Seasonal variation of paulownia witches’-broom phytoplasma in paulownia trees and distribution of the disease in the Tohoku district of Japan     

Hitoshi Nakamura  Shigeto Ohgake  Norio Sahashi  Nobuyuki Yoshikawa  Takanori Kubono  Tsuyoshi Takahashi 《Journal of Forest Research》1998,3(1):39-42

Seasonal variation of paulownia witches’-broom (PWB) phytoplasma within different organs (leaves, branch and trunk bark and roots) in paulownia trees was investigated by the amplification of a PWB-specific DNA fragment by the polymerase chain reaction (PCR). In leaf samples, PWB phytoplasma was first detected in June and the incidence gradually increased. On the other hand, the PWB was detected at relatively low incidence in branch bark, trunk bark and roots and the incidence did not change among seasons. A survey of PWB in 27 fields in the Tohoku district of Japan showed that malformed flower buds were observed in paulownia trees in almost all of the fields. PWB-phytoplasma was also detected by PCR from paulownia trees in almost all of the fields in Iwate and Fukushima Prefectures. The frequencies of trees in which phytoplasma was detected by PCR were higher than those in which symptoms were observed. These results indicated that PCR amplification of a PWB-specific DNA fragment is an effective tool for practical diagnose and that PWB is widely distributed in the Tohoku district of Japan.  相似文献   

Enhancement of the biological resistance of wood by phenylboronic acid treatment     

Mustafa Kemal Yalinkiliç  Tsuyoshi Yoshimura  Munezoh Takahashi 《Journal of Wood Science》1998,44(2):152-157

Phenylboronic acid (PBA) was tested in terms of boron leachability from treated wood. In addition, the fungal and termiticidal efficacy of PBA-impregnated sugi (Cryptomeria japonica D. Don) wood was tested against the decay fungi Coriolus versicolor (L. ex Fr.) Quel. and Tyromyces palustris (Berk. et Curt) Murr., representing white-rot and brown-rot fungi, respectively, and the Formosan subterranean termite Coptotermes formosanus Shiraki. Ion chromatography analysis of hot water extracts of treated wood before and after leaching indicated that PBA is considerably resistant to water leaching, and saturation of the treatment solution increased the fixation ratio of boron in wood, whereas boric acid could not remain in wood impregnated even with the saturated solution. Decay test results revealed the excellent bioactive performance of PBA. Wood treated with 0.34% PBA solution was found resistant to both decay fungi, even after running-water leaching for 10 days and treatment with 1.00% PBA completely inactivated the Formosan subterranean termite for the leached specimens. Weight gain levels were 0.18% w/w (0.46kg/m³) and 0.99% w/w (2.49kg/m³) for these concentration levels, respectively, after being leached by running water. Contrary to the general belief that boron is a slow-acting toxicant against termites and unable to prevent mass loss of treated wood, PBA acted rapidly, and the mass loss caused by termites was low.This study was presented in part at the 47th annual meeting of the Japan Wood Research Society, Kochi, April, 1997  相似文献   

Estimating the spawning season of black sea bream Acanthopagrus schlegelii in Hiroshima Bay,Japan, from temporal variation in egg density     

Kawai  Kentaro  Fujita  Hiroki  Sanchez  Gustavo  Furusawa  Shuichi  Umino  Tetsuya 《Fisheries Science》2020,86(4):645-653

Fisheries Science - We aimed to determine the spawning period of black sea bream Acanthopagrus schlegelii in Hiroshima Bay, Japan, based on the distribution of its eggs, to assist in the resource...  相似文献   

Stock enhancement programme for black sea bream, Acanthopagrus schlegelii (Bleeker), in Hiroshima Bay, Japan: a review   总被引：1，自引：0，他引：1  

Enrique Blanco Gonzalez  Tetsuya Umino  & Kazuya Nagasawa 《Aquaculture Research》2008,39(12):1307-1315

