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21.
利用管氏肿腿蜂防治红腹柄天牛幼虫   总被引:4,自引:1,他引:4  
利用管氏肿腿蜂防治红腹柄天牛幼虫的室内试验表明,在温度25-28℃,相对湿度为60%-70%,接蜂量按1∶3的虫蜂比,比较合适,出蜂率可达70%以上。  相似文献   
22.
Three ectomycorrhizal (ECM) isolates of Rhizopogon luteolus, R. roseolus and Scleroderma citrinum were found to differ markedly in their in vitro tolerance to adverse conditions limiting fungal growth, i.e. water availability, pH and heavy metal pollution. S. citrinum was the most sensitive, R. luteolus intermediate and R. roseolus the most tolerant species. Pinus radiata D. Don seedlings were inoculated in the laboratory and in a containerised seedling nursery with spore suspensions of the three ECM species. Colonisation percentage was considerably lower under nursery conditions, probably due to competition by native fungi. The effects of nursery ECM inoculation on seedling growth depended on the fungal species. Only R. roseolus-colonised plants showed a significantly higher shoot growth than non-mycorrhizal plants. All three fungi induced significantly higher root dry weights relative to control plants. Despite the low mycorrhizal colonisation, mycorrhization with all three species improved the physiological status of nursery-grown seedlings, e.g. enhanced root enzyme activity, shoot nutrient and pigment content, net photosynthesis rate and water use efficiency. Of the three fungal species, R. roseolus was the most effective; this species was also the most adaptable and showed the greatest range of tolerance to adverse environmental conditions in pure culture. It is, therefore, proposed as a promising fungal species for ECM inoculation of P. radiata in the nursery.  相似文献   
23.
Summary A greenhouse study was conducted to evaluate the effect of ectomycorrhizae on loblolly pine (Pinus taeda L.) growing in a Piedmont soil. Pine seedlings were inoculated with one of four species of fungi (Scleroderma aurantium, Pisolithus tinctorius, Thelophora terrestris, andRhizopogon roseolus). The seedlings were grown in pots containing a Cecil sandy clay loam amended to create a gradient of extractable P ranging from 5.9 to 52.5 g/g. After ten months, all colonized seedlings were significantly larger than control seedlings. However, of the four fungi,Scleroderma aurantium mediated a far superior shoot growth response to increasing levels of soil P; the seedlings were significantly larger than those colonized by any other fungus and also had the largest root systems and greatest degree of mycorrhizal colonization.  相似文献   
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桔青霉诱导子对红豆杉培养细胞中紫杉醇生物合成的影响   总被引:14,自引:0,他引:14  
在红豆杉培养红胞中,桔青霉诱导子促进紫杉醇的合成。将培养6-7d的桔青霉菌丝体的粗提物,以50μg碳水化合物/ml培养液的浓度加入到处于指数生长期末期的红豆杉培养细胞中,诱导子促进紫杉醇合成的作用最大。高压灭菌处理20-90min,不影响诱导子的活性。  相似文献   
27.
摘要 目的:探讨自体骨髓单个核细胞(bone marrow mononuclear cells,BM-MNC)植入治疗血管生成对硬皮病严重肢体缺血的影响。方法:收集我院2018年6月-2021年1月收治的腔隙性脑梗死(cerebral lacunar infarction,CLI)伴系统性硬皮病患者(systemic sclerosis,SSc)患者60例,根据患者治疗意愿区分为研究组(接受BM-MNC治疗,30例)与对照组(接受常规保守治疗,30例),对比两组患者干预后疼痛度、跛行距离、踝肱指数(ankle brachial index,ABI)、经皮氧分压以及不良反应的发生情况。结果:治疗前两组患者的VAS评分、跛行距离组间差异无统计学意义(P>0.05),治疗1个月时两组患者的VAS评分均较治疗前均降低,跛行距离均延长,组间差异明显(P<0.05),治疗6个月时比较显示研究组VAS评分明显低于对照组,跛行距离明显高于对照组(P<0.05)。治疗前两组患者的ABI、经皮氧分压差异无统计学意义(P>0.05),治疗1个月时两组患者的ABI、经皮氧分压均较治疗前升高(P<0.05),组间差异明显(P<0.05),治疗6个月时比较显示研究组ABI和经皮氧分压明显高于对照组(P<0.05)。研究组治疗6个月期间出现中风1例,肝肾功异常2例,不良反应总发生率为6.00 %,对照组治疗6个月期间出现非致命性心肌梗死1例,中风1例,肝肾功能异常3例,不良反应总发生率10.00 %,两组间不良反应发生率比较差异无统计学意义(P>0.05)。结论:对CLI伴发SSc患者实施自体骨髓衍生单核细胞植入治疗可行性较好,能够显著改善患者的肢体功能及患肢血运,同时治疗安全性较高,值得临床推广应用。  相似文献   
28.
