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51.
When the influence of host species, inoculum density, temperature, leaf wetness duration, and leaf position on the incidence
of gentian brown leaf spot caused by Mycochaetophora gentianae, was examined, the fungus severely infected all seven Gentiana triflora cultivars, but failed to infect two cultivars of G. scabra and an interspecific hybrid cultivar. Inoculum density correlated closely with disease incidence, and a minimum of 102 conidia/mL was enough to cause infection. In an analysis of variance, temperature and leaf wetness duration had a significant
effect upon disease incidence, which increased with higher temperature (15–25°C) and longer duration of leaf wetness (36–72 h).
No disease developed at temperatures lower than 10°C or when leaf wetness lasted <24 h. At 48-h leaf wetness, disease incidence
was 0, 28, 77, and 85% at 10, 15, 20, and 25°C, respectively. Middle and lower leaves on the plant were more susceptible than
upper leaves. In microscopic observations of inoculated leaves, >50% of conidia germinated at temperatures >15°C after 24-h
leaf wetness. More appressoria formed at higher temperatures (15–25°C) with extended duration of leaf wetness (24–72 h). At
48-h leaf wetness, appressorium formation was 0, 8, 26, and 73% at 10, 15, 20, and 25°C, respectively. These results suggest
that temperature and leaf wetness duration were important factors for infection of gentian leaves. 相似文献
52.
53.
Eastern little tuna,Euthynnus affinis (Cantor, 1849) mature and reproduce within 1 year of rearing in land‐based tanks 下载免费PDF全文
Ryosuke Yazawa Yutaka Takeuchi Kenta Satoh Yuri Machida Kotaro Amezawa Naoki Kabeya Yukinori Shimada Goro Yoshizaki 《Aquaculture Research》2016,47(12):3800-3810
Eastern little tuna (ELT, Euthynnus affinis) is expected to see use as a novel aquaculture species due to its rapid growth and high economic value. In this study, closing of the complete life cycle of ELT in land‐based tanks was successfully carried out. Seed production of a first generation (F1) derived from wild‐caught ELT broodstock was conducted in 2010, 2011 and 2012. Survival percentages of F1 ELT at 365 days post hatching for the 2010, 2011 and 2012 year classes were 0.9%, 0.4% and 6.3% respectively. On average, F1 ELT were approximately 40 cm in total length and weighed 1500 g by the time they reached 1 year of age. Successful artificial induction of spawning was achieved in 1‐year‐old F1 ELT using a gonadotropin‐releasing hormone analogue (GnRHa). Induction of spawning was successful at the first administration of GnRHa in the 2010, 2011 and 2012 year classes. First spawning was observed at 4 or 5 days post implantation, which indicated that oogenesis and spermatogenesis progressed within 1 year of rearing in land‐based tanks. During spawning periods, the average number of fertilized eggs and the average number of hatched larvae per spawning event in the 2010, 2011 and 2012 year classes were 20,480 eggs day?1 and 177 larvae day?1, 39,423 eggs day?1 and 9347 larvae day?1, and 819,555 eggs day?1 and 674,445 larvae day?1 respectively. Therefore, it was concluded that both male and female ELT reared in land‐based tanks were capable of reproduction at 1 year of age. 相似文献
54.
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
55.
The uncertainty in pesticide residue levels (UPRL) associated with sampling size was estimated using individual acetamiprid and cypermethrin residue data from preharvested apple, broccoli, cabbage, grape, and sweet pepper samples. The relative standard deviation from the mean of each sampling size (n = 2(x), where x = 1-6) of randomly selected samples was defined as the UPRL for each sampling size. The estimated UPRLs, which were calculated on the basis of the regulatory sampling size recommended by the OECD Guidelines on Crop Field Trials (weights from 1 to 5 kg, and commodity unit numbers from 12 to 24), ranged from 2.1% for cypermethrin in sweet peppers to 14.6% for cypermethrin in cabbage samples. The percentages of commodity exceeding the maximum residue limits (MRLs) specified by the Japanese Food Sanitation Law may be predicted from the equation derived from this study, which was based on samples of various size ranges with mean residue levels below the MRL. The estimated UPRLs have confirmed that sufficient sampling weight and numbers are required for analysis and/or re-examination of subsamples to provide accurate values of pesticide residue levels for the enforcement of MRLs. The equation derived from the present study would aid the estimation of more accurate residue levels even from small sampling sizes. 相似文献
56.
