo. Depending on the period of stretch, bromodeoxyuridine labeling was increased significantly over the contralateral unstretched leg or control muscle from untreated rats. A stretched muscle extract prepared from the 2 h stretched tissue by incubating it in PBS, showed the active form of HGF as revealed by immunoblotting and it could stimulate the activation of unstretched satellite cells. Also, administering NO synthase inhibitor L‐NAME prior to muscle stretch abolished the stretch activation of satellite cells. Therefore, the results from these experiments demonstrate that stretching muscle triggers NO synthesis and HGF release, which could activate satellite cells in vivo.  相似文献   

A new viral epizootic of Anguilla japonica Temminck and Schlegel     

T. SANO  N. OKAMOTO  T. NISHIMURA 《Journal of fish diseases》1981,4(2):127-139

Abstract. In 1969, a new kind of epizootic occurred among eels in Japan and virological investigation was initiated. A new virus designated eel virus european (EVE) was isolated and biological, cytological, serological tests and infectivity trials were carried out. In its CPE on RTG-2 cells and additionally in its biological properties and particle size, EVE was found to be similar to infectious pancreatic necrosis virus (IPNV). Serologically, EVE was similar to the ď Honnincthun, France, strain of IPNV. However, infectivity trials showed that EVE and IPNV differed; EVE killed Japanese eels Anguilla japonica but not rainbow trout fry Salmo gairdneri , while IPN virus killed rainbow trout fry but not eels. We consider EVE to be the primary agent causing the new epizootic and propose the name viral kidney disease for the resulting clinical condition.  相似文献   

Relationship between fish growth rate and progression of artificially induced erythrocytic inclusion body syndrome in coho salmon, Oncorhynchus kisutch (Walbaum)     

K. TAKAHASHI  N. OKAMOTO  A. KUMAGAI  M. MAITA  J. S. ROHOVEC  Y. IKEDA 《Journal of fish diseases》1994,17(1):77-83

Abstract. Studies were conducted to clarify the relationship between growth rate and disease progression of erythrocytic inclusion body syndrome (EIBS) in artificially infected coho salmon, Oncorhynchus kisutch (Walbaum). In the diseased state, the haematocrit values decreased and the number of erythrocytes with inclusions was higher in faster growing fish. Rapid growth was accompanied by an abundance of immature erythrocytes, which had the greatest incidence of inclusion bodies.  相似文献   

Immunolocalization of sex steroid receptors in the epididymis and ductus deferens of immature and mature Japanese Quail, Coturnix Japonica     

Hanako NISHIZAWA  Toshikazu OKAMOTO  Yukinori YOSHIMURA 《Animal Science Journal》2002,73(5):339-346

The goal of this study was to determine whether in the Japanese quail the male genital tract contains receptors for progesterone, androgen and estrogen (PR, AR and ER, respectively), which have significant roles in reproductive functions, and whether their localization changes during sexual maturation. The epididymis and ductus deferens (middle and ampulla regions) of immature (approximately 30-day-old) and mature male Japanese quail were collected and frozen sections of them were immunostained for PR, AR and ER. The immunoreaction products for AR and PR were found in the nuclei of epithelial cells in the efferent ductules, epididymal duct, and the middle and ampulla regions of the ductus deferens of mature and immature birds. In the mature birds, the epithelial cells of the efferent ductules, epididymal duct, and the middle and ampulla regions of the ductus deferens were positive for ER, although some of the cells in the ductus deferens were negative. The epithelial cells of the ductules in the epididymis stained positive for ER, but the immunoreactions were negligible in the ductus deferens of immature birds. These results suggest that the epididymis and ductus deferens in quail possesses PR, AR and ER receptors. Each receptor is expressed before sexual maturation, although enhancement of ER expression may occur during maturation.  相似文献   

Grassland Degradation,Construction and the Econmic-technological Strategies of Sustainable Development of Grassland-agriculture     

OKAMOTO Chinobu 《东北农业大学学报(英文版)》2004,(1)

