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131.
Fatma F. Abdel-Motaal Soad A. El-zayat Yuki Kosaka Magdi A. El-Sayed Rumi Kashima Yukie Maeda Mortada S. M. Nassar Shin-ichi Ito 《Journal of General Plant Pathology》2010,76(2):102-111
The antifungal activities of hyoscyamine and scopolamine, major alkaloids extracted from the desert plant Hyoscyamus muticus, against two rice pathogens, Magnaporthe oryzae and Rhizoctonia solani, were studied. The minimum inhibitory concentration of hyoscyamine that resulted in distinctive inhibition (MIC50) was 1 μg/ml for both fungi. Exposure to hyoscyamine caused the leakage of electrolytes from the mycelia of both fungi. Hyoscyamine
(>1 μg/ml) irreversibly delayed or inhibited conidial germination and appressorium formation in M. oryzae grown on polystyrene plates. Hyoscyamine effectively inhibited the attachment of conidia to the surface of rice (Oryza sativa) leaves and inhibited appressorium formation on the leaves. A high concentration of scopolamine (1000 μg/ml) also delayed
or inhibited conidial germination in M. oryzae, but conidial germination was restored after washing the conidia with water. Antifungal activity of hyoscyamine was reduced
by scopolamine. Magnaporthe oryzae infection was significantly suppressed (by >95%) in leaves of intact rice plants treated with hyoscyamine (10 μg/ml). Moreover,
10 μg hyoscyamine/ml significantly reduced the disease severity index for sheath blight to ≤0.2, when compared with the disease
index of control plants (>7.0). Hyoscyamine (>20 μg/ml) completely inhibited sclerotial germination and development of R. solani by delaying the initiation, maturation, and melanization of the sclerotia. These results suggest that tropane alkaloids may
be useful for controlling blast and sheath blight diseases of rice and for studying the mechanisms that regulate conidial
germination in M. oryzae and sclerotial germination and development in R. solani. 相似文献
132.
Fatma F. Abdel-Motaal Magdi A. El-Sayed Soad A. El-Zayat Mortada S. M. Nassar Shin-ichi Ito 《Journal of General Plant Pathology》2010,76(5):358-361
Floral rot of Egyptian henbane (Hyoscyamus muticus L.) was found on potted plants in a greenhouse in Yamaguchi city, Japan, in the late summer of 2008 and 2009. The symptoms
were identical to those of rots caused by Choanephora species. The pathogen was isolated and identified as C. cucurbitarum (Berkeley and Ravenel) Thaxter. This new disease was named Choanephora rot (Kougai-kabi-byo) of Egyptian henbane. 相似文献
133.
Kazuhiko Masaka Hiroyuki Torita Hirokazu Sato Hirokazu Kon Hajime Sato Minoru Fukuchi 《Journal of Forest Research》2010,15(5):341-346
To demonstrate the effect of excess soil moisture on the decline of a coastal Pinus thunbergii stand in Oshamanbe, southwestern Hokkaido, Japan, soil moisture content was monitored for 4 years. The saturated hydraulic
conductivities (K
S) of different soil types (coastal sand, supplied topsoil, and buried concreted andosol) and the distribution of the buried
concreted andosol layer were investigated. We also examined needle length to verify the real-time response of P. thunbergii to excess soil moisture. Soil moisture content at the heavily damaged site was more heterogeneous than that at the slightly
damaged site, and a sensor near the ground always reported a higher soil moisture content at the heavily damaged site than
at the slightly damaged site. The buried concreted andosol layer was always found at the heavily damaged site. The K
S of the andosol layer was 10−5, suggesting that this layer is less permeable to water, leading to excess soil moisture at this site. P. thunbergii needles from the heavily damaged site were shorter than those from the slightly damaged site, possibly because of water stress.
Together with other symptoms observed at the study sites, i.e., crown dieback and intense lateral growth, this information
leads us to conclude that the decline of P. thunbergii stands at the heavily damaged site in Oshamanbe was caused by excess soil moisture due to the less permeable buried concreted
andosol layer. 相似文献
134.
