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排序方式: 共有712条查询结果,搜索用时 31 毫秒
101.
Naoki Yamanaka Mio Morishita Tomomi Mori Yukie Muraki Midori Hasegawa Md. Motaher Hossain Yuichi Yamaoka Masayasu Kato 《Plant Breeding》2016,135(5):621-626
Asian soybean rust (ASR) caused by Phakopsora pachyrhizi is one of the most serious soybean (Glycine max) diseases in tropical and subtropical areas. A soybean line, PI 587855, showed a resistance phenotype against ASR pathogens in Japan and South America at high frequency; however, little is known of the genetic control of this resistance and chromosomal location of the corresponding locus. Therefore, the aim of this study was to study the inheritance of PI 587855 resistance and map the corresponding locus with SSR markers aiming to use the linked markers in marker‐assisted selection. In the segregating population, resistance to ASR appeared to be controlled by a single dominant gene. The ASR resistance locus was mapped near to the chromosomal region where the resistant loci, Rpp1 and Rpp1‐b, were previously mapped. Comparative genetic mapping and disease reaction profiles of other seven lines carrying Rpp1 or Rpp1‐b to four Brazilian ASR isolates revealed that the resistance reaction exhibited by PI 587855 was similar to that of Rpp1‐b‐carrying varieties which have useful resistance to South American ASR strains. 相似文献
102.
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104.
Field measurement of infiltration rate using an oscillating nozzle rainfall simulator in the cold, semiarid grassland of Mongolia 总被引:2,自引:0,他引:2
Recent intensive grazing in Mongolia may be significantly reducing the infiltration rate of rangeland. This study measured infiltration rates using simulated rainfall with high raindrop impact for small plots established on steppe grassland, desert grassland, and shrubland sites in Mongolia. The response of the infiltration rate to short-term livestock removal was also investigated. On the steppe grassland, a high infiltration rate was measured on an ungrazed plot with relatively dense vegetation cover; a statistically significant correlation was found between the total surface cover and final infiltration rate, indicating that surface cover by rock fragments also increased the infiltration rate to some extent. For desert grassland and shrubland, however, the surface cover condition was not a major factor controlling the final infiltration rate. After 4 years of livestock removal, the surface vegetation cover of the ungrazed plot was greater than that of the grazed plot, but no appreciable change occurred in soil penetration resistance. These results suggest that the high infiltration rate on the ungrazed plot was maintained mainly by the recovery of surface vegetation cover after the short-term livestock removal; this may indicate a potential mechanism of recovery from desertification processes for Mongolian rangeland. 相似文献
105.
Matsuo S Hayashi S Watanabe T Adachi K Miyoshi A Kato A Suzuki M 《Journal of toxicologic pathology》2009,22(4):289-292
Emphysematous cystitis is a rare disorder caused by bacterial infection and characterized by gas accumulation within the bladder wall with cyst formation. This report describes the histopathological characteristics of emphysematous cystitis found in a diabetic female beagle induced by streptozotocin and alloxan. Macroscopically, multiple cyst-like structures were observed on the cut surface of the urinary mucosa. During fixation, small specimens cut from the mucosa floated on the surface of the fixative solution. Histopathologically, multiple cysts were lined with a single layer of flattened cells found to be immunohistochemically positive for vimentin, partially positive for α-smooth muscle actin or macrophage scavenger receptor, class A, and thought to be myofibroblasts, fibroblasts or macrophages. Multinucleated giant cells were observed around the cysts, and gram-negative short bacilli were observed in the lumen of the urinary bladder. From these findings, this case was diagnosed as emphysematous cystitis. 相似文献
106.
Hiroaki Kato Shuta Asai Ayako Yamamoto-Katou Hirofumi Yoshioka Noriyuki Doke Kazuhito Kawakita 《Journal of General Plant Pathology》2008,74(1):15-23
During defense responses, plant cells produce nitric oxide (NO), which may control many physiological processes. In a previous
study, we reported that nitrate reductase (NR) is responsible in part for INF1 elicitor-induced NO production in Nicotiana benthamiana, but the possibility remains that other NO-generating system(s) contribute to NO production. In mammalian cells, NO production
is catalyzed by NO synthase (NOS). However, NOS-like enzyme(s) have never been identified in plants, and only the gene for
Arabidopsis thaliana nitric oxide-associated 1 (AtNOA1) has been identified as a putative regulator of NOS activity in plants. In this study, we cloned NbNOA1, a homolog of AtNOA1, from N. benthamiana and investigated its involvement in NO production induced by INF1. The NbNOA1 gene was silenced by a virus-induced gene-silencing (VIGS) technique. NbNOA1-silenced plants had yellowish leaves. Silencing NbNOA1 partially decreased INF1-induced NO production, while overexpressing NbNOA1 did not affect NO production. Silencing NbNOA1 suppressed INF1-induced PR1a gene expression and increased susceptibility to Colletotrichum lagenarium. These results suggest that NbNOA1 is involved in INF1-mediated NO production and is required for defense responses.