NaturalgrasslandintheWestofNortheasternChinaislocatedin41°0'-43°5'Nlatitudeand117°0'-127°5'Elongitude.ItlaystheLiaoRiverVal鄄ley,theSonghuaRiverValleyandNenRiverValley.About130yearsago,thisgrasslandhadrichnaturalgrasslandresources,includingmeadowandswampmeadow,andwasnumerically26.67millionsinhectareofnaturalgrasslands.Inthelightofourinfer鄄ence[1-3].Therewereabout1000speciesofseedplantsinthisgrasslandinthatperiodandtheybelongmain鄄lytoPoaceae,Astraceae,Cyperaceae,andFabaceae[4].1Me…  相似文献   

A new thiamine derivative,S-benzoylthiamine O-monophosphate     

WADA T  TAKAGI H  MINAKAMI H  HAMANAKA W  OKAMOTO K  ITO A  SAHASHI Y 《Science (New York, N.Y.)》1961,134(3473):195-196

S-Benzoylthiamine O-monophosphate has been synthesized, and its physicochemical and biological properties have been investigated. It is a stable crystalline substance, it exerts thiamine activity approximately equivalent to that of thiamine hydrochloride in thiamine-requiring microorganisms, and it is easily absorbed in organisms, particularly by oral administration.  相似文献   

Traits of shattering resistant buckwheat ‘W/SK86GF’     

Tatsuro Suzuki  Yuji Mukasa  Toshikazu Morishita  Shigenobu Takigawa  Takahiro Noda 《Breeding Science》2012,62(4):360-364

Seed shattering is a significant problem with buckwheat, especially at harvesting time. Several reports have shown that a green-flower mutant of buckwheat, such as W/SK86GF, has a strong pedicel. Although a strong pedicel may provide some resistance to shattering in the field, no study has thoroughly examined this issue. In this paper, we demonstrate that a W/SK86GF has shattering resistance by comparing the degrees of shattering of W/SK86GF and Kitawasesoba (leading variety of Hokkaido with non-green-flower traits) through a test for four years, including a typhoon hit year in the field. In a non-typhoon year, the shattering seed ratio (shattering seed weight/(yield + shattering seed weight) × 100) of W/SK86GF at maturing time +15 days (+15D) was lower than that of Kitawasesoba. In a typhoon hit year, the shattering seed ratios of Kitawasesoba at maturing time and +15D were surprisingly high, 14.4 and 21.1%, respectively. On the other hand, those of W/SK86GF were only 3.08% and 2.57%, respectively; indicating W/SK86GF is promising as a shattering resistant line even in a typhoon hit year. From these results, shattering resistance of W/SK86GF can be evaluated after maturing time such as +15D and pedicel strength would confer W/SK86GF a shattering resistant trait.  相似文献   

FCV-VBS isolated from cats with typical symptoms caused VSD in experimental cats     

Ohe K  Takahashi T  Hara D  Hara M 《Veterinary research communications》2008,32(2):145-158

Commercially available vaccines have been used widely to prevent feline calicivirus infection (FCI). However, with their widespread use, field strains, which are weakly cross-reactive with the live-virus vaccine strain F9, have posed the problem of vaccine breakdown. Recently the existence of FCV—associated virulent systemic disease (VSD) has been published. But their molecular diversity, antigenic mutations and physicochemical property have not been sufficiently clarified. Thus, we experimentally gave the vaccine breakdown strain (VBS) H10 to cats that had been inoculated with an F9 live vaccine. After the administration of strain H10, vaccinated cats (1 through 4) had no respiratory symptoms, whereas the non-vaccinated cat 5 showed clinical symptoms such as a fever of over 40°C, loss of vitality, decreased appetite, diarrhea, and nasal discharge after receiving strain H10, and died. Lethal FCV is rare, and may be a virulent systemic disease (VSD)—inducing strain. This is the initial report on VSD in Japan. It has been reported that symptoms of VSD were similar in vaccinated and nonvaccinated cats on experimental infection. However, no VSD-like symptoms developed, and the incidence of the disease varied depending on the presence or absence of vaccination, suggesting that there are two mechanisms of vaccine breakdown: one is associated with the vaccine immunity level, and the other is not. The characteristics of the VBS revealed were: (1) the duration of virus excretion was short when the originally carried antibody titer before virus challenge was high, (2) the excreted viral molecular species varied daily, not being limited to a specific species with time, and (3) the acquired physicochemical properties did not persist, and altered daily. FCV-VBS alters the molecular species and physicochemical properties daily due to the reduction of host immunity, which may lead to VSD.  相似文献