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排序方式: 共有357条查询结果,搜索用时 15 毫秒
1.
2.
Takayoshi?OharaEmail author Yeon-Sang?Song Hikaru?Tsukazaki Tadayuki?Wako Tsukasa?Nunome Akio?Kojima 《Euphytica》2005,144(3):255-263
Summary The first genetic linkage map of Japanese bunching onion (Allium fistulosum) based primarily on AFLP markers was constructed using reciprocally backcrossed progenies. They were 120 plants each of (P1)BC1 and (P2)BC1 populations derived from a cross between single plants of two inbred lines: D1s-15s-22 (P1) and J1s-14s-20 (P2). Based on the (P2)BC1 population, a linkage map of P1 was constructed. It comprises 164 markers – 149 amplified fragment length polymorphisms (AFLPs), 2 cleaved amplified polymorphic
sequences (CAPSs), and 12 simple sequence repeats (SSRs) from Japanese bunching onion, and 1 SSR from bulb onion (A. cepa) – on 15 linkage groups covering 947 centiMorgans (cM). The linkage map of P2 was constructed with the (P1)BC1 population and composed of 120 loci – 105 AFLPs, 1 CAPS, and 13 SSRs developed from Japanese bunching onion and 1 SSR from
bulb onion – on 14 linkage groups covering 775 cM. Both maps were not saturated but were considered to cover the majority
of the genome. Nine linkage groups in P2 map were connected with their counterparts in P1 map using co-dominant anchor markers, 13 SSRs and 1 CAPS. 相似文献
3.
We demonstrated that the inorganic phosphate (P(i)) requirement for growth of Japanese red pine (Pinus densiflora Sieb. & Zucc.) seedlings is increased by elevated CO(2) concentration ([CO(2)]) and that responses of the ectomycorrhizal fungus Pisolithus tinctorius (Pers.) Coker & Couch to P(i) supply are also altered. To investigate the growth response of non-mycorrhizal seedlings to P(i) supply in elevated [CO(2)], non-mycorrhizal seedlings were grown for 73 days in ambient or elevated [CO(2)] (350 or 700 micromol mol(-1)) with nutrient solutions containing one of seven phosphate concentrations (0, 0.02, 0.04, 0.06, 0.08, 0.10 and 0.20 mM). In ambient [CO(2)], the growth response to P(i) was saturated at about 0.1 mM P(i), whereas in elevated [CO(2)], the growth response to P(i) supply did not saturate, even at the highest P(i) supply (0.2 mM), indicating that the P(i) requirement is higher in elevated [CO(2)] than in ambient [CO(2)]. The increased requirement was due mainly to an altered shoot growth response to P(i) supply. The enhanced P(i) requirement in elevated [CO(2)] was not associated with a change in photosynthetic response to P(i) or a change in leaf phosphorus (P) status. We investigated the effect of P(i) supply (0.04, 0.08 and 0.20 mM) on the ectomycorrhizal fungus P. tinctorius in mycorrhizal seedlings grown in ambient or elevated [CO(2)]. Root ergosterol concentration (an indicator of fungal biomass) decreased with increasing P(i) supply in ambient [CO(2)], but the decrease was far less in elevated [CO(2)]. In ambient [CO(2)] the ratio of extramatrical mycelium to root biomass decreased with increasing P(i) supply but did not change in elevated [CO(2)]. We conclude that, because elevated [CO(2)] increased the P(i) requirement for shoot growth, the significance of the ectomycorrhizal association was also increased in elevated [CO(2)]. 相似文献
4.
Protoplasts were isolated from the leaves of sterile plants ofPopulus euphratica Oliv. by using 1% Cellulase “Onozuka” RS and 0.25% Pectolyase Y-23 in 0.6m of mannitol solution. Protoplasts were cultured in modified Murashige and Skoog's (MS) medium which contained no ammonium
ions but was supplemented with BAP (6-benzylaminopurine), 2,4-D (2,4- dichlorophenoxy-acetic acid), and 1% sucrose at the
cell density of 9×104/ml. Cell divisions occurred in every culture medium, especially in the medium containing 0.5 mg/l of BAP and 0.1 mg/l of
2,4-D, in which callus was successfully induced by successive culture through cell cluster formation. Shoots were regenerated
from the callus, and their growth was enhanced on 1/2 MS medium containing 0.8 mg/l of BAP. Finally, shoots were rooted and
plantlets were regenerated on 1/2 MS medium without a hormone.
A part of this paper was presented at the 106th Annual Meeting of the Jpn. For. Soc. (1995). 相似文献
5.
T. Ona T. Sonoda K. Ito M. Shibata Y. Tamai Y. Kojima J. Ohshima S. Yokota N. Yoshizawa 《Wood Science and Technology》2001,35(3):229-243
Relationships between cell and pulp properties were investigated by examining the within-tree property variations in Eucalyptus camaldulensis and Eucalyptus globulus. Properties investigated included proportions of ray and axial parenchyma, thickness of cell walls and cell wall percentages.
