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41.
Shuirong Tang Weiguo Cheng Ronggui Hu Miyuki Nakajima Julien Guigue Samuel Munyaka Kimani Satoru Sato Keitaro Tawaraya Xingkai Xu 《Journal of Soils and Sediments》2017,17(7):1843-1851
Purpose
Understanding the effects of temperature and moisture on soil organic carbon (SOC) dynamics is crucial to predict the cycling of C in terrestrial ecosystems under a changing climate. For single rice cropping system, there are two contrasting phases of SOC decomposition in rice paddy soils: mineralization under aerobic conditions during the off-rice season and fermentation under anaerobic conditions during the growth season. This study aimed to investigate the effects of soil temperature and moisture on SOC decomposition under the aerobic and subsequently anaerobic conditions.Materials and methods
Two Japanese paddy soils (Andisol and Inceptisol) were firstly incubated under four temperatures (±5, 5, 15, and 25°C) and two moisture levels (60 and 100% water-filled pore space (WFPS)) under aerobic conditions for 24 weeks. Then, these samples were incubated for 4 weeks at 30°C and under anaerobic conditions. Carbon dioxide (CO2) and methane (CH4) productions were measured during the two incubation stages to monitor the SOC decomposition dynamics. The temperature sensitivity of SOC was estimated by calculation of the Q10 parameter.Results and discussion
The total CO2 production after the 24-week aerobic incubation was significantly higher in both soils for increasing soil temperature and moisture (P < 0.01). During the subsequent anaerobic incubation, total decomposed C (sum of CO2 and CH4 productions) was significantly lower in samples that had been aerobically incubated at higher temperatures (15 and 25°C). Moreover, CH4 production was extremely low in all soil samples. Total decomposed C after the two incubation stages ranged from 256.8 to 1146.1 mg C kg?1 in the Andisol and from 301.3 to 668.8 mg C kg?1 in the Inceptisol. However, the ratios of total decomposed C to SOC ranged from 0.29 to 1.29% in the Andisol and from 2.21 to 4.91% in the Inceptisol.Conclusions
Both aerobic and anaerobic decompositions of SOC in two paddy soils were significantly affected by soil temperature and moisture. Maintaining optimal soil temperature and medium moisture during the off-rice season might be an appropriate agricultural management to mitigate CH4 emission in the following rice growth season. Although it is high in SOC content, Andisol has less biodegradable components compared to Inceptisol and this could be a probable reason for the distinct difference in temperature sensitivity of SOC decomposition between two paddy soils.42.
Kenji Nashima Shingo Terakami Sogo Nishio Miyuki Kunihisa Chikako Nishitani Toshihiro Saito Toshiya Yamamoto 《Breeding Science》2015,65(3):208-215
Gametophytic self-incompatibility in Japanese pear (Pyrus pyrifolia Nakai) is controlled by the single, multi-allelic S-locus. Information about the S-genotypes is important for breeding and the selection of pollen donors for fruit production. Rapid and reliable S-genotype identification system is necessary for efficient breeding of new cultivars in Japanese pear. We designed S allele-specific PCR primer pairs for ten previously reported S-RNase alleles (S1–S9 and Sk) as simple and reliable method. Specific nucleotide sequences were chosen to design the primers to amplify fragments of only the corresponding S alleles. The developed primer pairs were evaluated by using homozygous S-genotypes (S1/S1–S9/S9 and S4sm/S4sm) and 14 major Japanese pear cultivars, and found that S allele-specific primer pairs can identify S-genotypes effectively. The S allele-specific primer pairs developed in this study will be useful for efficient S-genotyping and for marker-assisted selection in Japanese pear breeding programs. 相似文献
43.
Mizoguchi T Itou K Sakurai M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(1):95-97
The hemagglutinating activity and serological properties of three strains of rabbit hemorrhagic disease virus, Chinese, Korean and Shizuoka, which was first isolated in Japan, were examined by hemagglutination (HA) and cross hemagglutination inhibition (HI) test with human erythrocytes. Similar results were observed between the Chinese and Korean strains, both of which gave positive HA at 4 degrees C with O, A, B and AB, and at 22 degrees C with B and AB blood groups. In the Shizuoka strain, positive HA was observed at 4 degrees C with O, A, B and AB, at 22 degrees C with A, B And AB, and at 37 degrees C with B blood group. In experimentally infected rabbits, HI antibody in these animals showed a titer of 16,384 or 32,768 at 4 weeks after inoculation. No serological difference was observed in three strains by cross HI test. 相似文献
44.
