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排序方式: 共有389条查询结果,搜索用时 188 毫秒
131.
Kenta Ootsuka Ikuya Takahashi Katsunori Tanaka Tomio Itani Hiroaki Tabuchi Tadashi Yoshihashi Akio Tonouchi Ryuji Ishikawa 《Breeding Science》2014,64(2):115-124
Rice fragrance is an important characteristic for Southeast Asian consumers, and fragrant landraces from Japan were first recorded in the 17th century. Principal component analysis clearly showed that Japanese fragrant landraces were genetically different from non-Japanese fragrant landraces. Japanese fragrant landraces were composed of six clades, none of which carried the most common fragrance mutation, an 8-bp deletion in exon 7 of Badh2. Fragrant landraces comprised two major groups carrying different Badh2 mutations. One group carried a known SNP at exon13 and the other a SNP at the exon1-intron1 junction as splicing donor site. The latter was considered to be a potential splicing mutant group as a novel allele at Badh2. Heterozygosity (He) scores in the two fragrant groups were not significantly different from non-fragrant landraces and modern cultivars. However, lower He scores were found around the Badh2 locus in the two groups. The potential splicing mutant group showed a more extended haplotype than the E13 SNP group. A likely causal factor responsible for loss of function is a novel splicing mutation allele that may have been generated quite recently. The fragrance allele has dispersed as a result of out-crossing under local environmental conditions. 相似文献
132.
133.
In this study, to identify deep rooting accessions, we assessed the differences in root depth based on the length of the longest primary root among 586 different rice accessions: 511 Oryza sativa and 75 O. glaberrima. Malagkit Pirurutong and Binicol were identified as the two rice accessions with deepest roots through four field experiments conducted at two different locations in West Africa. For these two accessions, root depths reached 35.6 and 41.4 cm, respectively, in the first experiment at Bamako; on the other hand, their depths only reached 22.6 and 18.6 cm, respectively, in the second and third experiments at Ibadan, leading to inconsistent genotypic ranking based on root depth between the two locations. However, Malagkit Pirurutong was identified as deep rooting in both locations; in addition, it showed deep rooting in the fourth experiment in a 20-mm irrigation treatment, even when compared with the deep rooting reference Azucena. Nonetheless, this pattern was not found under a 10-mm irrigation treatment. Malagkit Pirurutong kept developing deep roots even following 60 days after sowing (DAS), whereas other shallower rooting accessions ceased deepening by 60 DAS. The longer period for deepening roots would be beneficial for terminal drought stress. 相似文献
134.
Zenta Nishio Hisayo Kojima Akiyo Hayata Norio Iriki Tadashi Tabiki Miwako Ito Hiroaki Yamauchi Timothy D. Murray 《Euphytica》2010,176(2):223-229
Wheat yellow mosaic, caused by Wheat yellow mosaic virus (WYMV), is one of the most devastating soil-borne diseases of winter wheat (Triticum aestivum L.) in Japan. Yellow-striped leaves and stunted spring growth, symptomatic of WYMV infection, result in severe yield loss.
A new putative WYMV resistance gene in the European wheat cultivar ‘Ibis’ was mapped in the cluster of microsatellite markers
including Xcfd16, Xwmc41, Xcfd168 and Xwmc181 on the long arm of chromosome 2D at the distances of 2.0 cM, 4.0 cM, 7.1 cM and 12.4 cM, respectively. WYMV-resistant cultivars
contained a common haplotype of the four markers, whereas moderately susceptible and susceptible cultivars did not. These
results should be useful in marker-assisted selection for WYMV resistance in wheat. 相似文献
135.
Discovery of mature freshwater eels in the open ocean 总被引:1,自引:0,他引:1
136.
Ryusuke Sudo Ryota Tosaka Shigeho Ijiri Shinji Adachi Hiroaki Suetake Yuzuru Suzuki Noriyuki Horie Satoru Tanaka Jun Aoyama Katsumi Tsukamoto 《Fisheries Science》2011,77(4):575-582
To improve understanding of the mechanism of early ovarian development in eels, the effects of water temperature decrease
on oocyte development, plasma levels of sex steroids [estradiol 17β (E2), testosterone (T), 11-ketotestosterone (11-KT)],
and gonadotropin β-subunit [follicle-stimulating hormone (FSHβ), luteinizing hormone (LHβ)] messenger RNA (mRNA) expression
levels were investigated. A total of 27 female Japanese eels Anguilla japonica were divided into initial, control, and test (water temperature decrease) groups. Starting on 22 September 2009, eels in
the test group were reared in a tank with gradual temperature decrease from 25°C to 15°C over 39 days, while the control group
was maintained at 25°C. The test group accumulated more oil droplets in their oocytes than did the other groups. Levels of
sex steroids, especially 11-KT, were higher in the test group. In contrast, FSHβ and LHβ mRNA expression levels were lower
in the test group. These results suggest that water temperature decrease only induced an early stage of ovarian development
that was partly affected by an 11-KT increase. For further maturation, other environmental factors related to induction of
gonadotropin increase appear to be needed. 相似文献
137.
