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31.
Masako Seki Makiko Chono Tsutomu Nishimura Mikako Sato Yasuhiro Yoshimura Hitoshi Matsunaka Masaya Fujita Shunsuke Oda Katashi Kubo Chikako Kiribuchi-Otobe Hisayo Kojima Hidetaka Nishida Kenji Kato 《Breeding Science》2013,63(3):309-316
The Ppd-A1 genotype of 240 Japanese wheat cultivars and 40 foreign cultivars was determined using a PCR-based method. Among Japanese cultivars, only 12 cultivars, all of which were Hokkaido winter wheat, carried the Ppd-A1a allele, while this allele was not found in Hokkaido spring wheat cultivars or Tohoku-Kyushu cultivars. Cultivars with a photoperiod-insensitive allele headed 6.9–9.8 days earlier in Kanto and 2.5 days earlier in Hokkaido than photoperiod-sensitive cultivars. The lower effect of photoperiod-insensitive alleles observed in Hokkaido could be due to the longer day-length at the spike formation stage compared with that in Kanto. Pedigree analysis showed that ‘Purple Straw’ and ‘Tohoku 118’ were donors of Ppd-A1a and Ppd-D1a in Hokkaido wheat cultivars, respectively. Wheat cultivars recently developed in Hokkaido carry photoperiod-insensitive alleles at a high frequency. For efficient utilization of Ppd-1 alleles in the Hokkaido wheat-breeding program, the effect of Ppd-1 on growth pattern and grain yield should be investigated. Ppd-A1a may be useful as a unique gene source for fine tuning the heading time in the Tohoku-Kyushu region since the effect of Ppd-A1a on photoperiod insensitivity appears to differ from the effect of Ppd-B1a and Ppd-D1a. 相似文献
32.
Blackening in heartwood was investigated in relation to the metal contents and the moisture content in xylem of about 50-year-old seedling sugi (Cryptomeria japonica D. Don) planted in a steeply sloped stand in Okutama district (Itsukaichi Tokyo), where blackened heartwood is frequently found. The potassium, calcium, iron, and manganese contents were examined in the variously blackened heartwood and normal heartwood by an atomic absorption method. It was recognized that potassium increased relative to the degree of the blackening of heartwood, resulting in a significant correlation between them. This finding implies that an increase in potassium has an important role in the blackening of heartwood. Moisture content has a tendency to increase in the blackened heartwood, so it seems that the large accumulation of potassium is associated with the high moisture content in heartwood.This work was presented at the 43rd Annual Meeting of the Japan Wood Research Society at Morioka, August 1993 相似文献
33.
M Saito Y Shibata M Kubo I Sakakibara A Yamada H Itagaki 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(3):307-309
Sarcocystis hominis was first isolated from slaughtered cattle raised in Japan. Cysts were 1,220-4,460 x 80-384 microns in size and their wall was 3 to 6 microns thick and appeared radially striated in the histopathological sections because of the presence of palisade-like villar protrusions on the surface. The protrusions were 3.1-4.3 x 0.7-1.1 microns in size and had many microtubules in the core. Two cynomolgus monkeys, Macaca fascicularis, fed with the Sarcocystis cysts began to pass sporocysts, which measured a size of 14.3-15 x 9.5-10 microns, in the feces 10 days after ingestion. 相似文献
34.
Daisuke Kamikawa Katsushi Kuroda Mariko Inoue Satoshi Kubo Takahiro Yoshida 《Journal of Wood Science》2009,55(6):453-457
In this study, the combustion properties of wood pellets were evaluated using a cone calorimeter, which is usually used to
verify the fireproof performance of architectural materials. In contrast to the conventional methods including combustion
calorimetry and thermogravimetric analysis, a cone calorimeter can estimate various combustion parameters, e.g., changes of
heat release rate (HRR), weight decrease during burning process, ignition time, and flame-out and burn-out time as well as
combustion heat, in a single experimental run with no pretreatment for sample size reduction. The following results were obtained
by the combustion test of Japanese cedar (Cryptomeria japonica) and larch (Larix kaempferi) wood pellets having various volume densities. Ignition time of wood pellet became slower with increasing volume density
of the pellets. However, burn-out time was not clearly correlated to volume density. The heat release values measured by cone
calorimeter could be comparable to those from the conventional combustion calorimeters, and flaming heat values of the bark
pellets were always lower in comparison with pellets made of xylem, although total heat release was almost the same. 相似文献
35.
一种农杆菌介导稻瘟病菌的遗传转化 总被引:3,自引:0,他引:3
以农杆菌C58C1及携带潮霉素抗性的质粒pBIG2RHPH2为介导,以广泛不致病的野生型稻瘟病菌CY2为出发菌株,开展稻瘟病菌T-DNA插入转化条件的研究。农杆菌OD600为0.1条件下,乙酰丁香酮(AS)200μmol/L,用IM培养基(pH5.2)共培养。结果表明,在潮霉素、头孢噻肟钠和壮观霉素为200μg/mL,2mm滤纸条筛选培养,转化效率最高,平均可获得329.0个转化子/1×104个孢子。通过对转化子的继代稳定性和PCR检测,证明转化子均获得了T-DNA插入片段,且能稳定遗传。采用接种法,在不同遗传背景的44个抗稻瘟病的水稻近等基因系接种8000个转化子,获得20个致病突变体。 相似文献
36.
