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61.
This study aims to investigate the impact of rice-husk power generation on agricultural uses of rice husk and its ash. We
conducted case studies at a rice-husk power plant and organic farming groups in northeast Thailand. The case study on a rice-husk
power plant showed that rice husk was useful in generating electricity without consuming fossil fuel, while husk ash, the
by-product, could be utilized as silicate supplement for farmland soils. The case study on organic farming groups indicated
that rice husk was one of the indispensable materials in conducting organic farming with locally available resources. On the
basis of these findings, an analytical study on possible husk uses in Thailand was conducted, in which three potential major
uses of rice husk were considered: i.e. (1) fuel use inside rice mills followed by husk-ash reuse, (2) fuel use at power plants
followed by husk-ash reuse, and (3) direct reuse of husk for compost production. The result indicated that there would be
conflicting demands for rice husk among those uses in the future. Therefore, there needs to be a strategy for balancing husk
uses among them. 相似文献
62.
Yoshiyuki Inagaki Kazuki Miyamoto Shiro Okuda Mahoko Noguchi Takeharu Itou Kyotaro Noguchi 《Soil Science and Plant Nutrition》2013,59(5):710-718
The stem productivity of the hinoki cypress (Chamaecyparis obtusa Endlicher) in relation to plant nitrogen status and water-use efficiency was investigated in the Okuono (OKU) and Karakawa (KRK) areas in Shikoku district, Japan, where abundant precipitation occurs. The nitrogen concentration and carbon isotopic composition (δ13C) in the leaves were used as indexes of plant nitrogen status and water-use efficiency, respectively. The leaf nitrogen concentration increased with decreasing soil carbon/nitrogen (C/N) ratio and with increasing soil pH. There was a marginally significant negative correlation between leaf δ13C and soil water content in the KRK area, but leaf δ13C in the OKU area did not correlate with the soil water condition, and increased on the upper slope. The results suggest that hinoki trees in the KRK area have higher water-use efficiency (high leaf δ13C) under lower soil water conditions. In the OKU area, meanwhile, leaf δ13C in the upper slope was higher due to adaptation to adverse conditions. When 12 plots in two areas were included, the mean height and stem increments increased with increasing leaf nitrogen concentration and with decreasing leaf δ13C. These findings suggest that nitrogen acquisition is a primary factor for stem productivity in the areas concerned but the productivity of some forests is restricted by the soil water condition or other conditions, as indicated by the high value of leaf δ13C. The measurement of nitrogen concentration and δ13C in leaves can provide us with valuable insights into the relative importance of nitrogen, water and other conditions on stem productivity in the two areas. 相似文献
63.
Hisatomi Harada Koichi Amaha Yoshiyuki Abe Youichiro Kojima Yoshihito Sunaga Tahei Kawachi 《Soil Science and Plant Nutrition》2013,59(6):782-789
AbstractRadioactive cesium (Cs) deposited after the Fukushima Daiichi Nuclear Power Station accident contaminated farmyard manure (FYM) in the wide area surrounding the plant. We conducted a field trial to determine the transfer factor of radioactive Cs to forage corn (Zea mays L.) from soil to which the contaminated FYM had been applied. The main purpose of this experiment was to examine the behavior of the radioactive Cs from contaminated FYM that was incorporated in agricultural fields. Application of FYM containing 3900 Bq kg?1 dry matter (DM) of cesium-137 (137Cs) at a rate of 4.3 kg m?2 increased the 137Cs concentration in the soil by 64 Bq kg?1 dry soil, and in the forage corn by 9.2 Bq kg?1 DM. Therefore, we calculated the transfer factor to corn plants from the soil after application of contaminated FYM to be 0.14. This value is lower than that observed for soil to which uncontaminated FYM had been applied as a control, and it is within the range of reported soil-to-plant transfer factors of 0.003–0.49 listed in the recent parameter handbook by International Atomic Energy Agency. The increase in the radioactive Cs concentration in the corn plants, expressed as the sum of 137Cs and cesium-134 (134Cs), was only 3% of the 2012 provisional tolerance level for cattle roughage in Japan. Even though the application of contaminated FYM did not cause a large change in the radioactive Cs concentration in the corn plants in this trial, such application should be carefully controlled because it increased radioactive Cs concentrations in both soil and forage corn. 相似文献
64.
Yoshiyuki Yanase Masahiro Miura Yoshihisa Fujii Shogo Okumura Tsuyoshi Yoshimura 《Journal of Wood Science》2013,59(3):243-248
A gas detection apparatus equipped with a semiconductor gas sensor was employed for qualitative and quantitative measurement of hydrogen and methane emitted by termites. A gas sample of 2.5 ml was injected into the semiconductor gas sensor through the gas detection apparatus, and the maximum voltage of the sensor was converted into gas concentration. The gas samples were collected from three distinct experiments: (1) five combinations of workers and soldiers of Coptotermes formosanus with and without a wood specimen; (2) C. formosanus under six temperature conditions; and (3) four different termite species, C. formosanus, Reticulitermes speratus, Incisitermes minor, and Zootermopsis nevadensis. The hydrogen and methane concentrations increased with an increase in the number of termites. Concentrations were higher in samples with a wood specimen than without it. Both hydrogen and methane concentrations were the highest for the samples at 35 °C and were lowest at 15 and 5 °C. The concentrations were very low at 45 °C because all the termites had died in a few hours. The concentrations of hydrogen and methane were highest for Z. nevadensis, the dampwood termite, among the four species, and no methane was detected for I. minor, the drywood termite, at 28 °C and 75 % RH. 相似文献
65.
