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71.
Akari Fukuda Yoshihisa Okada Nobuo Suzui Toru Fujiwara Tadakatsu Yoneyama Hiroaki Hayashi 《Soil Science and Plant Nutrition》2013,59(8):1255-1262
The N-terminal amino-acid sequence of a major rice phloem-sap protein, designated as RPP23, was determined. The complete amino-acid sequence of RPP23 was deduced from the corresponding rice EST- clone and contained an extra 46 amino acids at the N-terminus, that was apparently cleaved off to form mature RPP23 in sieve tubes. RPP23 shared a similarity to plant small heat-shock proteins (smHSPs), though the N-terminal region of RPP23 was distinct from that of known smHSPs. Immunocytological analyses using leaf sections showed that RPP23 was located only in the phloem regions of leaves, and was present in non-stressed plants. In mature leaves, stronger immunocytological signals were detected in sieve elements than in companion cells. 相似文献
72.
AbstractPotherb mustard (Brassica rapa var. nipposinica) and tomato plants (scion, ‘CF Momotaro haruka’; rootstock, ‘Dokutar K’; Solanum lycopersicum) were cultured in hydroponic medium containing cesium-137 (137Cs) at three different concentrations (0.03, 0.13 and 1.03 Bq L?1), and uptake of 137C into the plants was determined. When the 137Cs radioactivity concentration in the medium was 1.03 Bq L?1, the 137Cs radioactivity concentrations in the edible portions of the plants were 4.80 Bq kg?1 fresh weight for the potherb mustard plants and 3.60 Bq kg?1 fresh weight for the tomato plants. In both species, the 137Cs radioactivity concentration in the edible portions decreased with decreasing 137Cs radioactivity concentration in the culture medium. When the 137Cs radioactivity concentration in the medium was 0.03 Bq L?1, a concentration observed in many streams and in tap water in Fukushima Prefecture after the accident at the Fukushima Daiichi Nuclear Power Plant, the 137Cs radioactivity concentrations in the edible portions of the plants were 0.50 and 0.15 Bq kg?1 fresh weight for potherb mustard and tomato plants, respectively. These values are less than the Japanese allowable limit for radiocesium in food. For both species, the transfer factors for 137Cs uptake from the culture media to the edible portions and the average transfer rates over the cultivation period were calculated. 相似文献
73.
A.K.M. Zakir Hossain M. Alamgir Hossain Hiroyuki Koyama Tetsuo Hara 《Soil Science and Plant Nutrition》2013,59(2):189-199
Aluminum toxicity and boron deficiency are the major factors that limit plant growth and development in acid soils and in B-deficient soils. Root growth inhibition is an early symptom of AI toxicity and B deficiency. Effects of AI and B supply and their interaction on the growth of wheat (Triticum aestivum L.) seedlings were investigated using hydroponics. Fifteen wheat cultivars commonly grown in Bangladesh were used and found to differ considerably in their tolerance to AI toxicity and B deficiency. The relative root length of all the wheat cultivars at 50 µM AI (pH 4.5) ranged from 27 to 71% relative to the control (0 µM AI). Among the cultivars, Inia66 and Kalyansona were found to be the most Al-tolerant and sensitive cultivars, respectively, based on the data of relative root length, malate exudation and AI content of roots. Malate was detected in all the cultivars in the presence of 100 µM AI (pH 4.3). Inia66 exuded a 6-fold larger amount of malate and the AI content of roots was 4 times lower than that in Kalyansona. The vigorous seedling growth was observed at 40 µM B among the series of B treatments. Considerable cultivar differences in response to 40 µM B were observed among the 15 cultivars. Kalyansona was considered to be the most sensitive and Kheri the most tolerant to B deficiency. The interaction effects of B ( 40 and 200 µM) and AI (50 µM) on seedling growth were also examined in Inia66 and Kalyansona. Root growth was inhibited in the presence of Al but B supply especially at 200 µM B in the Kalyansona cultivar caused a slight improvement. 相似文献
74.
Md. Taiabur Rahman Kazunobu Kawamura Hiroyuki Koyama Tetsuo Hara 《Soil Science and Plant Nutrition》2013,59(3):423-431
Effects of Al (0–100 μM) and Si (0–2,000 μM) supplied singly or in combination on root growth of different rice varieties were examined under hydroponic conditions. Al addition inhibited root elongation of rice plants, and the inhibition increased with increasing amount of Al in the culture solution. Among 22 indica varieties and among 8 japonica varieties tested, IAC3 and Nakateshinsenbon were relatively tolerant to AI, respectively, whereas IR45 and Norinl were relatively sensitive to AI, respectively. Si exerted a beneficial effect at all levels of Si treatment on indica varieties, whereas Si supply resulted in a slight increase in the root dry weight of japonica varieties only at the highest level (2,000 μM Silo The alleviation of Al inhibition of rice root growth by Si was observed in the combination of Al and Si treatments. Alleviation was more pronounced for all the Si treatments in indica varieties than in japonica varieties, and the alleviation was maximum with 2,000 μM Si in IR45. The alleviation effect by Si was more pronounced in the AI-sensitive varieties than in the AI-tolerant varieties. The application of Si resulted in an increase in the contents of Al and Si in plants, and there was no relationship between the Al content and Al inhibition in plants. 相似文献
75.