The characteristics of the ray and axial parenchyma (their proportions and wall thickness) were found to have a significant
influence on all measured pulp properties, including paper strength properties. Multiple regression of pulp properties in
relation to cell properties revealed that nearly all measured pulp properties were explained by cell properties at the 1%
significance level. It was concluded, therefore, that all cell types are important for predicting pulp properties, and it
is strongly recommended that tree breeding programs for Eucalyptus include the measurement of all cell types.
Received 6 July 1999 相似文献
6.
Evaluating the durability of wood-based panels using internal bond strength results from accelerated aging treatments 总被引:1,自引:0,他引:1
In this study, the durability of wood-based panels was evaluated by comparing the internal bond (IB) strength retention after
five different laboratory-based accelerated aging tests with the IB retention after 5 years of outdoor exposure in Shizuoka
City. In each accelerated aging test, the IB retention of MDI-bonded panels showed high retention compared to other panels.
Outdoor exposure in Shizuoka City resulted in an IB retention value for particleboard (PF) and oriented strandboard (aspen)
of less than 10% after the 5-year exposure period. Medium-density fiberboards maintained their initial IB strength over the
same period. Calculation of the mean IB retention for all board types allowed comparison of the severity of aging between
the accelerated test methods and outdoor exposure. The ASTM six-cycle test method was the most severe among the standard treatment
cycles applied. 相似文献
7.
8.
Isolation of some glycosides as aroma precursors in young leaves of Japanese pepper (Xanthoxylum piperitum DC.). 总被引:4,自引:0,他引:4
L Jiang H Kojima K Yamada A Kobayashi K Kubota 《Journal of agricultural and food chemistry》2001,49(12):5888-5894
To clarify the formation mechanism for the major alcoholic aroma compounds in young leaves of Japanese pepper, the glycosides were isolated as aroma precursors. The presence of glycosides of the main alcoholic aroma constituents was indirectly determined by enzymatic hydrolysis and trifluoroacetylation (TFA) of the glycoside-containing fraction. After Amberlite XAD-2 column chromatography, ODS flash chromatography, and high-performance liquid chromatography (HPLC), two new compounds, namely, (3S,6S)-cis-linalool-3,7-oxide beta-D-glucopyranoside and 2-methylpropanyl 6-O-beta-D-apiofuranosyl-beta-D-glucopyranoside, were isolated. In addition, (3S,6R)-cis-linalool-3,6-oxide beta-D-glucopyranoside, which absolute configuration was the first determined, and six known glycosides, citronellyl beta-D-glucopyranoside, linalyl 6-O-beta-D-apiofuranosyl-beta-D-glucopyranoside, (Z)-3-hexenyl beta-D-glucopyranoside, benzyl 6-O-beta-D-apiofuranosyl-beta-D-glucopyranoside, dendranthemoside A, and 3,6-dihydroxy-5,6-dihydro-beta-ionol 9-beta-D-glucopyranoside, were isolated. All of these glycosides were isolated for the first time from the leaves of Japanese pepper. Their structures were established on the basis of spectral data and chemical evidence. The ratios of stereoisomers of the aglycon moieties of citronellyl beta-D-glucopyranoside and linalyl 6-O-beta-D-apiofuranosyl-beta-D-glucopyranoside were investigated by a chiral GC analysis and compared with those of free citronellol and linalool in the aroma concentrate. 相似文献
9.
10.
Maria Rowena R. Romana-Eguia Minoru Ikeda Zubaida U. Basiao Nobuhiko Taniguchi 《Aquaculture International》2010,18(6):1205-1221
Growth of several genetically improved Nile tilapia (GIFT or Genetically Improved Farmed Tilapia, FaST or Freshwater Aquaculture
Center Selected Tilapia, SEAFDEC-selected) and domesticated red tilapia (BFS or Binangonan Freshwater Station, NIFI-red or
National Inland Fisheries Institute red, HL or Hacienda Luisita) stocks were compared in controlled (tank) and uncontrolled
farm conditions (lake-based cages) with unselected NIFI or Chitralada Nile tilapia as control. Specific growth rate differed
significantly (P = 0.009) in tank-reared Nile tilapia stocks where GIFT grew best at 1.358%/day followed by FaST (1.307%/day), control stock
NIFI (1.257%/day) and SEAFDEC-selected (1.202%/day). Genetic effect explained 84.4% of the variance in growth of Nile tilapia
in tanks. Although Nile tilapia growth in cages followed the same trend where GIFT grew best at 1.570%/day, no significant
stock differences (P = 0.479) were noted. Meanwhile, red tilapia reared in either tanks or cages showed no significant stock differences in terms
of growth. However, survival of the red tilapia stocks in cages differed significantly with HL having the highest percentage
survival at 93.3%. The different growth responses of the Nile tilapia stocks especially under controlled (tank) farm conditions
were largely due to genetic factors (stock differences).Under uncontrolled farm conditions, environmental factors were generally
observed to have also affected the survival and to some extent, the growth of Asian Nile and red tilapia stocks. 相似文献