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961.
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以北京市怀柔区宝山镇野生墨汁鬼伞(Coprinus atramentarius)为试验材料,对其母种、原种培养基配方进行优化筛选,并采用不同栽培方式研究了野生墨汁鬼伞人工驯化的培养条件。结果表明:实验范围内供试菌株的菌丝体生长最适碳源为葡萄糖+玉米淀粉,最适氮源是蛋白胨,最适pH值为9。培养料配方以棉籽壳、麸皮、玉米粉、石灰、锯末、石膏的配方最好,出菇以菌棒立栽覆土效果最好,覆土后55d现菇蕾,3~5d可采收。第一潮出菇生物学效率可达40%左右,条件适宜可出3~4潮菇。 相似文献
963.
通过对林业院校特点的分析,阐述了其开设《汽车文化》公共选修课的意义。结合近几年的教学实践,介绍了《汽车文化》公共选修课程的教学内容和安排,以推动该课程在林业院校的教学建设与改革。 相似文献
964.
Low‐pathogenicity avian influenza (LPAI) viruses have caused illness in poultry and humans with poultry contact. To determine whether there is evidence of exposure to avian influenza viruses (AIV) among backyard poultry in Minnesota and their human caretakers, 150 flocks of backyard birds were sampled for antibodies to AIV from August 2007 through December 2008. One hundred flocks were tested through routine slaughter surveillance by the Minnesota Board of Animal Health and an additional 50 flocks were contacted and sampled by study investigators. Blood was collected from 10 to 13 birds from each flock and a survey of biosecurity and management practices was administered to the flock owner. Blood samples were tested by agar gel immunodiffusion (AGID) for influenza A antibodies. Tested flocks had a median flock size of 100 birds (range: 12–800 birds), and were most commonly owned for meat for personal use (81% of respondents), fun or hobby (58%) and eggs for personal use (56%). Although 7% of flock owners reported that their birds had shown respiratory signs in the previous 3 months, only 1 of 150 flocks tested positive for influenza by AGID. Antibodies to LPAI H6N1 were detected in the positive flock. The owner of the positive flock did not have antibodies to H6 or other common AIV. Based on the findings of this study, the risk of transmission of LPAI viruses from backyard poultry to owners in Minnesota appears to be low under current conditions and management practices. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1-4):165-175
Bacteria inhabiting the xylem of Norway spruce (Picea abies (L.) H. Karsten) were investigated. The trees had been wounded and artificially inoculated with fungi and bacteria obtained from wounds of naturally infected spruce. One and five growing seasons after inoculation the Gram‐negative bacterial population present in the stem of inoculated trees were analysed. The Gram‐negative bacteria isolated from the trees were identified on the basis of morphological, biochemical and physiological tests and whole‐cell fatty acid composition. The predominant strains were Enterobacteriaceae fermenter strains (E. agglomerans or E. sakazakii), fluorescent and yellow pigmented Pseudomonas, Acinetobacter and Moraxella spp. All Gram‐positive bacteria were Bacillus species. The Gram‐negative bacteria of Norway spruce differed from the Gram‐positive species in possessing stronger lipolytic activity and in their ability to utilize pine resins for growth. Gram‐positive bacteria were generally able to utilise cellulose and hemicellulose, whereas among the Gram‐negative bacteria only one xylanolytic (yellow Pseudomonas) strain was found. 相似文献
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