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Seed coating with molybdenum compounds improves seedling establishment for rice, wheat, barley, and soybean when such seeds were sown under flooded conditions. Tungsten belongs to the same chemical group as molybdenum in the periodic table, and similar to molybdenum, inhibits the generation of sulfide ions. Here, the effects of tungsten and molybdenum containing seed coatings on seedling establishment under flooded conditions were compared using rice, wheat, barley, and soybean. In rice, the effects of tungsten compounds on seedling establishment varied. Tungsten trioxide had little effect but tungstic acid and ammonium phosphotungstate significantly improved seedling establishment when the amounts were at least .1–.2 mol W kg?1. Although the effect of tungsten coating varied depending on the compound used, ammonium phosphotungstate, along with other tungsten compounds, improved seedling establishment in a manner comparable with that of molybdenum compounds. For wheat and barley, ammonium phosphotungstate treatment resulted in a significant increase in establishment that was only slightly less than the results observed using molybdenum compounds. Tungstic acid and ammonium phosphotungstate treatments improved soybean establishment in a significant manner that was comparable with those of molybdenum compounds. Collectively, these results suggest that tungsten compounds, as well as molybdenum compounds, improve seedling establishment under flooded conditions.  相似文献   
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Alpha‐melanocyte stimulating hormone (α‐MSH) is one of the main regulators for melanocytes, and the adenohypophysis is one of the major tissues for the synthesis of this hormone. The Silky fowl is a characteristic breed of chicken with hyperpigmentation throughout the body. The involvement of the adenohypophysis in the hyperpigmentation of this breed is not known. In the present study, the proportion of melanocyte stimulating hormone‐immunopositive cells (MSH cells) in the adenohypophysis was immunocytochemically compared between Silky, Red Cornish × New Hampshire (RN) crossbred and Japanese bantam cockerels at 15 weeks of age. After the body and gland were weighed, the adenohypophyseal cells were enzymatically dispersed and immunostained for α‐MSH, and the immunopositive MSH cells were counted. The weights of the body and adenohypophysis were heaviest in the RN crossbred, followed by the Silky and lightest in the bantam cockerels. In contrast, the ratio between adenohypophysis and bodyweight was much larger in the Silky and the bantam than in the RN crossbreed (P < 0.05). The population of MSH cells in the adenohypophysis was larger in the Silky (14.3%) than in the RN crossbreed (8.0%) and the bantam (8.1%) cockerels (P < 0.05). From these results, it was concluded that prepubertal Silky cockerel have numerous MSH cells in the adenohypophysis suggesting a relationship to hyperpigmentation.  相似文献   
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Perchloric acid-soluble protein (PSP) is a members of a new hypothetical family (YER057c/YJGF family) of small proteins with presently unknown function. The high degree of evolutionary conservation of these proteins reflect an involvement in basic cellular regulation. The expression of PSP was examined in rat hepatoma cell dRLh 84-beared rats. The tumor weight increased to 4.24 g at 3 weeks after the transplantation of hepatoma cells and hepatoma which has less differentiated characteristics were observed in rat liver. The expression of PSP in rat hepatoma was down regulated as compared with intact tissue. Thus the expression of PSP seems to be associated with the differentiation process in these transformed cells. On the other hand, some positive cells against the PSP-antibody were observed in the central region of tumor tissue by immunohistochemistry. These cells were shown to be the lymphocytes and the macrophages. The involvement of PSP to cellular growth and differentiation is discussed.  相似文献   
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Daylily rust fungus, Puccinia hemerocallidis, was proven to host-alternate between a wild daylily, Hemerocallis fulva var. longituba, and a patrinia, Patrinia villosa. No proof was obtained for the early belief that the fungus is pathogenic to plantainlilies, Hosta species, in addition to daylilies, Hemerocallis species. The fungus seems to alternate regularly between daylilies and patrinias in Japan because most daylily species are deciduous, and a vegetatively reproducing stage of the pathogen does not seem capable of successfully overwintering free of the living host tissue.  相似文献   
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ABSTRACT Nematicidal activity of essential oils extracted from 27 spices and aromatic plants were evaluated in vitro and in pot experiments. Twelve of the twenty-seven essential oils immobilized more than 80% of juveniles of the root-knot nematode Meloidogyne javanica at a concentration of 1,000 mul/liter. At this concentration, most of these oils also inhibited nematode hatching. Essential oils of Carum carvi, Foeniculum vulgare, Mentha rotundifolia, and Mentha spicata showed the highest nematicidal activity among the in vitro tested oils. These oils and those from Origanum vulgare, O. syriacum, and Coridothymus capitatus mixed in sandy soil at concentrations of 100 and 200 mg/kg reduced the root galling of cucumber seedlings in pot experiments. The main components of these essential oils were tested for their nematicidal activity. Carvacrol, t-anethole, thymol, and (+)-carvone immobilized the juveniles and inhibited hatching at >125 mul/liter in vitro. Most of these components mixed in sandy soil at concentrations of 75 and 150 mg/kg reduced root galling of cucumber seedlings. In 3-liter pot experiments, nematicidal activity of the essential oils and their components was confirmed at 200 and 150 mg/kg, respectively. The results suggest that the essential oils and their main components may serve as nematicides.  相似文献   
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In tomato plants, α-tomatine, a steroidal glycoalkaloid saponin, inhibits fungal growth. Tomato pathogens that produce host-specific toxins, Alternaria alternata tomato pathotype causing Alternaria stem canker and Corynespora cassiicola causing Corynespora target spot, were investigated for sensitivity to α-tomatine. Although spore germination of A. alternata pathogenic and nonpathogenic to tomato and of C. cassiicola pathogenic to tomato was not affected by 0.1 mM α-tomatine, spore germination of C. cassiicola nonpathogenic to tomato was significantly inhibited. This result showed that A. alternata, regardless of its pathogenicity, and only the C. cassiicola pathogenic to tomato are resistant to α-tomatine. Germinating spores of A. alternata and C. cassiicola resistant to α-tomatine detoxified α-tomatine by degrading it to a less polar product. After inoculation of tomato leaves, spores of A. alternata and C. cassiicola nonpathogenic to tomato germinated and formed appressoria, but did not form infection hyphae in host tissues. When a host-specific toxin (CCT-toxin) produced by C. cassiicola pathogenic to tomato was added to nonpathogenic spores, colonization within leaves was observed in A. alternata, but not in C. cassiicola. On the other hand, when spores of C. cassiicola nonpathogenic to tomato were suspended in spore germination fluid of nonpathogenic A. alternata with α-tomatine detoxification activity, the fungus could be induced to colonize leaves in the presence of CCT-toxin. These results indicate that A. alternata tomato pathotype and C. cassiicola pathogenic to tomato detoxify α-tomatine during infection and that this detoxification is essential for host colonization by pathogens that produce host-specific toxins.  相似文献   
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To identify possible sites of viral attenuation, the complete nucleotide sequences of two isolates of Zucchini yellow mosaic virus (ZYMV) were determined; a severe isolate Z5-1 and an attenuated isolate from Z5-1 (designated ZYMV-2002). The viral genome of both isolates consisted of 9593 nucleotides in size and contained an open reading frame encoding a single polyprotein of 3080 amino acids. Comparison of the nucleotide sequences for Z5-1 and ZYMV-2002 revealed 14 nucleotide mutations, resulting in seven amino acid substitutions with four in the HC-Pro region, two in the CI region, and one in the NIb region. These results provide a genetic basis for future manipulation of the ZYMV reverse genetics system. The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession numbers AB188115 and AB188116  相似文献   
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