Yoshio Kijidani Tetsuya Hamazuna Satoshi Ito Ryushi Kitahara Shinsuke Fukuchi Nobuya Mizoue Shigejiro Yoshida 《Journal of Wood Science》2010,56(1):1-6
The lumber from sugi plantations in Japan displays large intra- and intertree variation in mechanical properties, even within
a stand. These variations seem to be induced by the effects of the characteristics of cultivars as well as the effects of
growth traits on mechanical properties. Therefore, the effects of growth traits on mechanical properties per cultivar need
to be precisely examined. In this study, we focused on the effects of growth traits, especially height-to-diameter ratio (H/D
ratio), on stem stiffness per cultivar. Sixteen cultivars were classified into three groups according to the relationships
between stem stiffness and growth traits. In cultivars that showed a close correlation between growth traits and stem stiffness,
it was assumed that stem stiffness could be controlled to a certain extent by silvicultural practices using the H/D ratio
as an indicator. In cultivars that showed a weak correlation between growth traits and stem stiffness, selecting cultivars
for the production of logs with higher mechanical properties seemed to be effective; in this study, Kumotoshi, Tanoaka, and
Edanaga were found to be suitable. Tree age and site index may be important factors for producing wood with higher mechanical
properties. 相似文献
135.
Nuclear Replacement of In Vitro‐Matured Porcine Oocytes by a Serial Centrifugation and Fusion Method
N Maedomari K Kikuchi T Nagai M Fahrudin H Kaneko J Noguchi M Nakai M Ozawa T Somfai LV Nguyen J Ito N Kashiwazaki 《Reproduction in domestic animals》2010,45(4):659-665
The objective of the present study was to establish a method for nuclear replacement in metaphase‐II (M‐II) stage porcine oocytes. Karyoplasts containing M‐II chromosomes (K) and cytoplasts without chromosomes (C) were produced from in vitro‐matured oocytes by a serial centrifugation method. The oocytes were then reconstructed by fusion of one karyoplast with 1, 2, 3 or 4 cytoplasts (K + 1C, K + 2C, K + 3C and K + 4C, respectively). Reconstructed oocytes, karyoplasts without fusion of any cytoplast (K) and zona‐free M‐II oocytes (control) were used for experiments. The rates of female pronucleus formation after parthenogenetic activation in all groups of reconstructed oocytes (58.2–77.4%) were not different from those of the K and control groups (58.2% and 66.0%, respectively). In vitro fertilization was carried out to assay the fertilization ability and subsequent embryonic development of the reconstructed oocytes. The cytoplast : karyoplast ratio did not affect the fertilization status (penetration and male pronuclear formation rates) of the oocytes. A significantly high monospermy rate was found in K oocytes (p < 0.05, 61.6%) compared with the other groups (18.2–32.8%). Blastocyst formation rates increased significantly as the number of the cytoplasts fused with karyoplasts increased (p < 0.05, 0.0–15.3%). The blastocyst rate in the K + 4C group (15.3%) was comparable with that of the control (17.8%). Total cell numbers in both the K + 3C and K + 4C groups (16.0 and 15.3 cells, respectively) were comparable with that of the control (26.2 cells). Our results demonstrate that a serial centrifugation and fusion (Centri‐Fusion) is an effective method for producing M‐II chromosome transferred oocytes with normal fertilization ability and in vitro development. It is suggested that the number of cytoplasts fused with a karyoplast plays a critical role in embryonic development. 相似文献
136.
Ito D O'Brien TD Modiano JF 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(4):494-498
Background: Cytoplasmic fragments derived from fragile neoplastic lymphocytes are common in samples of lymph nodes collected from dogs with lymphoma. These cytoplasmic fragments interfere with accurate gating of target cells and quantification protocols used for flow cytometry because of their variable size and expression of lymphoid cell surface antigens on their membranes. Objective: The aim of this study was to develop a method to efficiently exclude cytoplasmic fragments from flow cytometric analysis of canine lymph nodes in which lymphoma was present. Methods: Single‐cell suspensions of neoplastic cells were prepared from biopsy samples and fine‐needle aspirates of lymph nodes from 23 dogs with lymphoma. Suspensions were stained using a violet laser‐excitable (405 nm) membrane‐permeable DNA‐binding fluorescent dye (DyeCycle Violet [DCV]), incubated with antibodies against CD3, CD5, CD21, CD22, and CD45, and then stained with 7‐amino‐actinomycin D (7‐AAD), an argon‐excitable (488 nm) membrane‐impermeable DNA‐binding fluorescent dye. Multiparameter flow cytometry was used for analysis based on selective uptake and laser‐activated fluorescence of these dyes. Results: Cytoplasmic fragments, which were DCV‐negative and CD45‐positive, and dead cells, which were positive for 7‐AAD, were efficiently separated from neoplastic cells. Conclusion: Staining with DCV is a useful method to improve flow cytometric gating methods and quantitative analyses of lymph node samples from dogs with lymphoma. 相似文献
137.