Yoshiyuki Takeda 《茶叶》2013,(4):201-204
Tea breeding in Japan started around 116 years ago,and to date,more than 110 cultivars have been developed and released.Seedling plants were uprooted and rapidly replaced with new clonal cultivars after 1970.At present,more than 95% of the tea gardens in Japan grow improved clonal cultivars.Although the cultivation of the "Yabukita" variety had expanded and contributed to approximately 76% of the tea grown,this excessive plantation resulted in some serious problems in the cultivation and management of the tea industry after 1990.Therefore,after 2000,new programs have been initiated to breed superior varieties through the use of various genetic resources and DNA markers. 相似文献
66.
Seiji KATAGIRI Masaharu MORIYOSHI Yoshiyuki TAKAHASHI 《The Journal of reproduction and development》2013,59(6):575-579
A high incidence (about 70%) of alteration in endometrial epidermal growth factor
(EGF) profile, i.e., loss of 2 peaks on days 2–4 and 13–14, has been linked to a
reduced fertility in multiparous repeat breeder Holstein cows. However, the EGF
profile in Holstein heifers and other breeds (types) of cattle has not been
investigated. In study 1, EGF concentrations were determined using endometrial
tissues obtained by biopsy on days 3, 7 and 14 from 84 fertile Holstein heifers to
obtain a normal range and 53 repeat breeder Holstein heifers to estimate incidence of
alterations in the EGF profile. In repeat breeder heifers, EGF concentrations were
similar to fertile controls on 3 days and five animals (9.4%) had an altered EGF
profile with EGF concentrations below the normal range on days 3 and 14. In study 2,
EGF concentrations on day 3 were repeatedly examined from the nulliparous period to
the third postpartum period in 28 Holstein (dairy) and 47 Japanese Black (beef)
cattle. The effect of parity on EGF concentrations on day 3 was different between
Holstein and Japanese Black cattle. In Japanese Black cows, the EGF concentrations
were consistently high throughout the study period, while in Holstein cows, the EGF
concentrations decreased after the second calving. In conclusion, unlike multiparous
repeat breeder Holstein cows, an altered EGF profile may not be a major cause of
repeat breeding in Holstein heifers, and the peak EGF concentrations around day 3 may
decrease even in fertile populations of multiparous dairy cows, but not in beef
cows. 相似文献
67.
Francis Wachira Junichi Tanaka Yoshiyuki Takeda 《The Journal of Horticultural Science and Biotechnology》2013,88(5):557-563
SummaryGenetic variation and resulting variable groupings in tea (Camellia sinensis) and its wild Camelia relatives were assessed using Random Amplified Polymorphic DNA (RAPD) and Amplified Fragment Length Polymorphic (AFLP) markers. Numerous polymorphic bands were generated, of which 266 unambiguous ones were scored. The highest level of polymorphism as determined by the expected heterozygosity (Hav) was detected with AFLPs. Three major groups were recognized in the germplasm based on the parsimony method of cluster analysis. Two of the groups corresponded to varieties assamica and sinensis while the third group consisted of a heterogeneous mix of tea cultivars and related wild species. The Taiwan yamacha, unique tea cultivars grown predominantly in the highlands of Taiwan for the production of pan fired semi-fermented (Oolong and Pouchong) tea clustered in this group. Analysis of phenotypic diversity based on the generated RAPD and AFLP profiles revealed that population diversity (H), decreased in the order; Wild Camellia >India > China > Kenya > Sri-lanka > Vietnam > Japan > Taiwan. Analysis of molecular variance (AMOVA) revealed that most variation resided among individuals within populations (72%). Calculation of genetic distances and nested AMOVA further revealed a significant degree of structuring among the populations based on the country of origin. 相似文献
68.
Fuyumi Takahashi Hideki Ogiso Masashi Fujinaga Yoshiyuki Ishiyama Yasuhiro Inoue Takashi Shirakawa Yuichi Takikawa 《Journal of General Plant Pathology》2013,79(4):260-269
In October 2010, a bacterial disease produced flecks and spots on leaves of Chinese cabbage, cabbage and Japanese radish in Nagano Prefecture, Japan. The symptoms started on the abaxial surface of leaves as angular, water-soaked flecks of 1–2 mm in diameter with a yellow halo of 3–4 mm width. These flecks then became visible on both leaf surfaces, enlarged and coalesced into large blight lesions. The symptoms were similar to bacterial leaf spot caused by Pseudomonas syringae pv. maculicola. The bacterium isolated from leaf lesions formed a white colony and produced polysaccharides on YP agar. The isolates were identified as P. syringae group by LOPAT tests and the 16S rDNA sequence. Moreover, the results of pathogenicity on cruciferous plants, bacteriological characteristics, rep-PCR and the sequences of rpoD and gyrB showed that the isolates should be identified as P. cannabina pv. alisalensis (recently transferred from P. syringae pv. alisalensis). This is the first report of P. cannabina pv. alisalensis isolated from diseased crucifers in Japan. 相似文献
69.
70.
The growth and survival of three strawberry pathogens, Fusarium oxysporum f. sp. fragariae (FOF), Phytophthora cactorum, and Verticillium dahliae, were examined in anaerobic (anoxic) conditions at several temperatures (10–40 °C). The growth and survival of these fungi were suppressed by anaerobic conditions in comparison with those in cultured aerobically. Under anaerobic conditions at 22.5 °C, tested isolates of FOF and P. cactorum grew slightly, but V. dahliae did not grow. The three fungi survive for markedly shorter time in the anaerobic conditions compared with the aerobic conditions at all tested temperatures except 40 °C for FOF and P. cactorum. Moreover, survival periods shortened as the cultivation temperature increased. These results demonstrate that anaerobic conditions contribute to eradicating these pathogens during flooding or reductive soil disinfestation. 相似文献