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81.
TANG Jiu-you JIANG Ling ZHANG Wen-Wei WANG Chun-ming LIU Shi-jia CHEN Liang-Ming ZHAI Hu-qu Atsushi Yoshimura WAN Jian-min 《中国农业科学(英文版)》2004,3(9)
Quantitative trait loci(QTL)controlling seed dormancy in rice were identified using recombinant inbred lines(RILs)population derived from the cross between a japonica variety Kinmaze and an indica variety DV85. Seeds of two parental cultivars and each RIL were harvested in 35d after heading.. The germination percentage of these seeds at 30℃for 7 days were measured as the degree of seed dormancy.. QTL analysis was performed with Windows QTL Cartographer 1.13a program by composite interval mapping.. A total of four QTL for seed dormancy were detected on chromosome 2(two regions),5 and 11,respectively.Phenotypic variation explained by each QTL ranged from 8.37 to 17.40%.. Responses of such loci to a dormancy-breaking treatment with dry heat were further detected. The results showed that two alleles of qDOR-2-1 and qDOR-5 from DV85 as well as the allele of qDOR11 from Kinmaze increased the seed dormancy,which seemed to be easily broken by dry heat treatment. Such loci of seed dormancy may be applied to rice genetic improvement.The allele of qDOR-2-2 from DV85 increased the seed dormancy,which could not be broken by dry heat treatment. 相似文献
82.
Yasushi?HiramatsuEmail author Kiyohiko?Fujimoto Atsushi?Miyatake Kenta?Shindo Hirofumi?Nagao Hideo?Kato Hirofumi?Ido 《Journal of Wood Science》2011,57(1):66-70
The purpose of this study was to investigate the strength properties of glued laminated timber composed of edge-glued laminae
and to investigate the influence of edge gluing on the strength properties. Glued laminated timber composed of multiple-grade
laminae (symmetrical composition, strength grade E95-F270, 10 laminations) was produced from karamatsu (Larix kaempferi) edge-glued laminae according to the Japanese Agricultural Standard. The bending, tensile, and compressive strengths of the
glued laminated timber were measured. The average bending, tensile, and compressive strengths were 33.4, 24.5, and 35.9 MPa,
respectively, and these values are almost equal to those of glued laminated timber composed of karamatsu single-piece laminae.
It was determined that finger-joints and knots in the edge-glued laminae played a significant role in the failure of specimens.
However, the use of glued edge-joints did not appear to affect the failure of specimens. 相似文献
83.
Hiroyuki KOBAYASHI Atsushi EGUCHI Wataru TAKANO Masahiro SHIBATA Motoni KADOWAKI Shinobu FUJIMURA 《Animal Science Journal》2011,82(1):86-92
The major taste active component, glutamate (Glu), improves the taste of meat. In this study, we investigated the effect of a short‐term high‐protein (HCP) diet on the intramuscular free Glu content to improve the taste of meat. Furthermore, we elucidated how the muscle free Glu content was controlled by the HCP diet. Chicks (14 days old) were fed the control diet or HCP diet for 10 days. Plasma and muscle free amino acid concentrations, and activity and messenger RNA (mRNA) expression of muscle enzymes related to Glu metabolism were determined. Muscle free Glu content was increased (P < 0.01) by 51%. Activity and mRNA expression of glutaminase (GA), which is one of the major Glu‐related enzymes, were significantly decreased (P < 0.05) in the HCP group because of feedback inhibition. The mRNA expression of lysine α‐ketoglutarate reductase (LKR), which is the enzyme involved in lysine (Lys) degradation and Glu production, was significantly increased (P < 0.001) in the HCP group. These results suggest that short‐term dietary HCP feeding is an effective treatment for improving the taste of meat. Furthermore, our results suggest that the free Glu content in muscle is regulated by GA and LKR. 相似文献
84.
Kuko Fuke Kana Takeshita Nanako Aoki Toshiyuki Fukuhara Mayumi Egusa Motoichiro Kodama Hiromitsu Moriyama 《Journal of General Plant Pathology》2011,77(4):248-252
Strains of the Japanese pear pathotype of Alternaria alternata were screened for double-stranded RNAs (dsRNAs). Four strains had several dsRNAs; strain N18 was associated with several
dsRNAs and had impaired growth phenotypes such as irregular mycelium and abnormal pigmentation. We isolated dsRNA-cured isolates
from strain N18 by single-conidium isolation. The dsRNA-cured isolates had recovered normal growth and pigmentation. Enlarged
vesicles were observed in mycelial cells of the original dsRNA-carrying N18 strain. DAPI nuclear staining revealed regression
of the nuclei in dsRNA-carrying N18 cells. These results indicate that the dsRNAs might have negative effects, such as apoptosis-like
cell death, on the host fungus. 相似文献
85.
Bollinger DW Tsunoda A Ledoux DR Ellersieck MR Veum TL 《Journal of agricultural and food chemistry》2004,52(7):1804-1809
A simplified in vitro test tube (TT) method was developed to estimate the percentage of available P in feed ingredients for swine. The entire digestion procedure with the TT method consists of three consecutive enzymatic digestions carried out in a 50-mL conical test tube: (1) Pre-digestion with endo-xylanase and beta-glucanase for 1 h, (2) peptic digestion for 2 h, and (3) pancreatic digestion for 2 or 4 h. The TT method is simpler and much easier to perform compared to the dialysis tubing (DT) method, because dialysis tubing is not used. Reducing sample size from 1.0 to 0.25 g for the TT method improved results. In conclusion, the accuracy and validity of the TT method is equal to that of our more complicated DT method (r = 0.97, P < 0.001), designed to mimic the digestive system of swine, for estimating the availability of P in plant-origin feed ingredients. 相似文献
86.
