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The hormone combinations and dark culture of the callus induction for Cyclocarya paliurus (Batal.) Iljinskaja leaves were 相似文献
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以本研究室家蚕基因库保存遗传系统的幼虫斑纹为观察对象,发现暗色斑(P^M).黑缟斑(P^S).杲蚕(U)鹑斑(q).褐圆斑(L)均存在斑纹浓淡程度不同且表型稳定的多型系统。根据杂交后能够识别浓淡型性状分离,将暗色斑分成浓型(P^M3).中型(P^M2)和淡型(P^M1),黑缟斑分成浓型(P^S2).淡型(P^S1),杲蚕分成浓型(U^2)和淡型(U^1),鹑斑分成浓型(q^3).中型(q^2)和淡型(q^1),褐圆斑分成浓型(L^2)和淡型(L^1)。同种斑纹内浓淡型间相互杂交,整体上均表现为等位基因的遗传模式,相对的浓型对淡型为显性,即:P^M3>P^M2>P^M1,P^S2>PS1,U^2>U^1,q^3>q^2>q^1,L^2>L^1。 相似文献
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Etsuko KASUYA Shiro KUSHIBIKI Ken‐ichi YAYOU Koichi HODATE Mizuna OGINO Madoka SUTOH 《Animal Science Journal》2012,83(3):238-244
Growth hormone (GH) secretion regularity and the effects of lighting condition and GH‐releasing hormone (GHRH) on GH release were determined in steers. First, steers were kept under 12:12 L : D conditions (light: 06.00–18.00 hours). The animals were then subjected to a 1‐h advancement in lighting on/off conditions (05.00 and 17.00 hours, respectively). Blood was sampled for 24 h at 1‐h interval on the seventh day of each condition. Second, GHRH was injected intravenously (IV) at 12.00 and 00.00 hours under 12:12 L : D and blood was sampled at 15‐min interval for 4‐h (1 h before and 3 h after the injection). Plasma GH concentrations were measured by a radioimmunoassay. Periodicity of GH secretory profile was calculated by power spectrum analysis using the maximum entropy method. Plasma GH concentrations showed a characteristic pattern consisting of four distinct peaks. Mean periodicity of GH secretory profile was 5.7 h, and it was not altered by any change in lighting conditions. IV injection of GHRH increased GH secretion during the day and night. The increase in GH secretory volume after GHRH injection during the night was equal to that during the day. The present results suggest that GH secreted from the anterior pituitary have regularity in steers. 相似文献
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植物内生真菌是生活在健康的植物体内不引起寄主植物任何病害的一类微生物。内生真菌具有丰富的多样性,在与寄主植物协同进化的过程中,通过不同方式为寄主提供有利保护。人们在对内生真菌的研究利用中,可根据研究的需要寻找特殊的内生真菌来源,为生产和研究提供最具研究价值和使用价值的资源。 相似文献
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Stefano Ghignone Giacomo Tamietti Mariangela Girlanda 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(8):861-870
Rhizopycnis vagum is a recently described coelomycete known to belong to the complex of root rot pathogens contributing to vine decline of cucurbits in several parts of the world. However, the fungus has also been reported to infect tomato, and as an endophytic associate of mycorrhizal roots of wild, asymptomatic Pinus halepensis and Rosmarinus officinalis plants in Italy. To accelerate epidemiological and ecological investigations on this fungus, a PCR primer pair was developed. Primers Rv1-F and Rv1-R were designed, based on alignment of internal transcribed spacer (ITS) sequences (ITS1-5.8S-ITS2), which amplified a 396-bp fragment from all R. vagum isolates tested, including isolates pathogenic to melons and endophytic isolates from mycorrhizae. Specificity of the primer pair was verified both in silico (BLAST searches using each primer string as a query) and in PCR assays, where the primers failed to amplify DNA from any isolate of fungi taxonomically related to R. vagum (e.g. Massarina walkeri and Stagonospora spp.) and other vine decline and common soilborne pathogens (e.g. Monasporascus cannonballus, Acremonium cucurbitacearum, Fusarium spp. and Rhizoctonia solani). Under optimum conditions, detectable amplification of the specific sequence required 0.05 pg of target DNA. Amplification of the expected 369-bp fragment was also obtained from DNA root extracts of nearly asymptomatic Cucumis melo plants inoculated with R. vagum under greenhouse conditions. 相似文献