Goto K Iwasawa D Kamimura Y Yasuda M Matsumura M Shimada T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(5):649-654
Probiotic strains have been reported to have the ability to control allergic and inflammatory diseases. In this study, we studied the inhibitory effect of Bacillus subtilis (natto) (BS) on atopic dermatitis. The effects of continuous oral administration of BS for 4 weeks on the development of atopic dermatitis induced by Dermatophagoides farinae body antigen (DF) in NC/Nga (NC) mice were evaluated using 4 groups of mice: group (Gp) DF, DF(+) with no administration of bacteria (n=3); Gp DF/BS, DF(+) and BS(+) (n=5); and Gp PBS, DF(-) with no administration of bacteria (n=3). The mice were gavaged with 1.2 × 10(17) CFU/head of BS 6 times a week for 4 weeks, and DF was applied twice a week for 4 weeks. Histopathological examination revealed significant differences in auricular thickness between Gp DF (664.4 μm, SD=78.0) and Gp DF/BS (278.7 μm, SD = 88.8; p<0.01). The dorsal skin of Gp DF/BS (316.7 μm, SD=187.4) was significantly thinner than that of Gp DF (503 μm, SD=116.3). These results suggest that continuous oral administration of fermented food-derived bacteria (BS) can be effective in alleviating the development of skin lesions induced by DF in NC mice. 相似文献
57.
Cloned porcine embryos can maintain developmental ability after cryopreservation at the morula stage
Nakano K Matsunari H Nakayama N Ogawa B Kurome M Takahashi M Matsumoto M Murakami H Kaji Y Nagashima H 《The Journal of reproduction and development》2011,57(2):312-316
The aim of the present study was to clarify the overall efficiency of porcine somatic cell nuclear transfer (SCNT) by incorporating cryopreservation of the cloned embryos before transfer. The SCNT embryos reconstructed with preadipocytes and in vitro-matured (IVM) oocytes were cultured to harvest morula stage embryos; they were then subjected to delipation (removal of cytoplasmic lipid droplets) and vitrification. After warming and culture, the embryos developing to blastocysts were transferred to recipients to obtain cloned piglets. From 372 reconstructed embryos, 188 (50.5%) reached the morula stage and 117 (31.5%) developed to blastocysts after vitrification. Transfer of 98 (26.3%) morphologically normal blastocysts gave rise to 6 (1.6%) piglets, including 1 stillborn. The efficiency of the cloned piglet production was comparable with that obtained using SCNT embryos without cryopreservation (2.7%, 17/635). Here, we demonstrate that porcine somatic cell cloning can be performed without a significant reduction in efficiency even when the SCNT embryos are cryopreserved before transfer. 相似文献
58.
Surveillance and characterization of Newcastle disease viruses isolated from northern pintail (Anas acuta) in Japan during 2006-09 总被引:1,自引:0,他引:1
Ruenphet S Jahangir A Shoham D Morikawa K Miyoshi Y Hanawa E Okamura M Nakamura M Takehara K 《Avian diseases》2011,55(2):230-235
A total of 38 Newcastle disease virus (NDV) isolates were obtained from 6060 fecal samples from northern pintail (Anas acuta) ducks collected in the Tohoku district in Japan during 2006-09. One isolate from each sampling location and date was selected for a total of 38 isolates, then 15 of these were characterized for their pathogenicity by mean death time of minimum lethal dose (MDT/MLD) using chicken embryos and by plaque formation on chicken embryo fibroblasts. Furthermore, nine isolates were randomly selected from these 15 isolates, and the fusion protein genes were sequenced to characterize amino acid sequences around the cleavage site. All 15 were confirmed to be nonvirulent by MDT/MLD test, and nine isolates were also confirmed as nonvirulent by the cleavage site of the fusion protein 112G/E-K/R-Q-G/E-R*L117 that was specific for nonvirulent NDVs. The characteristics of nine isolates identified by phylogenic analysis of the fusion protein gene indicated that the isolates belong to genotype I or II. In addition, we also isolated 68 avian influenza viruses and 28 other hemagglutinating viruses. Our data indicate that northern pintails are subclinically infected by, perpetuate, and distribute NDV along with different subtypes of avian influenza viruses and other hemagglutinating viruses during their migrations across vast areas over the Northern Hemisphere to Japan. 相似文献
59.