This paper reviews the stock enhancement programme for black sea bream ( Acanthopagrus schlegelii ) in Hiroshima Bay. This bay is one of the biggest production areas for black sea bream in Japan, accounting for about 10% of the total catch of the species in this country in 2004. After intensive fishing pressure caused a drastic decline in the catch of the species in this bay in the 1970s, a stock enhancement programme was conducted in its northern part since 1982 to restore the depleted population. The number of black sea bream juveniles released in 1996 surpassed 9 million, representing the third main species stocked in Japan. Almost 1.4 million of these juveniles were released into Hiroshima Bay. The fast acclimatization of hatchery-reared juveniles released into the bay may have contributed to the recovery of landings in the late 1980s and 1990s. However, this recovery was accompanied by a reduction in the market price of black sea bream. Further studies to assess the effectiveness of the stock enhancement programme as well as the carrying capacity of Hiroshima Bay to maintain the stock of black sea bream at a stable, healthy level are desirable. The necessity of evaluating the secondary effects derived from using a reduced number of breeders as well as finding new markets are suggested.  相似文献   

Changes in plasma prolactin and growth hormone concentrations during freshwater adaptation of juvenile chum salmon (Oncorhynchus keta) reared in seawater for a prolonged period     

Tsuyoshi Ogasawara  Tetsuya Hirano  Toshio Akiyama  Shigeru Arai  Masatomo Tagawa 《Fish physiology and biochemistry》1989,7(1-6):309-313

Freshwater adaptability of chum salmon was examined in juvenile fish reared in seawater for 4 months. The fish, weighing about 40g, were transferred directly to fresh water in October, when their cohorts are migrating in the North Pacific Ocean. Plasma sodium concentration decreased from 167 mM in seawater to about 130 mM during the first 24h, and increased gradually during 2–7 days after the transfer. No immunoreactive prolactin (PRL) was detected in the plasma of the seawater-adapted fish nor during the first 24h in fresh water. Significant levels of PRL were detected after 2–3 days. The maximal level (2.6 ng/ml) was observed after 5 days and became undetectable again after 7 days; no significant correlation was seen between the changes in plasma sodium and PRL levels during the transfer. Plasma growth hormone levels were relatively constant, except for a significant decrease 12h after the transfer. Although plasma thyroxine levels were highly variable during the experiment, a significant decrease and an increase were observed 12h and 5 days after the transfer, respectively. The present study indicates that juvenile chum salmon retain hyperosmoregulatory ability even after prolonged rearing in seawater. Examination of turnover rates, rather than changes in plasma levels, seems to be essential to clarify the osmoregulatory roles of the hormones.  相似文献   

Molecular cloning of a cDNA encoding insulin-like androgenic gland factor from the kuruma prawn <Emphasis Type="Italic">Marsupenaeus japonicus</Emphasis> and analysis of its expression     

Kota Banzai  Noriko Ishizaka  Kiyoshi Asahina  Katsuyoshi Suitoh  Susumu Izumi  Tsuyoshi Ohira 《Fisheries Science》2011,77(3):329-335

  相似文献   

Evaluation of the temperature and relative humidity preferences of the western dry-wood termite <Emphasis Type="Italic">Incisitermes minor</Emphasis> (Hagen) using acoustic emission (AE) monitoring     

Yuliati Indrayani  Tsuyoshi Yoshimura  Yoshiyuki Yanase  Yoshihisa Fujii  Yuji Imamura 《Journal of Wood Science》2007,53(1):76-79

Twenty-four different combinations of six temperatures (15°, 20°, 25°, 30°, 35°, and 40°C) and four relative humidity (RH) (60%, 70%, 80%, and 90%) conditions were used for pseudergates of the western dry-wood termite Incisitermes minor (Hagen). The feeding activities of the termites were monitored by the detection of generated acoustic emission (AE) events from feeder wood blocks in a test chamber. Temperature and RH showed independent and interactive significant effects on the feeding activity of I. minor. The optimal temperature and RH conditions for the feeding activities were 35°C and 70%, respectively, and the optimal combinations were 35°C-70% and 35°C-80% with an exceptionally higher feeding activity at the combination condition of 30°C-70%.  相似文献   

Estimating the three-dimensional structure of canopy foliage based on the light measurements in a Betula ermanii stand     

Takuya Kubo  Tsuyoshi Kobayashi  Kyoko Kato  Seiichi Nishimura  Shigeru Uemura  Kiyomi Ono  Akihiro Sumida  Toshihiko Hara 《Agricultural and Forest Meteorology》2008,148(8-9):1293-1304

