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121.
The shattering habit in buckwheat occurs because of brittle or weak pedicels. Brittle pedicels are observed in wild buckwheat
but not in cultivated buckwheat. Using 2 self-compatible lines, 01AMU2 with brittle pedicels and Kyukei SC2 (KSC2) with non-brittle
pedicels, produced by an interspecific cross between Fagopyrum esculentum cv Botansoba (non-brittle) andF. homotropicum (brittle), we investigated the inheritance of brittle pedicels. F1 plants derived from crosses between Botansoba × 01AMU2 and Botansoba × KSC2 had brittle pedicels. The F2 population derived from the cross between Botansoba × 01AMU2 showed segregation of brittle and non-brittle pedicels that
fit the expected 3:1 ratio, suggesting that non-brittle pedicel in Botansoba is controlled by a single recessive gene (sht1). Another F2 population, derived from the cross between Botansoba × KSC2, showed segregation of brittle and non-brittle pedicels that
fit an expected ratio of 9:7,suggesting that non-brittle pedicel in KSC2is controlled by a different single recessive gene
(sht2). Thus, brittle pedicel is achieved by 2 complementary genes Sht1 and Sht2. The sht1 locus is linked to the S locus with a recombination frequency of5.46±1.18 (%). We investigated whether common buckwheat has the allele sht2by crossing 6 common buckwheat lines withKSC2. An analysis of the preliminary data showed that some of the F1 had brittle pedicels and others had non-brittle pedicels, suggesting that some common buckwheat lines possess both the allelesSht2 and sht2.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
122.
Atsushi Sakai Takahisa Hirayama Shigenori Oshioka Yasumasa Hirata 《Journal of Forest Research》2006,11(4):253-265
Large areas of previously clear-cut conifer plantations have been recently abandoned in Japan. We investigated the vegetation
in the clear-cut sites and examined the environmental factors affecting species composition of the vegetation. We set up 32
study sites, each composed of several study plots (5 × 5 m), ranging from 220 m to 1060 m a.s.l. Elevation and warmth index
(cumulated thermal quantity) were the primary factors affecting the species composition, with clear-cut areas showing a smaller
effect in the nonmetric multidimensional scaling (NMS) ordination. Two-way indicator species analysis (TWINSPAN) divided the
32 study sites into ten vegetation groups, clustering the sites by elevation or by postharvest disturbances (i.e., replanting
or browsing of Sika deer). Deciduous trees and shrubs were significant in the vegetation cover at higher elevations, while
they were less so in areas of high Sika deer populations. We also investigated the abundance of old-growth species, which
are expected to regenerate where the clear-cut site is abandoned. Evergreen Quercus and Castanopsis saplings were abundant at low elevations (<600 m), suggesting that they will successfully regenerate. The sapling densities
of Abies firma and Betula grossa were significantly large where a clear-cut site was adjacent to natural forest, which is expected to act as a seed source.
This implies that degraded deciduous forests may establish after clear-cutting at intermediate and high elevations (>600 m)
if the clear-cut site is distinct from seed sources. It is argued that the preservation of natural forests is critical for
the regeneration of old-growth species. 相似文献
123.
Takahisa Nakai Hisashi Abe Takeshi Muramoto Tetsuya Nakao 《Journal of Wood Science》2005,51(5):441-447
The relationship between sap flow rates and diurnal fluctuation of stems was investigated in cloned 3-year-old saplings of
Cryptomeria japonica D. Don grown in a phytotron with irrigation every 2 days. The improved stem heat balance method and a strain gauge were used
to measure sap flow rate and diurnal fluctuation of the stem. The sap flow rate reacted to lighting conditions, increasing
and decreasing immediately after lights-on and lights-off, respectively. The tangential strain on the surface of the inner
bark exhibited a reaction that followed but opposed the reaction of the sap flow rate to lighting conditions. Based on the
changes in sap flow rate, there seemed to be four phases in diurnal sap flow: phase A1 began with lights-on, when the sap flow rate increased, and lasted about 2 hours. In the following phase, A2, the sap flow rate remained almost constant at 1.3 g/min for about 10 h, and then declined for about 2 h as lights-off approached.