A polyethylene terephthalate (PET) model substrate, bis-(benzoyloxyethyl)terephthalate (3PET), was used to screen for micro-organisms producing enzymes hydrolyzing PET. From this screen, a strain growing on 3PET was isolated and identified as Penicillium citrinum. The polyesterase responsible for 3PET and PET hydrolysis was purified to electrophoretic homogeneity. The polyesterase had a molecular weight of 14.1 kDa, and the Km and Kcat values on 4-nitrophenyl butyrate were 0.57 mM and 0.21 s-1, respectively. Highest enzyme activities were obtained when P. citrinum was grown on a medium containing cutin, which was hydrolyzed by the polyesterase. Surface hydrolysis of PET with the enzyme lead to an increase in hydrophilicity based on rising height (+5.1 cm) and drop dissipation measurements (55 s). Both from PET and 3PET bis-(2-hydroxyethyl)terephthalate and mono-(2-hydroxyethyl)terephthalate were released, while only low amounts of terephthalic acid were liberated.  相似文献   
29.
Two aminopeptidases, I and II, were found in the acidic fraction of the yeast autolysate, adsorbed on DEAE-cellose and DEAE-Sephadex A&50. Aminopeptidase I was purified as a single protein with a molecular weight of 200,000. The enzyme required Zn for its activity and hydrolyzed dipeptides, and a polypeptide (glucagon). It also hydrolyzed amides, naphthylamides and the p-nitroanilide of amino acids. The enzyme was strongly inhibited by sulfhydryl reagents. Aminopeptidase II seemed also to be a metal enzyme with a molecular weight of 34,000. The enzyme hydrolyzed the dipeptide and tetrapeptide but not leucine-p-nitroanilide.  相似文献   
30.
 Container-grown Pseudotsuga menziesii and Pinus pinaster seedlings were inoculated with water suspensions of spores of five ectomycorrhizal fungi commonly found in northeastern Spain. Pseudotsuga menziesii seedlings were inoculated with basidiospores of Melanogaster ambiguus, or Rhizopogon subareolatus, or with ascospores of Tuber maculatum. Pinus pinaster seedlings were inoculated with basidiospores of Melanogaster ambiguus, Rhizopogon roseolus or Scleroderma citrinum. The spore concentrations were 102–107 spores per seedling for Melanogaster ambiguus (in Pseu dotsuga menziesii) and Rhizopogon subareolatus, 103–107 for Melanogaster ambiguus (in Pinus pinaster), Rhizopogon roseolus, and Scleroderma citrinum, and 102–104 for Tuber maculatum. Melanogaster ambiguus colonized more short roots in a larger proportion of plants at 107 spores per seedling than at any other rate. The highest colonization by Rhizopogon subareolatus was obtained at 104 spores per seedling and higher, and all inoculated plants became infected at 106 spores per seedling and higher. Tuber maculatum colonized a high percentage of short roots at all rates tested; the proportion of infected plants was over 80% at 103–104 spores per plant, decreasing to 50% at 102 spores per plant. Rhizopogon roseolus colonized the highest number of short roots on nearly all the inoculated plants when applied at 105 spores per seedling and higher. Scleroderma citrinum colonized a high percentage of short roots on all inoculated plants when applied at 105 spores per seedling and higher. The abundance of sporocarps of Melanogaster ambiguus, Rhizopogon subareolatus, R hizopogon roseolus and Scleroderma citrinum and their colonization ability at relatively low rates allows these spores to be used as ectomycorrhizal inocula on a large scale. Accepted: 27 February 1996  相似文献   
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