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排序方式: 共有115条查询结果,搜索用时 15 毫秒
1.
Toshihiko Karasawa Yoshiaki Kasahara Masako Takebe 《Biology and Fertility of Soils》2001,33(4):286-293
The effects of the preceding crops, sunflower (mycorrhizal host) and mustard (nonhost), on arbuscular mycorrhizal (AM) colonization and growth of succeeding maize were examined in 17 soils in an attempt to clarify the influence of soil characteristics on the effects of preceding crops. Shoot weight and P uptake of maize planted after sunflower were much higher than those after mustard in 14 soils, although the preceding crop had little effect on soil-P availability. AM colonization of maize after sunflower was much higher than that after mustard. The effect of the preceding crop was eliminated by soil sterilization. These results suggested that the differences in maize growth were caused by differences in the AM colonization. Correlation analysis of the effect of the preceding crop and soil properties showed that the difference in the effects on maize growth could not be explained by soil chemical properties, but only by the AM colonization of the preceding sunflower crop. In one of the 17 soils, however, the effect was not evident despite the higher AM colonization of sunflower. This soil was sterilized, and the effect of inoculation by AM fungi (AMF) on maize was examined. However, it was found that the inoculation increased AM colonization but did not improve maize growth at any P level, suggesting that the effect of AMF was unusually inhibited in this soil by unknown soil physicochemical properties. In most soils, however, the preceding mycorrhizal host crop, sunflower, improved the growth and AM colonization of maize depending on the AM colonization of sunflower. 相似文献
2.
Hatsugai N Kuroyanagi M Yamada K Meshi T Tsuda S Kondo M Nishimura M Hara-Nishimura I 《Science (New York, N.Y.)》2004,305(5685):855-858
Programmed cell death (PCD) in animals depends on caspase protease activity. Plants also exhibit PCD, for example as a response to pathogens, although a plant caspase remains elusive. Here we show that vacuolar processing enzyme (VPE) is a protease essential for a virus-induced hypersensitive response that involves PCD. VPE deficiency prevented virus-induced hypersensitive cell death in tobacco plants. VPE is structurally unrelated to caspases, although VPE has a caspase-1 activity. Thus, plants have evolved a regulated cellular suicide strategy that, unlike PCD of animals, is mediated by VPE and the cellular vacuole. 相似文献
3.
Chick embryos at 3 to 15 days of incubation were examined for the developmet and differentiation of the "four rings" of the heart. It was clarified that nodes and bundles of the impulse conducting system in the adult chicken were derived from these rings. This finding was very important for understanding the cardiac conducting system in birds and mammals. 相似文献
4.
Sawada Y Yanai T Nakagawa H Tsukamoto Y Tamagawa Y Yokoi S Yanagi M Toya T Sugizaki H Kato Y Shirakura H Watanabe T Yajima Y Kodama S Masui A 《Pest management science》2003,59(1):49-57
Nineteen analogues were synthesized by modifying the tert-butylhydrazine moieties of N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methyl-2,3-dihydro-1,4-benzodioxine-6-carbohydrazide and N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methylchromane-6-carbohydrazide (chromafenozide), and the synthesized analogues were evaluated for their insecticidal activity against Spodoptera litura F. While all of the synthesized analogues had insecticidal activity inferior to those of the lead compounds, several of the analogues nonetheless showed high insecticidal activity. Chromafenozide has shown very high selectivity toward lepidopteran species. 相似文献
5.
Optimal application timing of simeconazole granules for control of rice kernel smut and false smut 总被引:1,自引:0,他引:1
Mikio Tsuda Masashi Sasahara Toshiaki Ohara Shigehiro Kato 《Journal of General Plant Pathology》2006,72(5):301-304
We investigated the optimal timing of simeconazole (RS-2-(4-fluorophenyl)-1-(1H-1,2,4-triazol-1-yl)-3-trimethylsilylpropan-2-ol) application for controlling rice kernel smut in field trials in Miyagi Prefecture,
Japan, using formulations of simeconazole (1.5% granules). The field tests revealed that a submerged application of simeconazole
granules (450–600 g ai/ha) at 1–5 weeks before heading was highly effective against kernel smut, with treatments 1–2 weeks
before heading being the most effective. Submerged application of the fungicide at 2–5 weeks before heading was also highly
effective against false smut, with treatment 3 weeks before heading being the most effective. These periods overlap the timing
for optimal application of simeconazole to control rice sheath blight and ear blight. Consequently, we concluded that treatment
with simeconazole 2–3 weeks before heading can be a useful tool for controlling all four diseases. 相似文献
6.
7.
LIZhao-hua MikioKOBAYASHI 《林业研究》2004,15(3):233-242
In the past, utilization of bamboo resources in China has been traditionally dominated by direct consumption of local farmers as minor forest products with weak linkage with market. In recent years, the over-supply of grains and rapid degradation of agricultural environment call for alternative crops that can be developed through integrating the environmental plantation with the market demands. Closely associated with forestry and agriculture, bamboo is able to deal with the new challenges which China‘s agriculture is facing. Of 534 documented bamboo species in China, 153 species produce edibleshoots and of which 56 species are recommended for agricultural plantation; 139 species provide timbers and of which 58 species recommended; 116 species can be splited as good strips for weaving and of which 22 species recommended; 88 species are considered as garden bamboos and of which 34 species recommended; 45 species are able to produce paper pulp and of which 18 species recommended. 相似文献
8.
Tomoya Okunishi Naohiro Takaku Patcharawadee Wattanawikkit Norikazu Sakakibara Shiro Suzuki Fukumi Sakai Toshiaki Umezawa Mikio Shimada 《Journal of Wood Science》2002,48(3):237-241
Lignan production in callus and cell suspension cultures ofDaphne odora is reported for the first time. The cell suspension culture produced pinoresinol, lariciresinol, secoisolariciresinol, matairesinol, and wikstromol. The production of matairesinol in the cell suspension culture was much higher than that inDaphne odora stem tissues.Part of this report was presented at the 51th annual meeting of the Japan Wood Research Society, Tokyo, April 2001 相似文献
9.
Naohiro Takaku Keigo Mikame Tomoya Okunishi Shiro Suzuki Toshiaki Umezawa Mikio Shimada 《Journal of Wood Science》2001,47(6):493-496
A new lignan isoactifolin was isolated from young shoots (with leaves) ofChamaecyparis obtusa cv. Breviramea. The structure of the compound was determined based on spectroscopic evidence.Parts of this report were presented at the 44th lignin symposium, Gifu, October 1999 相似文献
10.
Tomoya?Okunishi Norikazu?Sakakibara Shiro?Suzuki Toshiaki?UmezawaEmail author Mikio?Shimada 《Journal of Wood Science》2004,50(1):77-81
Secoisolariciresinol dehydrogenase activity was detected for the first time from Daphne odora and Daphne genkwa (Thymelaeaceae), which are known to produce optically pure (+)-matairesinol. In sharp contrast, (–)-matairesinol was formed selectively over the (+)-antipode by the secoisolariciresinol dehydrogenase preparation from both D. odora callus and D. genkwa shoots. 相似文献