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91.
Takahiro Tezuka Keisuke Waki Kazutoshi Yashiro Maki Kuzuya Tomoko Ishikawa Yasumasa Takatsu Makoto Miyagi 《Euphytica》2009,168(2):177-188
Resistance to Fusarium oxysporum f.sp. melonis race 2 is conferred by a single dominant gene, Fom-1 in melon. Here, we identified DNA markers tightly linked to Fom-1 that could be used for marker assisted selection in breeding programs. First, we developed 125 F2 plants derived from the cross between melon lines P11 (fom-1fom-1) and MR-1 (Fom-1Fom-1). Using the F2 population, we constructed a linkage map including 14 SSR markers which had not been mapped previously. Fom-1 was confirmed to be allocated to linkage group 7. Then, we identified four AFLP markers using bulked segregant analysis.
The AFLP marker TAG/GCC-470 was completely linked to Fom-1 and other three markers were mapped near Fom-1. TAG/GCC-470 and TCG/GGT-400 were respectively converted to STS and CAPS markers. Usefulness of DNA markers was confirmed
in the analysis with several melon cultivars and lines. 相似文献
92.
M. Nazrul Islam Keisuke Ando Hidefumi Yamauchi Yoshinori Kobayashi Nobuaki Hattori 《Wood Science and Technology》2008,42(4):343-350
In this study, the ability of passive impregnation of Douglas fir (Pseudotsuga menziesii Franco) lumber was compared with a conventional full cell method. With an incising density of 10,000 holes/m2 carried out by CO2 laser, square Douglas fir lumber was treated by both passive impregnation and full cell method for 6 h and 50 min. Different
incising densities were also used in passive impregnation to examine the optimum incising density. It was observed that there
was no significant difference between these two methods regarding absorption of liquid, moisture content after dipping and
penetrated area both at cross and longitudinal sections. However, the value was higher in case of full cell method. Regarding
different incising densities, absorption and penetration of liquid was similar for 10,000 and 7,500 holes/m2 but it was low for 5,000 holes/m2. Therefore, it can be concluded that an incising density of 7,500 holes/m2 is the optimum for passive impregnation. The absorption of liquid and its distribution in wood indicates that this non-pressure
passive impregnation method can be a good preservation method for impermeable lumber and can be an alternative to full cell
method. 相似文献
93.
To investigate the influence of heating and drying history on the microstructure of dry wood, in addition to the dynamic viscoelastic
properties, CO2 adsorption onto dry wood at ice.water temperature (273 K) was measured, and the micropore size distribution was obtained
using the Horvath-Kawazoe (HK) method. Micropores smaller than 0.6 nm exist in the microstructures of dry wood, and they decreased
with elevating out-gassing temperature and increased again after rewetting and drying. Dry wood subjected to higher temperatures
showed larger dynamic elastic modulus (E′) and smaller loss modulus (E″). This is interpreted as the result of the modification at higher temperature of the instability caused by drying. Drying
history influenced the number of micropores smaller than 0.6 nm in dry wood not subjected to high temperature, although the
difference in the number of micropores resulting from the drying history decreased with increasing out-gassing temperature.
A larger number of micropores smaller than 0.6 nm exist in the microstructure of dry wood in more unstable states, corresponding
to smaller E′ and larger E″ than in the stable state. Consequently, unstable states are considered to result from the existence of temporary micropores
in the microstructures of dry wood, probably in lignin.
Part of this report was presented at the 55th Annual Meeting of the Japan Wood Research Society, Kyoto, March 2005, and at
the 56th Annual Meeting of the Japan Wood Research Society, Akita, August 2006 相似文献
94.
Keisuke Kojiro Yuzo Furuta Makoto Ohkoshi Yutaka Ishimaru Misao Yokoyama Junji Sugiyama Shuichi Kawai Takumi Mitsutani Hiromasa Ozaki Minoru Sakamoto Mineo Imamura 《Journal of Wood Science》2008,54(6):515-519
To investigate the changes in microstructures of wood with elapsed time in the environment, CO2 adsorption onto dry wood was measured at ice-water temperature (273 K) for samples aged from 0.1 years to over 1000 years.
