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101.
许多不同的技术可以促进农业生产力的持续增长,生物技术是其中最重要和最有前途的方法。因为生物技术不仅可以增加生产力。而且在环境和自然资源的保护中起重要作用,应用生物技术可以生产高产、优质、高抗性和无病植物,同时也可以提高育种效率和促进食品的工业化生产。苏云金杆菌抗虫基因是目前生物技术领域中应用最广泛的例子之一。由此而产生的抗虫植物正在广泛应用于世界各地的商业化生产。本文综述了苏云金杆菌抗虫基因的研究进展和它在未来林木遗传工程中的应用。表4参68。 相似文献
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芽孢杆菌属细菌在芽孢状态下,对外界环境及理化因素具有高度抵抗力。适宜的温度、湿度及营养条件能促进芽孢萌发,影响其对常规灭菌方法的抵抗力。本试验选取蜡样芽孢杆菌作为研究对象,在适宜培养条件下使其形成芽孢,通过研究萌发后芽孢对温度、H2O2及含氯消毒剂等条件的抵抗力,证实了适当的条件(温度37 ℃、湿度40%、pH 7.4、30 min)能有效促进蜡样芽孢杆菌芽孢萌发,致使芽孢对高温(80 ℃、2 h)、H2O2(1.5 mol/L、2 h)及含氯消毒剂(有效氯含量约800 mg/L、2 h)等常规灭菌方法抵抗力明显降低,并能被有效杀灭和灭活,相对有效杀灭率分别达98.4%、98.9%及99.1%,有效杀灭率分别为88.3%、88.7%及88.9%,这对进一步研究芽孢杆菌属细菌的杀菌消毒条件具有重要参考意义。 相似文献
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M.C. HIDALGO A. SKALLI E. ABELLÁN M. ARIZCUN & G. CARDENETE 《Aquaculture Nutrition》2006,12(4):256-266
Two feeding trials were carried out to evaluate the efficiency of probiotics and maslinic acid, on growth and survival of juvenile dentex; liver proteolytic activities were also investigated in the second trial. For experiment 1, triplicate groups were fed six diets with two probiotics (Bacillus toyoi, T, and B. cereus, E) at increasing levels (0.5, 1 and 2 g kg?1 diet) and a control diet. Growth and feed conversion were not significantly influenced by the probiotics. The diet T1 produced the lower mortality, whereas diet E1 rendered the higher mortality. It was concluded that no significant effects on growth and survival were found following the addition of two kinds of probiotics to dentex diets. However, the diet E0.5 showed a tendency to ameliorate the growth and feed utilization of the diet. In a second trial, triplicate groups were fed four diets with increasing levels of maslinic acid (0, 20, 40 and 80 mg kg?1 diet). Growth of fish given diets with the highest level of maslinic acid (D80) was slightly but not significantly lower than those from the other groups. Furthemore, mortality of fish fed diet D40 was the lowest. Changes in liver proteasome and endoprotease activities measured on sodium dodecyl sulphate (SDS)/gelatin gels were also detected in a dose‐dependent manner. It was concluded that a dietary maslinic acid at a level of 80 mg kg?1 diet seems to be too high for juvenile dentex to maintain a maximal growth and survival rate. 相似文献
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The objective of this study was to evaluate of the growth performance, serum biochemical indices, liver antioxidant parameters and ability of anti-infection with Aeromonas hydrophila by adding the fermented Chinese medicine by Bacillus Subtilis to the carp fish feed, and to find out the appropriate supplemental level of fermented Chinese medicine in diets. Carp fingerling with an initial body weight of (35±0.5) g were set up to 6 experimental diets supplemented with 0 (control group), 0.1‰, 0.5‰, 1‰, 2‰ and 3‰ fermented Chinese medicine for 56 days, respectively. Each group had 30 fish and set up 3 repetitions. After the feeding trail,the fish were challenged with Aeromonas hydrophila to calculate the relative percentage survival (RPS).The results showed as follows:Supplementing fermented traditional Chinese medicine by Bacillus subtilis, the weight gain rate (WGR), specific growth rate (SGR), condition factor (CF), the activities of lysozyme (LSZ), complement 3 (C3),total protein (TP),total anti-oxidation capacity (T-AOC),total superoxide dismutase (T-SOD) and catalase (CAT) in serum of common carp were enhanced at different degrees, while the feed coefficient (FCR)and malondialdehyde (MDA) in serum were declined at different degrees.When the fermented Chinese medicine supplemental levels were 2‰ and 3‰,the effects were significant (P<0.05)(except for C3, ALP and Cr).The experimental results of the virulence of common carp infected with pathogen Aeromonas hydrophila showed that,the fermented herbal could obviously improve the ability of anti-infection, the immune protective rate of the group with 2‰, 3‰ doses of the fermented Chinese medicine could reach 77.23% and 74.63%, respectively. From what had been discussed above, the group with 2‰ and 3‰ doses of the fermented Chinese medicine had significant effect on the growth performance, serum biochemical indices, liver antioxidant parameters and Aeromonas hydrophila anti-infection ability. Considering the cost of adding fermented Chinese medicine, the recommendations for the best additive quantity was 2‰. 相似文献
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枯草芽孢杆菌CY1是一株广谱性的根际促生菌,为促进农业废弃物的资源化利用,提高固态发酵生产生物有机肥过程中枯草芽孢杆菌CY1的扩繁能力,研究采用猪粪堆肥为原料,麸皮、豆粕、玉米粉为辅料进行固态发酵研制新型生物有机肥,以有效活菌数为参考指标,确定原料、辅料最佳配比及接种量。选用Plackett-Burman试验设计对影响发酵的8个因素进行效应评价,筛选出具有显著效应的3个因素:初始pH、发酵温度及含水量。用最陡爬坡试验逼近最大响应区域,通过响应面分析法确定最优发酵工艺参数。结果表明,固态发酵条件为初始pH 7.51、KH2PO4含量0.75%、MgSO4含量0.15%、MnSO4含量0.15%、发酵温度36.10℃、葡萄糖含量6.00%、(NH4)2SO4含量0.75%、含水量26.33%,此时固态发酵产物有效活菌数最大,达到4.57×1010 CFU·g-1。该研究为利用农业废弃物采用合适的... 相似文献
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