We demonstrate a method for evaluating the appropriate number of samples required to estimate plant species richness in different
forest types within a forested landscape. In each of 36 plots (0.1 ha each) from 5 forest types (deciduous broad-leaved secondary
forest and 4 categories of coniferous plantation classified according to stand age) in central Japan, 40 quadrats of 1 × 1 m
were set in a regular pattern; the total number of quadrats in each forest type ranged from 200 to 400. In each plot, the
number of observed species in 40 quadrats ranged from 60 to 80% of the number of species estimated by the rarefaction method
for each forest type. Sampling 30 quadrats detected approximately 90% of the observed species in each plot that were detected
using 40 quadrats. In specific functional groups (i.e., tall trees and weed species), the ratios of both tall trees and weed
species to all species were at equilibrium for 30 or more quadrats. For fewer than 30 quadrats these ratios were highly variable.
No significant differences were found among forest types in the ratio of the observed number of species in each plot to the
estimated number of species calculated using the rarefaction method, and in sampling efficiency estimated by use of non-parametric
estimators. We concluded that the number of samples does not need to be changed according to forest type or plantation stand
age in the studied landscape, and that the method used to evaluate the number of samples could be useful. 相似文献
37.
Masako Kubo Koji Shimano Hitoshi Sakio Yuji Isagi Keiichi Ohno 《Journal of Forest Research》2010,15(5):337-340
Cercidiphyllum japonicum and C. magnificum are deciduous tree species that produce large numbers of sprouts. They are found mainly in riparian and/or disturbed areas.
C. japonicum is distributed in the montane zone in Japan, whereas C. magnificum is distributed mostly in the subalpine zone of central Japan. However, the two species sometimes coexist, e.g., on the talus
slope at the valley head of the Chichibu Mountains. We investigated differences in sprouting traits in these two species by
comparing class distributions of sprout diameter at breast height (DBH) and heights of individuals on the talus slope. Sprout
DBH and individual height were smaller in C. magnificum as compared to C. japonicum. Moreover, the analysis of the DBH-class distribution of each species indicated that C. magnificum had numerous small sprouts and experienced high mortality, whereas C. japonicum had fewer small sprouts and low mortality. It is likely that the sprouting traits of C. magnificum make it more adapted to severe conditions in the subalpine zone than those of C. japonicum. 相似文献
38.
Tada Y Yano N Takahashi H Yuzawa K Ando H Kubo Y Nagasawa A Chin K Kawamata Y Sakai R Ohashi N Ogata A Nakae D 《Journal of toxicologic pathology》2010,23(1):39-47
A subchronic feeding study of l-serine (l-Ser) was conducted with groups of 10 male and 10 female Fischer 344 rats fed a powder diet containing 0, 0.06, 0.5, 1.5 or 5.0% concentrations of l-Ser for 90 days. There were no toxicologically significant, treatment-related changes with regards to body weight, food intake, water intake or urinalysis data. In several of the hematology, serum biochemistry and organ weight parameters, significant changes were observed between some of the treated groups and the controls. All these changes, however, were subtle and lacked any corresponding pathological findings. In addition, the increased or decreased values remained within the range of the historical control values. In fact, histopathological assessment revealed only sporadic and/or spontaneous lesions. In conclusion, the no-observed-adverse-effect-level (NOAEL) for l-Ser was, therefore, determined to be at least a dietary dose of 5.0% (2765.0 mg/kg body weight/day for males and 2905.1 mg/kg body weight/day for females) under the present experimental conditions. 相似文献
39.
Kubo K Entani T Takara A Wang N Fields AM Hua Z Toyoda M Kawashima S Ando T Isogai A Kao TH Takayama S 《Science (New York, N.Y.)》2010,330(6005):796-799
Self-incompatibility in flowering plants prevents inbreeding and promotes outcrossing to generate genetic diversity. In Solanaceae, a multiallelic gene, S-locus F-box (SLF), was previously shown to encode the pollen determinant in self-incompatibility. It was postulated that an SLF allelic product specifically detoxifies its non-self S-ribonucleases (S-RNases), allelic products of the pistil determinant, inside pollen tubes via the ubiquitin-26S-proteasome system, thereby allowing compatible pollinations. However, it remained puzzling how SLF, with much lower allelic sequence diversity than S-RNase, might have the capacity to recognize a large repertoire of non-self S-RNases. We used in vivo functional assays and protein interaction assays to show that in Petunia, at least three types of divergent SLF proteins function as the pollen determinant, each recognizing a subset of non-self S-RNases. Our findings reveal a collaborative non-self recognition system in plants. 相似文献
40.
This paper introduces an irrigation system developed in the floodplain of a lake and studies the water management technique
of the irrigation system by estimating the total water balance of the whole system. The system is characterized by a reservoir
combined with a dike system in the floodplain of the Tonle Sap Great Lake and an irrigation system. Two main models are used
for calculating the total water balance. The first model is the water balance of the reservoir. The inputs to the model are
water level of the reservoir, precipitation, lake evaporation, infiltration, and area–volume curve of the reservoir. The outputs
are inflow and outflow of the reservoir. The supply from the reservoir to paddy fields is computed from the outflow. The second
model is the water balance of paddy fields, based on which the water requirement in paddy fields is derived. The reference
evapotranspiration needed to calculate the water requirement is simulated for monthly time series using the FAO Penman–Monteith
model. Since there is no drainage network in the irrigation system, surface drainage and runoff are not included in the calculation
of the water balance, and seepage is considered negligible in the flat floodplain area. The evapotranspiration, rice variety,
soil type and irrigated area are used to simulate water consumption in paddy fields. Finally, the two models are connected
to produce the total water balance from the reservoir to paddy fields. The total outflow from the reservoir is estimated and
the total water consumption for dry season cultivation is also determined. Finally, the efficiency of the whole system is
examined. 相似文献