Eitaro Fukatsu Yoko Fukuda Makoto Takahashi Ryogo Nakada 《Journal of Wood Science》2008,54(3):247-251
Variations in carbon content in wood among 102 clones, selected from almost the entire natural distribution area, were investigated
in Larix kaempferi. The average carbon content was 50.50%, 50.94%, and 50.80% in sapwood, heartwood, and whole wood, respectively. The difference
in carbon content between clones was significant. The clonal repeatabilities were 0.46, 0.38, and 0.44 in heartwood, sapwood
and whole wood, respectively. The coefficients of variation in the clonal mean carbon content were only 0.43%, 0.42%, and
0.41% in heartwood, sapwood, and whole wood, respectively. This small genetic variation and resulting small relative genetic
gain of carbon content indicate that the genetic improvement of carbon content by selection has a small effect on the genetic
improvement of carbon sequestration capacity by selection in L. kaempferi. 相似文献
76.
Ban Masatoshi Hida Kazuhiro Kuwaki Motoyasu Horanai Tetsuo Ohnuki Tsutomu Oseko Norihisa 《Fisheries Science》2023,89(1):31-40
Fisheries Science - Blue sac disease (BSD) in salmonids results in the abnormal accumulation of ascites fluid and can often lead to mass mortality. However, the symptoms and causes of BSD remain... 相似文献
77.
Fumio NAMIKI Kanji SHIMIZU Kyoko SATOH Tetsuo HIRABAYASHI Kazufumi NISHI Tsuruo KAYAMURA Takashi TSUGE 《Journal of General Plant Pathology》2000,66(1):12-17
In 1994, Fusarium wilt of melon cultivars which are resistant to races 0 and 2 of Fusarium oxysporum f. sp. melonis was observed in southern area of the Lake Biwa region, Shiga prefecture. In commercial fields, mature plants of cv. Amus
which were grafted onto cv. Enken Daigi 2, and of cv. FR Amus showed yellowing, wilting and finally death before harvesting
of fruits. Diseased plants had vascular and root discolorations, and their stem sections yielded typical colonies of F. oxysporum. When the Shiga strains were tested for their pathogenicity to 12 species of cucurbits, they caused wilts only on melon.
Using race differential cultivars of melon, the Shiga strains were classified as race 1 of F. oxysporum f. sp. melonis, which has not been reported in Japan. To further characterize their pathogenicity, the strains were used to inoculate 46
additional cultivars of melon, oriental melon and oriental pickling melon. All the race 1 strains were pathogenic to the cultivars
tested, and their host range was apparently different from those of strains belonging to other races (races 0, 2 and 1,2y).
DNA fingerprinting with a repetitive DNA sequence, FOLR3, differentiated race 1 strains from strains of races 0 and 2, but
not from race 1,2y strains.
Received 2 July 1999/ Accepted in revised form 30 September 1999 相似文献
78.
Identification of RFLP markers linked with heading date and its heterosis in hexaploid wheat 总被引:3,自引:0,他引:3
Recombinant inbred lines (RILs) from a cross between hexaploid wheat (T. aestivum cv. Chinese Spring (CS) and T. spelta (Sp)) were used for RFLP analysis of heading date and heterosis. Fourteen RFLP markers linking with heading date were identified;
two were localized on chromosome 1A, one on 2A, three on 2B, one on 2D, four on 5A, two on 7A and one unlinked but reported
to be on group 2. All of these markers may be attributable to genes for earliness per se. However, the markers in the chromosomes of 1A and 7A are new to this study. RILs were crossed with (tim)-CS, the alloplasmic CS with T. timopheevi cytoplasm, and the heterosis from earlier-parent and mid-parents were calculated for the F1s to examine the heterotic effect toward earliness on heading date. Five and two RFLP markers were associated with heterosis
from the earlier-parent and mid-parents, respectively. They were distributed on the chromosomes of homoeologous groups 1 and
2.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
79.
The distribution of cortical resin canals and periderm formation in the cortex of Pinus thunbergii was studied in relation to early invasion of the pinewood nematode, Bursaphelenchus xylophilus. Nematode invasion was restricted in stem cuttings of P. thunbergii in which periderm closed cortical resin canals. Early invasion of the nematodes was also restricted in stem cuttings where wound periderm had formed in response to prior nematode inoculation. It was concluded that early invasion of pinewood nematodes in living bark tissue is restricted by periderm in mature stems and by wound periderm that had formed as the result of previous nematode infection. 相似文献
80.
Manabu Fukuda Kohji Takahashi Chiharu Ohkawa Yuya Sasaki Yasushi Hasegawa 《Fisheries Science》2013,79(6):1017-1025
In this study, we showed that feeding rats the organic extract of scallop shells (scallop shell extract) caused a decrease in the weights of white adipose tissues in rats fed a high-fat diet. In addition, the cholesterol concentration in the serum of rats that received a diet containing scallop shell extract was significantly lower than that in the serum of rats on the control diet. Feeding this scallop shell extract to rats increased the fecal weight as well as the fecal excretion of bile acids. The amino acid composition of the feces from rats fed the scallop shell extract was different from that of feces from rats fed the control diet, and treatment of the extract with pepsin and pancreatin identified a protein with a molecular weight of 90 kDa (90-kDa protein) as one of the indigestible proteins. Interestingly the 90-kDa protein was found to be identical to a free radical-scavenging protein we previously identified and showed the ability to bind bile acids. These results suggest that indigestible proteins (resistant proteins) in the scallop shell extract, including the 90-kDa protein, inhibit the absorption of bile acid by binding to it and cause increased excretion of fecal bile acid, which subsequently may decrease the serum cholesterol level. 相似文献