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141.
Influence of High Shoot and Root-Zone Temperatures on Growth of Three Wheat Genotypes during Early Vegetative Stages 总被引:1,自引:0,他引:1
I. S. A. Tahir N. Nakata T. Yamaguchi J. Nakano & A. M. Ali 《Journal of Agronomy and Crop Science》2008,194(2):141-151
High temperatures, whether of shoot or root, are reported to affect shoot and root growth of various plant species. The scanty information available on the differential response of wheat genotypes to high shoot and root‐zone temperatures triggered this investigation to study the response and adaptation of shoot and root growth of three wheat genotypes to high shoot and root‐zone temperatures during early growth stages. Three wheat genotypes; Fang (heat tolerant), Siete Cerros (heat sensitive) and Imam (recent cultivar adapted to a hot irrigated environment) were grown in soil and hydroponically. Three shoot/root‐zone temperatures (23/23, 23/35 and 35/35 °C for the soil experiment and 22/22, 22/38 and 38/38 °C for the hydroponic experiment) were applied at three‐leaf growth stage. High root‐zone temperature alone or combined with high shoot temperature reduced xylem sap flow rate, root dry weight, root length and root/shoot ratio. Unexpectedly, shoot fresh and dry weights and relative growth rate (RGR) were not significantly affected by the high root‐zone temperature except for the susceptible genotype, Siete Cerros, after prolonged exposure in the hydroponic experiment. In contrast, high shoot/root‐zone temperature significantly reduced shoot fresh and dry weights from as early as the first week of the hydroponic experiment. The 38/38 °C treatment also caused significant reduction in RGR and net assimilation rate during the first 2 weeks, but no significant differences were found during the last 2 weeks compared with 22/22 °C. Interesting responses were observed among genotypes in terms of shoot and root dry weights and root/shoot ratio at 38/38 °C treatment. The heat‐sensitive Siete Cerros showed the least reduction in these traits during the first 2 weeks while the heat‐tolerant Fang and Imam responded by greatly reducing their shoot and root weights. The situation was almost reversed with the duration of treatments such that Siete Cerros became the most affected genotype while Fang and Imam were better adapted to high shoot/root‐zone temperature. Specific root weight was the exceptional trait that increased under high temperature treatments. Results indicate that despite the reduction in root length and weight observed under high root‐zone temperature, shoot growth was not much affected suggesting that the use of suitable cultivar coupled with proper management could alleviate most of high root‐zone temperature effects during early growth stages. 相似文献
142.
Youhei Fukumori Seiji Osada Masami Nakajima Katsumi Akutsu 《Journal of General Plant Pathology》2009,75(3):188-190
To investigate maturation of spermatia of Botryotinia fuckeliana, we examined micro-structural changes in spermatia in liquid culture. Three to four spherical lipid bodies were seen in the
center of the cell at the start of culturing. After 3–7 days, maturing spermatia had developed large mitochondria along with
extensively developed granular endoplasmic reticulum. In contrast, the lipid bodies decreased not only in number but also
in size over time. The results obtained here suggest that the maturation of spermatia involves active cell metabolism using
the energy supply from lipid bodies. 相似文献
143.
The fading of flower color in bluish purple and reddish purple cultivars of Iris ensata and the in vitro stability of malvidin 3RGac5Gand petunidin 3RGac5G due to copigmentation with isovetixin under different pH conditions were
examined. The bluish purple cultivars exhibited higher flower color stability than the reddish purple cultivars 2 days after
anthesis. In the absence of isovitexin, malvidin 3RGac5G and petunidin 3RGac5G were not able to maintain color stability except
at low pH. However, the color stability of malvidin 3RGac5G and petunidin 3RGac5G was increased by copigmentation with isovitexin
under all pH conditions tested. Most remarkable was the stabilization of both anthocyanins due to the copigmentation at pH
4.2–6.2. Therefore, it can be concluded that the stability of flower color in the bluish purple cultivars of malvidin 3RGac5Gand
petunidin 3RGac5G type of I. ensata is caused at least in part by the copigmentation between these anthocyanins and isovitexin.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
144.
Yaguang Zhou Masami Fushitani Keiichi Sato Masayuki Ozawa 《Journal of Wood Science》2000,46(6):423-430
This study examined the bending creep behavior of hot-pressed wood during cyclic moisture changes. Sugi (Cryptomerica japonica D. Don) specimens were pressed in the radial direction under six combinations of nominal compressive strain (33% and 50%) and press temperatures (140°C, 170°C, 200°C). Creep tests were conducted at 20°C with three cyclic relative humidity changes between 65% and 95% under 25% of short-breaking stress. The effect of moisture content (MC) change on elastic compliance and mechanosorptive (MS) compliance was investigated. The relation between MS compliance and thickness swelling was studied. The results indicated that total compliance increased over the history of cyclic moisture changes; and its behavior was closely related to the changes in MC and thickness swelling. The total compliance increased during adsorption and decreased during desorption. Elastic compliance increased linearly with MC and was dependent on press temperature and compression. With increasing MC change, MS compliance increased during adsorption and decreased during desorption. The first adsorption led to greater MS compliance than did the subsequent adsorption with the same amount of MC change. In general, the elastic parameterK
E and the MS parameterK
Mincreased with compression and decreased as the press temperature increased. The MS parameterK
M was apparently greater than the elastic parameterK
E. The MS parameterK
M increased with swelling coefficient KSW of the hot-pressed specimen during adsorption and decreased with an increasing shrinkage coefficientK
SH during desorption. 相似文献
145.