In phase B, the early period of darkness, the sap flow declined quickly and then more slowly, for about 4 h, until the start
of the second dark period, phase C, when the sap flow rate became almost constant at 0.05 g/min for about 6 h. The first derivative
of each sap flow rate and the corresponding tangential strain were calculated, and the results indicated a negative correlation
between the two variables in all periods. In particular, the relationship between the first derivative values exhibited a
highly negative correlation in phases A1 and B, expressed as a primary formula. Sap flow rate was found to continue for some time after lights-off, and this compensated
for reduced evaporative effects, albeit at a slow rate, over 4 h. The total amount of sap flow in the dark was only about
9% of that in the light, disregarding transpiration in the dark for simplicity. Thus, the total amount of sap flow responsible
for swelling of the stem was about 9% of that consumed in transpiration during the light period. 相似文献
124.
Yingcheng Hu Tetsuya Nakao Takahisa Nakai Jiyou Gu Fenghu Wang 《Journal of Wood Science》2005,51(1):13-17
Wood plastic plywood (WPPW), composed of veneer and styrofoam, was manufactured without special adhesives such as urea–formaldehyde or phenol–formaldehyde resins, and its vibrational properties were investigated. WPPW can be produced at 1MPa and 160°C for 9min (three-ply) and 12min (five-ply). The dynamic Youngs modulus reached its highest value when the styrofoam thickness was 30mm. The sound velocity and dynamic Youngs modulus had minimum values at a grain angle of 45°. The results for dynamic Youngs moduli measured by a longitudinal vibration method and an in-plane flexural vibration method were almost the same. Dynamic shear moduli were measured by an in-plane surface wave propagation test and an in-plane flexural vibration method. From the experimental results, the dynamic shear moduli at 0° and 90° by the two methods were relatively close, although the surface wave propagation test results were higher than those from the flexural vibration method. Dynamic shear moduli at a grain angle of 45° measured by the in-plane surface wave propagation test and calculated from theory were relatively close. The surface wave propagation test results were smaller than the results calculated from theory. The shear stress distribution factors were about 1.000–1.189 for WPPW. 相似文献
125.
Effects of grain angles of face veneer on surface wave velocities and dynamic shear moduli of wood-based composites 总被引:1,自引:0,他引:1
Yingcheng Hu Tetsuya Nakao Takahisa Nakai Jiyou Gu Fenghu Wang 《Journal of Wood Science》2005,51(3):286-289
The effects of grain angle of face veneer on surface wave velocity and dynamic shear modulus of three types of wood-based composites were examined using a surface wave propagation method. It was found that grain-angle dependence of surface wave velocity and dynamic shear modulus indeed exists for wood-based composites. Grain angles of face veneer were found to have substantial effects on the surface wave velocities and dynamic shear moduli of wood–plastic composite (WP), wood–fiberboard composite (WF), and wood–metal composite (WM). The orthotropic properties of the three composites were defined as the ratio of surface wave velocities at 0° and 90° grain angles (V0/V90), which were 3.7, 2.2, and 2.0 for WP, WF, and WM, respectively. For WP, WF, and WM, the dynamic shear moduli in the 90° grain angle of face veneer were approximately 7%, 19%, and 25% of that in the 0° grain angle, respectively. The relationships between grain angles of face veneer and the shear moduli of the three types of wood-based composites could be represented by Hankinson’s equation, and their optimal n values were 2.1, 1.2, and 1.3 for WP, WF, and WM, respectively.Part of this study was presented at the 15th Annual Meeting of the Chugoku Shikoku Branch of the Japan Wood Research Society, Higashi-Hiroshima, Japan, September 2003 相似文献
126.
