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排序方式: 共有866条查询结果,搜索用时 15 毫秒
861.
Incongruence between RFLPs of chloroplast DNA and morphological classification in east Asian pear (Pyrus spp.) 总被引:5,自引:0,他引:5
Hiroyuki Iketani Tohru Manabe Nagao Matsuta Tomoya Akihama Tateki Hayashi 《Genetic Resources and Crop Evolution》1998,45(6):533-539
Polymorphism of chloroplast DNA of 106 accessions of Pyrus (mainly east Asian accessions) was examined. Four haplotypes were observed with the combination of three independent restriction site mutations digested by EcoO109 I, Sal I, and Xba I, respectively. In the occidental pear accessions only the most plesiomorphic type was observed, whereas all four types appeared in the oriental pear accessions. This suggests that the oriental species of Pyrus and occidental ones may have evolved independently. The distribution of four haplotypes in the east Asian pear was quite incongruent with the species or infrageneric classification using mainly morphological characters. Considering the high crossability and much occurrence of suspected interspecific hybrids in wild populations, this disaccord is inferred to be the results of the hybridization and introgression between species. 相似文献
862.
Takeru Gonai Toru Manabe Eiichi Inoue Mikio Hayashi Toshiya Yamamoto Tateki Hayashi Fumio Sakuma Masakazu Kasumi 《Scientia Horticulturae》2006
Although there have been some attempts to obtain intergeneric hybrids between Japanese pear (Pyrus pyrifolia Nakai) and apple (Malus × domestica Borkh.) mature hybrids have not been generated due to hybrid lethality. Shoots from immature hybrid embryos were gamma irradiated and cultured at normal temperature conditions to obtain viable intergeneric plants. Gamma irradiation doses of 50 and 100 Gy cultured at 25 °C killed all shoots but there was one survivor at 150 Gy and 25 °C. Hybrid status of the shoot was confirmed by using morphology, flow cytometry and SSR markers. The intergeneric plant had similar leaf serrations to apple and similar petioles to Japanese pear. Flow cytometric analysis revealed that the intergeneric shoot had a DNA content intermediate between the parents. SSR analysis showed one allele from each parent for all 16 SSR loci investigated. These data strongly suggest that the obtained shoot is a true hybrid between Japanese pear and apple. 相似文献
863.
Shortage of organic matter hinders agricultural production in the Sahel, and this lack of enough organic matter is more severe for peri-urban horticulture, which depends heavily on it. Alternative sources of organic matter that offer new options for peri-urban horticulture can help reduce the potential for conflict over finite resources between traditional crop production and peri-urban horticulture. Both agronomic and economic evaluations of an organic amendment called heated sewage sludge (HSS) were conducted in the research station of International Crops Research Institute for the Semi-Arid Tropics (ICRISAT)-Niamey, Niger, West Africa. For this study, HSS, a material imported from Japan, applied at a dosage application equivalent to 20.0 kg 100 m−2 on lettuce fields led to production levels as high as those of conventional methods, and the yield became even higher than those of conventional methods when the dosage was increased to 50.0 kg 100 m−2 and 100.0 kg 100 m−2. Even though HSS was imported, its benefits outweighed its cost, as evidenced by the positive net returns. Since profitability in peri-urban horticulture is much higher than that of traditional crop production, the results of this study imply that if adopted, the use of HSS can lead to increased availability of organic matter for traditional cropping systems. 相似文献
864.
Megumi Matsumoto Kazuma Hayashi Kyosuke Araki Teruyuki Nakanishi Atsushi Yamamoto 《Journal of fish diseases》2020,43(1):81-89
Mycobacteriosis in cultured fish is a challenge for the aquaculture industry worldwide. Treatment by chemical administration is difficult and no effective vaccine has been developed. Therefore, detection and isolation by early diagnosis are important for prevention of the spread of the disease. In mammals, interferon gamma release assays have been established for detection of tuberculosis; these tests are based on the delayed-type hypersensitivity (DTH) response against culture filtrate protein-10 (CFP-10) and the 6-kDa early secreted antigen target (ESAT-6) of Mycobacterium tuberculosis. On the other hand, little is known about the fish immune response against the ESAT-6 and CFP-10 proteins of mycobacteria, although these responses should find application in the diagnosis of mycobacteriosis in fish. In the present study, we identified ESAT-6 and CFP-10 from Mycobacterium pseudoshottsii and cloned the corresponding genes. Intraperitoneal injection of the corresponding DNA plasmid constructs in ginbuna crucian carp yielded increased expression of the fish interferon-γ1-1-encoding gene (IFN-γ1-1). In contrast, IFN-γ1-1 expression accompanied by DTH response was observed only in the CFP-10-DNA plasmid-injected fish. Furthermore, fish that had been prophylactically injected with CFP-10-DNA plasmid exhibited increased survival of M. pseudoshottsii infection. Taken together, these results suggested that CFP-10 may facilitate diagnosis of mycobacteriosis. 相似文献
865.
Okamura Akihiro Yamada Yoshiaki Horie Noriyuki Mikawa Naomi Tsukamoto Katsumi 《Fisheries Science》2019,85(4):687-694
Fisheries Science - The efficiency of a new liquid-type diet for long-term rearing of Japanese eel larvae until metamorphosis was examined, as was the effect of diet viscosity on diet intake and on... 相似文献
866.
Polyclonal and monoclonal antibodies reactive with acifluorfen (AF) were prepared by the immunization of, respectively, rabbits and mice with AF-bovine serum albumin conjugates. The reactivities of polyclonal antibody and three monoclonal antibodies (AF 9-1, AF 51-5 and AF 75-144) were examined in an indirect competitive enzyme-linked immunosorbent assay (C-ELISA). The polyclonal antibody reacted with AF at concentrations of 1·5 to 800 μg litre-1, while the monoclonal antibodies reacted with AF at concentrations of 3 to 24 μg litre-1 for AF 9-1, 1·5 to 12 μg litre-1 for AF 51-5 and 12 to 48 μg litre-1 for AF 75-144. In the presence of up to 40% methanol in C-ELISA, the monoclonal antibodies, particularly AF 75-144, were less affected in their reactivities with AF than was the polyclonal antibody. Moreover AF 9-1 and AF 51-5 specifically reacted with acifluorfen-methyl and oxyfluorfen, while AF 75-144 reacted with chlornitrofen which did not react with the other antibodies. These results indicated that the antibodies are useful for the assay of AF and its related compounds. © 1997 SCI. 相似文献