Masayuki FUJIWARA Miyuki SAKAGUCHI Bo-Song RYAN Satoshi T OHKI Takeshi OSAKI 《Journal of General Plant Pathology》2001,67(2):159-163
Local lesion formation on cowpea leaves was more than 50% inhibited by treatment with a 23 kDa RNase-like glycoprotein from
Cucumis figarei, figaren, from 24 hr before to 1 hr after inoculation with Cucumber mosaic virus (CMV). CMV accumulation detected by ELISA in tobacco leaves treated with figaren 6 or 0 hr before inoculation with CMV was
suppressed. When upper leaves of tobacco plants were treated with figaren and inoculated 10 min later with CMV, mosaic symptoms
were delayed for 5–7 days on most of the tobacco plants, and some plants remained asymptomatic. From fluorescence in situ hybridization, infection sites were present in figaren-treated cowpea or melon leaves after inoculation with CMV, though the
sites were reduced in number and size compared with those in water-treated control leaves. The amount of CMV RNAs and CMV
antigen in melon protoplasts inoculated with CMV and subsequently incubated with figaren similarly increased with time as
did that in the control. ELISA and local lesion assays indicated that CMV infection on the upper surfaces of the leaves of
tobacco, melon, cowpea and C. amaranticolor whose lower surfaces had been treated with figaren 5–10 min before CMV inoculation was almost completely inhibited. Figaren
did not inhibit CMV infection on the opposite untreated leaf halves of melon, cowpea and C. amaranticolor, whereas it almost completely inhibited CMV infection on the untreated halves of leaves of tobacco. CMV infection was not
inhibited in the untreated upper or lower leaves of the four plants. These data suggest that figaren does not completely prevent
CMV invasion but does inhibit the initial infection processes. It may also induce localized acquired resistance in host plants.
Received 10 October 2000/ Accepted in revised form 6 February 2001 相似文献
45.
The distribution of starch granules in ungerminated seeds of Zostera marina was examined by electron microscopy and histochemistry. Quantitative changes during germination in starch and sugars [glucose/maltosaccharides
(MS), sucrose, and fructose] were examined in the seeds using biochemical methods. At natural seawater salinity (30.2 psu),
the number of starch granules and the amount of starch markedly decreased, resulting in no increase in the sugar content in
the embryos during the early germination stage. A substantial increase in sugars in the shoots occurred after the development
of true leaves, probably due to photosynthetic activity in the green true leaves. At natural seawater salinity, the amount
of starch did not significantly change during the initial 14 days of germination. In contrast, at lower salinities, starch
levels decreased significantly from day 0 to day 6, resulting in higher levels of glucose/MS and fructose in the basal hypocotyls.
These results suggest that compared with the salinity of natural seawater, lower salinity may interfere with starch catabolism
in seeds, thereby causing the seed coat to break open earlier. 相似文献
46.
Marine teleosts are known to produce white feces, which is often referred to as Ca precipitates. Ca precipitates have been
suggested to be a product of osmoregulation. In the present study, we examined the physicochemical nature of Ca precipitates,
and possible involvement of Ca precipitate formation in hyposmoregulatory processes in seawater-acclimated Japanese eel. Whereas
Ca precipitates were not produced in eel acclimated to freshwater, Ca precipitates were seen in eel acclimated to seawater
in a salinity-dependent manner. According to X-ray diffraction analysis, Ca precipitates were a mixture of carbonate minerals:
Mg-calcite and its amorphia. Quantitative analysis showed that the molar ratio between Ca and Mg was approximately 7:2. Ca
precipitate formation was reduced in eel exposed to low-Ca2+ or low-Mg2+ seawater, indicating that Ca and Mg in Ca precipitates were derived from seawater. 相似文献
47.
Mahiko Abe Keigo Yokota Masaki Goto Akira Kurashima Miyuki Maegawa 《Fisheries Science》2008,74(2):299-307
ABSTRACT: This study was designed to identify a sustainable Zostera marina population based on the relationships between the distributional patterns of shoots and light conditions in the population. Population structures and light conditions on 22 April 2003 (season of reducing shoot density), 27 September 2003 (season of the annual minimum density and biomass) and 9 April 2004 (season of the annual maximum density and biomass) were examined. On 22 April 2003, the frequency distribution in shoot length was almost even. The spatial pattern is characterized by small clumps within 2–5 cm radius. On 27 September 2003, the lengths of all shoots were less than 40 cm, and the distributional patterns were similar to 22 April. On 9 April 2004, the spatial pattern is characterized by larger clumps within 25 cm radius. The reproductive shoots had a regular distribution. The relative light intensities on the population floor of the sea surface on 27 September and 9 April were 53.3 and 10.2%, respectively. The light intensity on 9 April 2004 was not sufficient for growth. The results suggest that the competition for harvesting solar radiation is caused by the shoot length and the spatial pattern among shoots in the population. 相似文献
48.
Sasaki N Yamada M Morita Y Furuoka H Itoh M Satoh M Yamada H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(12):1367-1369
We report a case of EMND in a heavy horse that was bred and trained in Hokkaido, Japan. Clinical symptoms included severe ataxia of all four limbs, tilted head, lethargy, and flaccid lips. Numerous axonal degenerations and swellings were observed in nuclei, mostly in the cerebellar dentate nucleus and the nucleus of the hypoglossal nerve, and in the ventral horn of the spinal cord. In the ventral horn of the spinal cord, neuronal degeneration, swelling, and/or necrosis were observed sporadically. The case was diagnosed as EMND from the clinical symptoms and pathological findings. 相似文献
49.
50.
Jung Jung-Mo Matsushita Yoshiki Hirose Miyuki Sakai Takeshi Kawauchi Yohei Yoda Mari 《Fisheries Science》2021,87(3):263-270
Fisheries Science - We compared the shapes and catches of two trawl nets having differing headrope and groundrope configurations based on paired tow data collected by two research vessels (Yoko... 相似文献