Atsushi Ikegaya Tomoaki Kawata Toru Ikari Yuji Emoto Yosuke Sato Takashi Takeuchi 《Soil Science and Plant Nutrition》2020,66(3):449-457
ABSTRACT The fertilizer absorption characteristics of strawberries are not clear, although appropriate fertilization is definitely necessary to ensure produce quality and quantity. This study aimed to determine the amounts of macro- and micronutrients absorbed during cultivation of strawberries and their biodistribution and utilization in the plant body. We cultivated Japanese strawberries ‘Benihoppe’ and ‘Kirapika’ in small hydroponic equipment containing a nutrient solution and determined the amounts of N, P, K, Ca, Mg, Fe, Mn, B, Zn, Cu, and Mo absorbed during and at the end of cultivation. The results revealed the adsorption levels of these elements during the cultivation period. The nutrient concentrations varied greatly among plant organs. In particular, P and B accumulated at high levels in the leaves and stem, K, Ca, Mg, Mn, Zn, and Cu accumulated in the crown, and N, Fe, and Mo accumulated in the roots. In addition, the uptake levels of N, P, K, Mg, Mn, Zn, and Cu differed between Benihoppe and Kirapika. Our results provide useful information for determining fertilizer application rates in strawberry cultivation. 相似文献
87.
Preparation of phytate-removed deamidated soybean globulins by ion exchangers and characterization of their calcium-binding ability. 总被引:3,自引:0,他引:3
Hitomi Kumagai Shigeo Ishida Atsushi Koizumi Hidetoshi Sakurai Hitoshi Kumagai 《Journal of agricultural and food chemistry》2002,50(1):172-176
Phytate-removed deamidated soybean globulins were prepared using ion-exchange resins to provide them with a functional property to enhance calcium absorption in the body. The phosphorus level was reduced from 45 to 20 micromol/g using 0.05 g/mL of AE-4, an anion-exchange resin with a (2-hydroxyethyl)dimethylammonium group, in 0.2% soybean globulin solution for 1 h at 4 degrees C, and 90-92% of the phosphorus in defatted soybeans could be removed. As for deamidation, CE-4, a cation-exchange resin of the carboxylate type, showed a much higher deamidation activity than CE-1 and CE-2, cation-exchange resins of the sulfonate type. No peptide bond hydrolysis was observed for any cation-exchange resin treated at 4 degrees C. There was no significant difference in the amount of acid amide deamidated at temperatures between 4 and 50 degrees C. The deamidation level was able to increase to 73% using 0.10 g/mL of CE-4 in a 0.2% soybean globulin solution for 6 h at 4 degrees C. The amount of calcium bound to the soybean globulins decreased with removal of the phytate but increased with deamidation. 相似文献
88.
Hideomi Kodama Catherine A. Fox Charles Tarnocai Frederick J. Longstaffe 《植物养料与土壤学杂志》1992,155(5):401-406
The occurrence of quartz particles having a platy morphology found in the white layers within the fossil forest deposits of Axel Heiberg Island, was further confirmed by optical and electron microscopic examinations. The platy quartz crystals were concentrated in the finer fractions. The δ 18O values of fractions enriched in platy quartz crystals ranged from +13.7 to +16.6 %0. These values were higher than those obtained for coarser fractions. The platy morphology and crystallographic character of the quartz particles concentrated in the finer size fractions are uncharacteristic both of aerosol derived material and of secondary silica. These findings and information available for the paleoenvironment of the study area favor a biogenic origin for the platy quartz. The oxygen-isotope data are consistent with this hypothesis. 相似文献
89.
Turmeric oil was extracted from turmeric (Curcuma longa) with supercritical carbon dioxide in a semicontinuous-flow extractor. Extraction rate was measured as a function of pressure, temperature, flow rate, and particle size. The extraction rate increased with an increase in CO(2) flow rate and with a reduction of particle size. The effect of pressure and temperature on turmeric extraction suggested the use of higher pressure and lower temperature at which solvent density is greater and thus the solubility of the oil in the solvent is greater in the range of 313-333 K and 20-40 MPa. The major components ( approximately 60%) of the extracted oil were identified as turmerone and ar-turmerone by GC-MS. 相似文献
90.
Kawabata J Okamoto Y Kodama A Makimoto T Kasai T 《Journal of agricultural and food chemistry》2002,50(19):5468-5471
DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging reactions of protocatechuic and gallic acids, and their methyl esters, have been investigated by NMR. In acetone, methyl protocatechuate was gradually converted to a Diels-Alder adduct of two molecules of the intermediate quinone in the reaction with DPPH radical, whereas methyl gallate rapidly gave a symmetrical dimer via a putative quinone precursor. Both dimers are rather unstable and their structures have been deduced by in situ NMR measurements of the reaction mixtures. Gallic acid also gave a corresponding symmetrical dimer in the same reaction as methyl gallate, although protocatechuquinone produced from protocatechuic acid did not yield a Diels-Alder adduct, unlike its methyl ester. Interestingly, these dimer formations were not observed in methanol solution. 相似文献