146.
Effect of increased feeding of dietary α‐linolenic acid by grazing on formation of the cis9,trans11–18:2 isoform of conjugated linoleic acid in bovine milk 下载免费PDF全文
Mio Yamaguchi Taki Naito Yoshikazu Nagao Yukihito Kabuyama Kei Hashimoto Norihiro Azuma Isamu Maeda 《Animal Science Journal》2017,88(7):1006-1011
Feeding systems such as grazing affect the fatty acid profile of bovine milk fat. In addition, milk fat is formed as the product of fatty acid metabolism in cow bodies before being secreted into milk. However, how grazing influences milk fatty acid profile through the metabolism has not been completely characterized. When fatty acid concentrations in Holstein milk were compared between grazing and non‐grazing periods, α‐linolenic acid was significantly higher in the grazing period than in the non‐grazing period. This could be explained with an increase in α‐linolenic acid feeding with grazing. α‐linolenic acid had a linear positive correlation with conjugated linoleic acid (9c,11t‐18:2) (CLA) and vaccenic acid (VA) during the grazing period, whereas CLA had higher correlation with linoleic acid rather than with α‐linolenic acid during the non‐grazing period. These data indicate that the high content of dietary α‐linolenic acid affects CLA and VA formation in milk of grazing periods via α‐linolenic acid metabolism into VA. 相似文献
147.
Immunohistochemical analysis of c-yes and c-erbB-2 oncogene products and p53 tumor suppressor protein in canine mammary tumors 总被引:4,自引:0,他引:4
Rungsipipat A Tateyama S Yamaguchi R Uchida K Miyoshi N Hayashi T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(1):27-32
In order to evaluate the involvement of c-yes and c-erbB-2 oncogene products, and p53 tumor suppressor protein in canine mammary neoplastic lesions, sections of archived paraffin-embedded samples of 79 mammary tumors were analyzed immunohistochemically using antibodies against human c-yes p62 and c-erbB-2 products and p53. These 79 tumors were divided into 2 groups: 32 benign (2 adenosis, 7 simple adenomas, 14 complex adenomas, and 9 benign mixed mammary tumors) and 47 malignant tumors (26 simple adenocarcinomas, 7 complex adenocarcinomas, 5 solid carcinomas, 2 sclerosing carcinomas, 6 malignant mixed mammary tumors, and 1 malignant myoepithelioma). As a result of immunostaining, 40.6% (13/32) of the benign tumors and 21.3% (10/47) of the malignant tumors expressed the c-Yes oncogene product, ErbB-2 expression was detected in 50% (16/32) of the benign tumors and in 19.1% (9/47) of the malignant tumors. P53 expression was detected in 16% (4/25) of the benign tumors and in 30.6% (11/36) of the malignant tumors. Co-expression of c-Yes and ErbB-2, ErbB-2 and p53, and all 3 products was detected in 6, 1 and 7 tumors, respectively. 相似文献
148.
149.
Antigenic analysis of feline and bovine Chlamydia psittaci with monoclonal antibodies. 总被引:1,自引:0,他引:1
H Matsuno H Fukushi T Yamaguchi K Hirai 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1991,53(2):173-179
Monoclonal antibodies were established for antigenic analysis of feline and bovine Chlamydia psittaci. The monoclonal antibodies recognized lipopolysaccharide (LPS), 56-64, 84 or 86 kDa antigens. At least 5 antibody-binding sites were detected on LPS with the monoclonal antibodies. The 56-64 kDa antigen was suggested to have both polypeptide and carbohydrate antibody binding sites. Immunoblotting analysis of cat and cattle sera indicated that the 56-64 kDa antigen is an important antigen in host immune response. The monoclonal antibodies are extremely useful tools to analyse the structure and function of chlamydial antigens. 相似文献
150.
Masami Mochizuki Hisashi Furukawa 《Comparative immunology, microbiology and infectious diseases》1989,12(4):139-146
From the reasons that canine coronavirus (CCV) grows more efficiently than feline coronavirus in a cell culture and they are mutually related in their antigenicities, an enzyme-linked immunosorbent assay (ELISA) using CCV-infected feline kidney (CRFK) cells as substrate antigens was developed for detection of anti-coronavirus antibodies in cats. It was indispensable for generating coronavirus-specific ELISA antibody activities that the sample was applied to the mock-infected, normal CRFK cells in parallel with the CCV-infected cells and then the optical density values given by the mock-infected cell antigen were subtracted from those given by the virus-infected cell antigen. On the basis of ELISA antibody titers obtained in sera from the cats experimentally infected with CCV and from the spontaneous feline infectious peritonitis (FIP) cases, the ELISA described in the present study was found to be applicable as a simple and easy serologic test which was able to detect anti-coronavirus antibodies as efficiently as the indirect immunofluorescence assay with homologous FIP virus. 相似文献