The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under accession number AB303300. 相似文献
107.
Fui Fui Ching Yoshizumi Nakagawa Keitaro Kato Osamu Murata Shigeru Miyashita 《Aquaculture Research》2012,43(2):303-310
The effects of delayed first feeding on the survival and growth of tiger grouper, Epinephelus fuscoguttatus (Forsskål 1775), larvae were examined under controlled conditions. The total length, yolk sac volume, oil globule volume, yolk sac absorption time and nutritional transition period (NTP) of the larvae fed at different first times (0, 6, 12, 18 and 24 h after the mouth opening stage; h AMO) were compared. Larval first feed intake was observed at 54 h after hatching (h AH) at 27.5 ± 0.5 °C. The yolk sac was consumed more rapidly with an increase in delayed first feeding and was significantly different among treatments (P<0.05). Larvae first fed at 0 h AMO had the longest yolk sac absorption (72 h AH) and NTP (20 h) times and had the highest survival and growth rates at the end of the experimental period (360 h AH), being significantly higher (P<0.05) than the other treatments. First mortality was observed at 69 h AH, approximately 2 h after point of no return (PNR) occurred. This study suggests that first feeding of tiger grouper larvae should commence at 0 h AMO for enhancement of larval survival and growth. 相似文献
108.
In this study, we developed a computer program for automatic prediction of watering time point by considering the environmental factors such as solar radiation, air temperature and relative humidity based on the multiple linear regression equation of leaf area and Penman Method. The experiments were carried out for a year in two watering experimental plots, one of which was controlled by pF value, and the other by the computer program. After comparing the results of the two plots, the following findings were obtained. In the computer program plot, the observed and predicted values of both leaf area and evapotranspiration indicated significant correlation at the 1% level, which suggested that the computer program had high prediction accuracy. In addition, no significant difference was observed between the two experimental plots with respects to the plant height, plant diameter, leaf area, leaf number, fresh weight, and dry weight, which demonstrated that the plants in the computer program plot had normal growth. On the other hand, although the number of flower buds and flowering shoots showed higher values at the end of certain cultivations in the computer program plot than those in pF value plot, we proposed that it was due to the effect of cumulative daily solar radiation in the greenhouse, rather than the watering. Thus, we have reached the conclusion that the computer program for automatic prediction of watering time point developed by this study has high applicability in miniature pot rose production. 相似文献
109.
Hirofumi Ido Hirofumi Nagao Hideo Kato Atsushi Miyatake Yasushi Hiramatsu 《Journal of Wood Science》2010,56(5):422-428
Tests of compression perpendicular to the grain were carried out on laminated veneer lumber (LVL) and timber. The species
tested were sugi, radiata pine, karamatsu, akamatsu, and dahurian larch; two sets of sugi specimens were tested, with the
sugi LVL products being manufactured in different plants. The strength properties of the materials for different loading directions
were compared for LVL and timber. At 5% compressive strain in the same materials, the average stress in the tangential direction
of timber was larger than that in the radial direction for all species except for radiata pine, and the average stress in
the edge-wise direction of LVL was larger than that in the flat-wise direction for all species except for radiata pine. When
the stress at 5% strain was compared in the same direction, the average stress of LVL in the edge-wise direction was larger
than that in timber in the tangential direction for all species, but there were no great differences between the average stress
of LVL in the fl at-wise direction and that of timber in the radial direction for all species except for radiation pine. There
was a close relationship between density and stress at 5% strain in LVL, especially in the edge-wise direction. For all results,
radiata pine did not follow the trend of the other species; The large annual ring width of radiata pine was considered to
have affected the results. 相似文献
110.
This study on dried shiitake mushroom [Lentinula edodes (Berk.) Pegler] focuses on the behavior of the aromatic lenthionine compound and its precursor, lentinic acid, during the
drying process. Only a small amount of lenthionine was present after the drying process, regardless of the drying temperature
or time; however, the amount increased during the rehydration process using pH 8.0 buffer. The lenthionine content after incubation
in the buffer was correlated with the lentinic acid content in the dried shiitake mushroom. The lentinic acid content increased
signifi cantly during the drying process at 40°C up to 4 h. The results show that the characteristic smell of dried shiitake
mushroom was weak after drying, and that rehydration in a mild alkaline solution was necessary to increase the smell. The
lentinic acid content of dried shiitake could serve as an indicator of the smell produced by rehydration and would be useful
in screening to select odor-rich strains. Moderate heating likely caused the increase in lentinic acid content, which might
be related to a reaction to heat. 相似文献