Akiyoshi H Sugii S Nahid MA Sone K Tanaka T Zheng C Yijyun L Aoki M Takenaka S Shimada T Shimizu J Kiyomiya K Ohashi F 《Veterinary immunology and immunopathology》2011,144(3-4):255-258
The reactivity of different lectins with crude chromogranin A (CgA) obtained from different animals, namely, cow, horse, dog, pig, and dolphin, was examined to identify lectin(s) that would be useful as coating reagent(s) in a sandwich enzyme-linked immunosorbent assay (ELISA). Of the different lectins studied, the Amaranthus caudatus lectin (ACA), which is specific for the Thomsen-Friedenreich (T)-antigen (Galβ1-3GalNAc), was found to react with the CgA from different animals by western blotting. Purified rabbit anti-bovine CgA antibody was also found to cross-react with the crude CgA preparations. On the basis of these findings, a sandwich ELISA was developed with ACA as the coating reagent and anti-bovine CgA antibody as the probing antibody. Using this method, concentration-dependent curves ranging from 0.003 μg/mL to 25 μg/mL and from 0.02 μg/mL to 25 μg/mL were obtained for bovine CgA and canine CgA, respectively. Similarly, concentration-dependent curves were obtained for the equine, swine, and dolphin crude CgA extracts. Thus, ACA is concluded to be a valuable reagent for CgA detection in crude extracts from different animal species, and for CgA isolation/purification. 相似文献
60.
Le Van Chinh Kazuaki Hiramatsu Masayoshi Harada Makito Mori 《Paddy and Water Environment》2008,6(4):405-414
Chiyoda basin is located in Saga Prefecture in Kyushu Island, Japan, and lies next to the tidal compartment of the Chikugo
River to which the excess water in the basin is drained away. Chiyoda basin has a total area of about 1,100 ha and is a typical
flat and low-lying paddy-cultivated area. The main environmental issue in this basin is total nitrogen (TN) and total phosphorus
(TP) load management because TN and TP, which loaded from farmlands, degrade surface water as a result of anthropogenic eutrophication.
This paper presents a mathematical model of TN and TP runoff during an irrigation period in Chiyoda basin in order to elucidate
the pollutant fluxes that accompany water transportation in paddy fields and drainage canals, and to evaluate pollutant removal
from the study area to the Chikugo River. First, the water flow and the algorithm of gate operation were simulated by a continuous
tank model and the accuracy of the model was then evaluated by comparing the simulated water levels with observed ones during
an irrigation period. The observed and simulated water levels were in good agreement, indicating that the proposed model is
applicable for drainage and water supply analyses in flat, low-lying paddy-cultivated areas. Second, the TN and TP runoff
during an irrigation period was simulated based on the TN and TP loads that were determined by observed data in paddy fields.
For TN runoff, the simulated results and observed data were in good agreement whereas for TP runoff, the simulated results
were higher than the observed data. However, if the settled TP within the paddy tank was calculated as 6%, then the simulated
results and the observed data were in good agreement. We concluded that TN runoff from paddy field to the drainage canal system
was not affected much by the sediment related process. The present study could provide farmers and managers with a useful
tool for controlling the water distribution in an irrigation period, and the TN and TP loads in the downstream area as well
as the Chikugo River. 相似文献