Teruko Konishi Tomonori Nakai Fukumi Sakai Takahisa Hayashi 《Journal of Wood Science》2001,47(5):331-335
Callose is formed from exogenous sucrose by cotton fiber microsomal membranes that contain both sucrose synthase and callose synthase activity. Although the coupled reaction between sucrose and callose synthases occurs predominantly to channel glucose from sucrosederived uridine diphosphate (UDP)-glucose into callose in the membranes, there is no difference in the UDP-glucose-forming/sucrose-forming activity ratios between the soluble and membrane-bound forms of sucrose synthase. The consumption of UDP-glucose from sucrose into callose probably leads to UDP-glucose formation rather than sucrose formation despite the lower affinity of sucrose synthase for sucrose than for UDP-glucose. Callose formation is markedly stimulated by the addition of either recombinant Glu11 (S11E) or in vitro phosphorylated Ser11 mung bean sucrose synthase but not by the wild-type nonphosphorylated Ser11 enzyme. We propose that a negative charge (by phosphorylation or mutagenesis) at Ser11 in sucrose synthase causes the enzyme to promote a coupled callose-forming reaction.Part of this paper was presented at the 8th International Cell Wall Meeting, Norwich, UK, September 1998 相似文献
127.
Yoshiyuki IMURA Satoko IGUCHI Kazuhiro TOYODA Yuki ICHINOSE Tomonori SHIRAISHI Tetsuji YAMADA 《Journal of General Plant Pathology》2000,66(2):123-127
Regulatory elements in the promoter of phenylalanine ammonia-lyase gene 1 of pea (PSPAL1) in response to nonpathogenic attack were identified by in vivo footprinting analysis. The footprints determined AC-rich sequences, Box-I and Box-II, that were conserved at similar positions
in the phenylpropanoid gene promoters from several plants. To reveal the functions of the AC-rich sequence in nonpathogen-responsiveness,
we constructed Box-I-deletion PSPAL1 promoter (dB-1) with GUS reporter gene and transformed it into tobacco plant. The dB-1 had reduced basal expression and a complete loss of nonpathogen-responsiveness. These results indicate the essentiality of
Box-I for PSPAL1 activation induced by nonpathogenic attack.
Received 27 October 1999/ Accepted in revised form 25 November 1999 相似文献
128.
The beta- and gamma-analysis methods were fully tested on nineteen British soils; ‘marker’ gamma photo-peaks of daughter-elements were used for estimating Th and U, and the 1.46 MeV?40K photo-peak for K. The photo-peaks for Th and U that give values for the K contents of the soil closest to the chemically determined values are 208Tl(ThC″)–2.615 MeV and 214Bi(RaC)+–0.609 MeV respecively. Reasonable values for the Th content of these soils are obtained by this method, but U contents seem to be considerably overestimated. 相似文献
129.
Tomomi Kaku Rumi Kaida Kei��ichi Baba Sri Hartati Enny Sudarmonowati Takahisa Hayashi 《Journal of Wood Science》2011,57(6):545-548
Recalcitrance to saccharifi cation is a major limiting factor of the conversion of lignocellulosic biomass to ethanol. Levels of wood saccharification and subsequent ethanol production were higher in transgenic mangium (Acacia mangium) trees overexpressing xyloglucanase than in wild-type plants, even after delignification of the wood. We propose that a decrease in the quantity of xyloglucan that is intercalated into cellulose microfibrils could facilitate the process of saccharification. 相似文献
130.
Body weight and fatness are quantitative traits of agricultural and medical importance. In previous genome‐wide quantitative trait locus (QTL) analyses, two QTLs for body weight and weight gain at an early postnatal growth period were discovered on mouse chromosome 10 from a gene pool of wild subspecies mice, Mus musculus castaneus. In this study, we developed a congenic strain with an approximately 63‐Mb wild‐derived genomic region on which the two growth QTLs could be located, by recurrent backcrossing to the common inbred strain C57BL/6J. We compared body weights at 1–10 weeks of age, body weight gains at 1–3, 3–6 and 6–10 weeks, internal organ weights and body lengths between the congenic strain developed and C57BL/6J. Unfortunately, no effects of the two growth QTLs on body weights and weight gains were confirmed. However, at least two new QTLs affecting fatness traits were discovered within the introgressed congenic region. The wild‐derived allele at one QTL increased body mass index, whereas at another one it decreased white fat pad weight and adiposity index. Thus, the congenic mouse strain developed here is a useful model animal for understanding the genetic and molecular basis of fat deposition in livestock as well as humans. 相似文献