In order to more accurately evaluate the functional activity of forest stands by canopy production and evapotranspiration, we improved the methods for field measurements and statistical modeling to estimate foliage configuration (spatial distribution of leaves) while simultaneously reconstructing the three-dimensional photosynthetically active photon flux density (PPFD) distribution (PPFD pattern) in a forest canopy. By using a sensor (photodiode) array, a PPFD pattern was observed in summer 2002 under the canopy in an even-aged, pure stand of Japanese mountain birch Betula ermanii Cham. (17-years old) in Hokkaido, northern Japan. A Markov chain Monte Carlo (MCMC) sampling technique is developed such that a set of foliage configurations generated by the model referred to as the Gibbs foliage canopy (GFC) approximates the field-measured PPFD pattern. The posterior distribution of the foliage configurations is generated by the parallel tempering MCMC of eight independent series of foliage configurations. The GFC model generated the posterior distribution of the LAI estimates (mean 4.56) that appeared to be appropriate in comparison to other LAI estimates of the B. ermanii stand based on the indirect and nondestructive methods by LAI-2000 (LAI = 3.43) and litterfall traps (LAI = 5.56) because they could be under- and overestimated, respectively. Our evaluations of the canopy production and evapotranspiration rates suggest that the relationship between LAI and canopy functions was not very simple because it depended on the nonlinear functional forms of the leaf responses of photosynthesis and transpiration to PPFD. The current study demonstrates an application of MCMC techniques that can generate a set of possible structures of unobserved/unobservable objects based on the high-resolution dataset obtained by some indirect (or remote-sensing) methods.  相似文献   

Adjunct ambrisentan therapy had clinical benefits in 5 dogs with sildenafil-refractory pulmonary hypertension     

Seijirow Goya  Tomohiko Yoshida  Shigeharu Sennba  Tsuyoshi Uchide  Ryou Tanaka 《The Canadian veterinary journal. La revue veterinaire canadienne》2022,63(5):497

Although sildenafil is used in dogs with severe pulmonary hypertension, they sometimes become resistant and clinical signs deteriorate over time. The objective of this study was to determine the benefits of adjunct ambrisentan therapy in dogs with sildenafil-refractory pulmonary hypertension. In 5 dogs with severe pulmonary hypertension with deteriorating clinical signs despite ongoing sildenafil treatment, adding ambrisentan improved appetite, activity, and respiratory functions. Although peak tricuspid valve regurgitation velocity, as measured by Doppler echocardiography, did not necessarily decrease after ambrisentan administration, there was improved partial pressure of arterial oxygen and the alveolar-arterial oxygen gradient, with no apparent side effects. We concluded that ambrisentan has potential as an adjunct treatment in dogs with pulmonary hypertension that are refractory to sildenafil therapy.Key clinical message:Ambrisentan improved clinical signs in dogs with sildenafil-refractory pulmonary hypertension.  相似文献   

Biofilm formation and resistance to bactericides of <Emphasis Type="Italic">Pseudomonas syringae</Emphasis> pv. <Emphasis Type="Italic">theae</Emphasis>     

Tsuyoshi Tomihama  Yatsuka Nishi  Kei Arai 《Journal of General Plant Pathology》2007,73(3):193-196

Biofilm-grown cells of Pseudomonas syringae pv. theae (P.s.theae) wild-type strain K9301 on abiotic surface had remarkable resistance to kasugamycin in comparison to planktonically grown cells; however, the biofilm-grown cells of K9301 had the same sensitivity to copper sulfate. Because both the lesser biofilm-forming strain K9301S3 and enhanced biofilm-forming strain K9301-6 also had remarkable biofilm resistance to kasugamycin just as K9301 did and because epigallocatechin gallate, which enhanced biofilm formation of P.s.theae, had no effect on biofilm resistance to kasugamaycin, the degree of biofilm formation was not correlated with the antibiotic susceptibilities. In addition, K9301 and K9301S3 had less sensitivity to kasugamycin but had high sensitivity to copper sulfate on nonwounded leaf surfaces. These results indicate a possibility that the mechanism of P.s.theae biofilm resistance to bactericide functions on both abiotic and nonwounded leaf surfaces.  相似文献