Miori Kishimoto Sa-Hun Pae Naoyoshi Muroya Hirokazu Watarai Hiroshi Anzai Ki-Ja Lee Junichiro Shimizu Motoki Sasaki Kazutaka Yamada 《Journal of veterinary science (Suw?n-si, Korea)》2010,11(1):89-91
Caudolateral curvilinear osteophyte (CCO), an osteophyte at the site of joint capsule attachment on the caudal aspect of the femoral neck, has been advocated as a radiographic criterion for coxofemoral subluxation. The correlation between the presence of CCO on radiographs (radiographic-CCO), the size of the CCO (CCO index) on three-dimensional computed tomographic (CT) images, and hip evaluation using transverse CT images was assessed in 22 Border Collies. CCOs were detected on the radiographs and CT images of 32% and 100% femurs, respectively. The CCO index correlated significantly with radiographic-CCO, but a large CCO index did not necessarily imply that the CCO was visible on radiographs. Hence, radiographic-CCO findings should be used cautiously in hip evaluation of Border Collies. 相似文献
138.
Growth variability of Pacific saury Cololabis saira larvae under contrasting environments across the Kuroshio axis: survival potential of minority versus majority 下载免费PDF全文
Akinori Takasuka Kirara Nishikawa Hiroshi Kuroda Takeshi Okunishi Yugo Shimizu Hideo Sakaji Shin‐Ichi Ito Tadashi Tokai Yoshioki Oozeki 《Fisheries Oceanography》2016,25(4):390-406
Growth variability was examined for Pacific saury Cololabis saira larvae under contrasting environments across the Kuroshio axis, based on samples collected during the winter spawning season in 2013 and 2014. The growth rate index (residual of the otolith marginal 3‐day mean increment width from the linear regression on knob length) of larvae was compared among three areas: the inshore side of the Kuroshio axis, the Kuroshio axis, and the offshore side of the Kuroshio axis in relation to sea surface temperature (SST), salinity (SSS) and chlorophyll‐a (CHL) concentration. The larvae were more densely distributed in the Kuroshio axis and offshore areas of higher temperature and salinity and lower chlorophyll‐a concentration than in the inshore areas of lower temperature and salinity and higher chlorophyll‐a concentration. No marked differences in the growth rate index were found among the three areas, even though the larvae in the inshore areas showed slightly higher growth rates in 2013. Despite the broad ranges of environmental factors, no clear relationship between the growth rate index and any environmental factor was detected. The survival potential of Pacific saury larvae was considered to be at least comparable under contrasting environments across the Kuroshio axis. Such a geographical homogeneity is concluded to be attributable to compensable effects of physical and biological factors. We hypothesize that the minority under physically‐unfavorable but biologically‐favorable conditions on the inshore side of the Kuroshio axis could survive equally well as the majority under physically‐favorable but biologically‐unfavorable conditions around the Kuroshio axis and on the offshore side of the Kuroshio axis. 相似文献
139.
Relationship between coastal water properties and adult return of chum salmon (Oncorhynchus keta) along the Sanriku coast,Japan 下载免费PDF全文
Taku Wagawa Hiroshi Kuroda Shin‐Ichi Ito Shigeho Kakehi Takeshi Yamanome Takuya Kodama 《Fisheries Oceanography》2016,25(6):598-609
We investigated the relationship between adult (age‐4) return rates for chum salmon (Oncorhynchus keta) originating from the Iwate Prefecture, Japan, and coastal environmental conditions during their early ocean life in coastal residency. We analyzed distributions of water properties via intensive hydrographic observations using a conductivity–temperature–depth profiler. Both the return rates and water properties vary strongly over interannual time scales. We found that the time when the return rate decreased drastically corresponded well to the time when the frequency of warm waters in the coastal residency increased. 相似文献
140.
H. Hayama A. Ito T. Shimada Y. Kashimura 《The Journal of Horticultural Science and Biotechnology》2013,88(4):651-655
SummaryChanges in cellulose content and the accumulation of PpCesA1 mRNA, putatively encoding the catalytic subunit of cellulose synthase (CesA), were analysed in endocarp and mesocarp during endocarp hardening in peach fruit. The cellulose content of the endocarp was undetectable or very low [< 0.1 mg g–1 fresh weight (FW) of endocarp] until 48 d after full bloom (DAFB), but began to increase rapidly at 55 DAFB, when the endocarp had attained its maximum size, and reached 4.4 mg g–1 FW of endocarp at 85 DAFB. In contrast, the cellulose content of the mesocarp reached a detectable level (1.5 mg g–1 FW of mesocarp) at 34 DAFB, stayed at this level until 85 DAFB, but then was lower at 107 DAFB. PpCesA1 mRNA was detected in the endocarp throughout the hardening, but was undetectable in the mesocarp. It is suggested that PpCesA1 has a role in the rapid synthesis of cellulose in the secondary cell walls of endocarp tissue during hardening. 相似文献