The micropore size distribution was obtained using the Horvath-Kawazoe method. Micropores smaller than 0.6 nm in wood decreased
in number with elapsed time in the environment, and a negative correlation was found between cumulative pore volume for pores
smaller than 0.6 nm and elapsed time in the environment. Cumulative pore volume in the 1000-year sample was almost half of
that in the 0.1- year sample. Micropores smaller than 0.6 nm in wood with a few decades or more of elapsed time increased
in number after rewetting and drying. Consequently, microstructures of wood with longer time elapsed in the environment were
considered to be more stable, because of longer-term thermal motion and possibly more repeated moisture adsorption and desorption
and/or temperature variation in the environment. 相似文献
95.
Influence of histories on dynamic viscoelastic properties and dimensions of water-swollen wood 总被引:1,自引:1,他引:0
The influences of heating history, cooling method, and cooling set on microstructures and the mechanical properties of water-swollen
wood were studied by measuring viscoelastic properties and dimensional changes while elevating temperatures between 20°C and
90°C. Both the viscoelastic properties and dimensional changes of waterswollen wood in the first heating process were quite
different from those in the other heating processes. The results revealed that the molecular state of green wood around room
temperature was stabilized and could not return to this state if drying or heating was carried out. Cooling methods greatly
affected the viscoelastic properties, while they hardly affected dimensional changes when the temperature was elevated. Localized
stress in the microstructures of water-swollen wood produced by quenching affected the mechanical properties in the heating
process, while external stress less than the proportional limit caused by a cooling set had no effect. This revealed that
much greater localized stress linked to the instability of waterswollen wood than the external stress in relation to the cooling
set occurred.
Part of this report was presented at the 53rd Annual Meeting of the Japan Wood Research Society, Fukuoka, March 2003 相似文献
96.
We investigated the temporal changes in creep and stress relaxation behavior in both microscopic crystalline cellulose and macroscopic strain of wood specimen using Japanese cypress (Chamaecyparis obtusa Endl.) to understand the viscoelastic properties of wood cell walls. Specimens 600 µm in thickness were observed by the X-ray diffraction and submitted to tensile load. The crystal lattice strain of (004) plane and macroscopic strain of specimen were continuously detected during creep and stress relaxation tests. It was found that the creep compliance based on macroscopic strain showed a gradual increase after instantaneous deformation due to loading and then the parts of creep deformation remained as permanent strain after unloading. On the other hand, crystal lattice strain showed a different behavior for macroscopic strain; it kept a constant value after instantaneous deformation due to loading and then increased gradually after a certain period of time. These differences between macroscopic and microscopic levels were never found in the stress relaxation tests in this study. Relaxation modulus at the macroscopic level only showed a decreasing trend throughout the relaxation process. However crystal lattice strain kept a constant value during the macroscopic relaxation process. In addition, the microfibril angle (MFA) of wood cell wall has a role of mechanical behavior at microscopic level; crystal lattice strains were smaller with increasing MFA at both creep and relaxation processes. Creep compliance and stress relaxation modulus at the macroscopic level decreased and increased with increasing MFA, respectively. Our results on the viscoelastic behavior at microscopic level evidenced its dependency on MFA. 相似文献
97.
Effect of dietary kapok oil supplementation on growth performance,carcass traits,meat quality and sensory traits of pork in finishing‐pigs 下载免费PDF全文
Keisuke Maeda Kimiko Kohira Hiroki Kubota Kousuke Yamanaka Kaoru Saito Masakazu Irie 《Animal Science Journal》2017,88(8):1066-1074
Kapok seed and oil from the tropical zone are widely used as pig feed to harden porcine fat in Japan. This study evaluated the effect of dietary kapok oil supplementation on pork quality and sensory traits. Five Duroc pigs each were assigned to an experimental group supplemented with kapok oil and a control group. Dietary kapok oil supplementation had no effect on growth performance and intramuscular fat content in the Longissimus dorsi muscle (LM). Supplemental kapok oil increased saturated fatty acid contents in subcutaneous and intramuscular fat and decreased monounsaturated fatty acid levels (P < 0.05). Off‐flavor detection by a trained panel was higher in the experimental than the control group (P < 0.05), but tenderness, juiciness, texture and flavor intensity of LM chops were similar in both groups. The overall palatability of pork as judged by a consumer panel decreased with kapok oil supplementation (P < 0.01). These results indicate that while growth performance, intramuscular fat contents and carcass characteristics were unchanged, while dietary kapok oil supplementation makes firm fat to prevent inferior soft fat in pork, it can lower the palatability of pork due to a decrease in monounsaturated fatty acids. 相似文献
98.