Daiki Murayama Masayuki Tani Shinya Ikeda Jiwan P. Palta Samanthi W. Pelpolage Hiroaki Yamauchi Hiroshi Koaze 《American Journal of Potato Research》2017,94(5):524-533
The formation of cross-links between pectin molecules via Ca2+ in the potato tuber cell wall is a determinant factor on processing properties of potato and the quality of its products such as French fries. Thus, in this study, potato tubers varying significantly in their calcium concentrations were analyzed to investigate whether an increased absorption of calcium by a potato tuber led to an increase in the calcium concentration in the cell wall and how the calcium concentration in the cell wall influenced on the formation of cross-links between pectin molecules via Ca2+. Correlation analysis revealed that calcium absorbed by a potato tuber was bound to the cell wall as a water insoluble form 99 days after planting or later. Furthermore, with an increase in the calcium concentration in the cell wall, the content of chelator soluble pectin increased throughout tuber bulking and maturation stages. However, the degree of methylation was not a limiting factor in the formation of cross-links between pectin chains via Ca2+. Atomic force microscopy images of parenchyma cell walls prepared from mature potato tubers indicated an increase in the amount of calcium cross-linked pectin molecules with an increase in the calcium concentration in the cell wall. The present study demonstrated that the calcium concentration of the cell wall of potato tubers significantly affected the formation of cross-linkages between pectin molecules and, consequently, contributed to an enhanced formation of pectin-calcium networks in the cell wall. 相似文献
138.
Mizumoto N Toyota-Hanatani Y Sasai K Tani H Ekawa T Ohta H Baba E 《Veterinary microbiology》2004,99(2):113-120
Specific antibody levels of laying hens and young chickens experimentally infected with Salmonella Enteritidis and vaccinated farm flocks were evaluated by enzyme-linked immunosorbent assays (ELISAs) with two different antigens, deflagellated S. Enteritidis whole cell (DEWC) and S. Enteritidis FliC-specific 9kDa polypeptide (SEP9). Infected laying hens excreted S. Enteritidis throughout the experimental period, and the specific antibody titers in DEWC-ELISA, were significantly higher than the uninfected group. It suggests that this DEWC-specific antibody will serve as an effective indicator of S. Enteritidis infection, especially for non-vaccinated laying flocks. SEP9-specific antibodies were detected in spray-inoculated young chickens but not in oral-inoculated young chickens. Compared with greatly high SEP9-specific antibody levels of vaccinated farm flocks, no response was observed in orally infected hens. These results indicate that S. Enteritidis discontinues expressing SEP9 once it has crossed the intestinal barrier, and that SEP9-ELISA will serve as a valuable monitoring tool for the status of S. Enteritidis vaccination on a flockwide basis, independent of stable S. Enteritidis infections. 相似文献
139.
Mikami O Nakajima H Kawashima K Yoshii M Nakajima Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(7):735-738
Reproductive failure associated with porcine circovirus type 2 (PCV2) was observed in a farm, and a weak-born 8-day-old piglet was examined pathologically. Focal to locally extensive lesions, including infiltration of macrophages and lymphocytes, fibrosis and degeneration of the myocardium were observed in the heart. PCV2 antigens and nucleic acids were detected in degenerated cardiomyocytes and macrophages infiltrating the heart by immunohistochemical staining and in situ hybridization. Depletion of lymphocytes with occasional infiltration of multinucleated giant cells was seen in the lymphoid organs and PCV2 antigens were demonstrated in histiocytic cells. Crystalline arrays of viral particles were observed in infiltrated macrophages in the heart and, rarely, in cardiomyocytes by electron microscopy. Although myocarditis is a common finding in aborted or stillborn piglets in reproductive failure due to PCV2, it was also observed in the 8-day-old piglet with PCV2 association. 相似文献
140.
Change of fatty acid composition of the lumbar longissimus during the final stage of fattening in the Japanese Black cattle 下载免费PDF全文
Takeshi Honda Takafumi Ishida Ikuo Kobayashi Yusuke Oguri Yuto Mizuno Hideyuki Mannen Hiroaki Iwaisaki Shiro Kuge Kunihiko Saito Kenji Oyama 《Animal Science Journal》2016,87(4):578-583
Consideration of the shortened fattening period seems to be worthwhile for the realization of profitable beef production. In this study, change of fatty acid composition of the lumbar longissimus during the final stage of fattening was investigated in Japanese Black cattle. Each of 110 fattening animals was sampled three times: the initial two samples were taken by biopsy (25.7 months and 27.5 months on average) and the final one was from carcasses (29.9 months on average). Preliminary analysis indicated that removing muscle tissues from the constant body position of the living animals should be essential for sampling. Average monounsaturated fatty acids (MUFA) at three sampling points were 58.1%, 58.5% and 60.5%, and the differences of the third sampling with the first and second samplings were significant. Both in steers and heifers, MUFA also increased as the fattening stage proceeded, and MUFA of the heifers at all the sampling points were significantly higher than those of the steers. The increasing rate of MUFA rose from 0.21 percentage points (pp)/month at period 1 (from the first sampling to the second sampling) to 0.84 pp/month at period 2 (from the second sampling to the slaughter). 相似文献