In water-saving rice culture, yield is unstable because spikelet number per unit area and grain weight fluctuate according to water availability. In this study, we investigated the factors that determine grain weight in aerobic culture. We grew four rice varieties in non-puddled, unsaturated (aerobic) soils with a soil water potential at 20-cm depth kept above −60 kPa and in continuously flooded culture in two years. We found a significant variety × water interaction in grain weight in 2009: weights under aerobic culture were 6% and 13% larger than under flooded culture in Sasanishiki and IRAT109, respectively, versus 4% and 10% smaller in Habataki and Takanari. There was no significant variety × water interaction in grain weight in 2010. Sink activity (grain sucrose synthase activity) and source capacity (biomass production and nonstructural carbohydrate content in vegetative tissue) per plant during ripening were higher under aerobic culture than under flooded culture in both years. However, an excessive increase in spikelet number per unit area in Takanari under aerobic culture in 2009 reduced the source capacity per spikelet and single husk size, decreasing grain weight. In 2010, frequent soil drying under aerobic culture during the late reproductive period (around 20 days preceding heading) reduced single husk size, thereby decreasing grain weight. We found that sink activity and source capacity per plant could be both higher under aerobic culture during the ripening period, producing larger grain weight at a soil water potential above-40 kPa at a 20-cm depth relative to those under flooded culture. In contrast, greater drying under aerobic culture during the late reproductive period reduced single husk size, thereby reducing grain weight. 相似文献
99.
Yoichiro Kato Amelia HenryDaisuke Fujita Keisuke KatsuraNobuya Kobayashi Rachid Serraj 《Field Crops Research》2011,123(2):130-138
Water scarcity threatens sustainable rice production in many irrigated areas around the world. To cope with the scarcity, aerobic rice culture has been proposed as a promising water-saving technology. The objective was to elucidate the physiological attributes behind the performance of rice introgression lines in water-saving culture. We evaluated yield potential and physiological adaptation traits to water deficit of BC3-derived lines with the genetic background of an elite indica cultivar, IR64, in the field and in pot experiments. One line, YTH183, had 26% higher yield than IR64 under non-stress conditions (895 vs. 712 g m−2 on average). This was attributed to enlarged sink capacity due to large grain size, which contributed to more efficient use of assimilates and hence a higher harvest index. YTH183 also showed better dehydration avoidance under intermittent soil drying, due to the adaptive response of deep rooting to water deficiency. The grain yield of YTH183 exceeded that of IR64 by 92-102% under moderate water deficit caused by limited irrigation in aerobic rice culture (143 vs. 72 g m−2). Two introgressed segments on chromosomes 5 and 6 might, at least in part, confer the higher yield potential and greater dehydration avoidance in YTH183 simultaneously. Advanced backcross breeding combined with molecular genetics and physiological characterization of introgressed segments would be effective for developing new rice cultivars with high yield potential and drought adaptation traits. 相似文献
100.
Keisuke Kojiro Tsunehisa Miki Hiroyuki Sugimoto Masamitsu Nakajima Kozo Kanayama 《Journal of Wood Science》2010,56(2):107-111
To investigate micropores and mesopores in the cell walls of dry wood, CO2 gas and N2 gas adsorption onto dry wood were measured at ice-water temperature (273 K) and liquid nitrogen temperature (77 K). CO2 gas adsorption isotherms obtained were used for determining micropore volumes smaller than 0.6 nm by the HK method (Horvath-Kawazoe
method), and N2 gas adsorption isotherms obtained were used for determining the mesopore volume between 2 nm and 50 nm by the Barrett-Joyner-Halenda
(BJH) method. Micropores and mesopores existed in cell walls of dry wood, and the cumulative pore volume was much larger for
micropores than for mesopores. Micropores in the cell wall of dry wood decreased with elevating heat treatment temperature,
and the decreased micropore was reproducible by wetting and drying. Mesopores did not decrease so much with elevating heat
treatment temperature. Micropore volumes for the softwood Hinoki and the hardwood Buna were compared. A larger amount of micropores
existed in hardwood Buna than in softwood Hinoki, and this relationship was considered to correspond to the difference in
thermal softening properties for lignin in water-swollen Hinoki and Buna. This result probably indicates that micropores in
the cell walls of dry wood relate to the structure of lignin. 相似文献