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91.
[目的]该研究基于天然表面活性剂开发出了石蜡防水剂与铜唑(CA-B型)防腐剂的复配体系,考察了复配体系处理材的防霉防蓝变性能。[方法]采用0.3%和0.5%2种浓度的CA-B和0.5%、1.0%、2.0%3种浓度的石蜡乳液制备复配体系,利用满细胞法浸注处理50 mm(L)×20 mm×5 mm的南方松(Pinus spp.)试材,根据国标GB/T18261-2000针对蓝变菌可可球二孢(Botryodiplodia theobromae Pat.)和霉菌黑曲霉(Aspergillus niger V.Tiegh)、绿色木霉(Trichoderma viride Pers.ex Fr.)对复配处理材进行抗蓝变和抗霉变试验。[结果]石蜡乳液和CA-B均能改善木材的抗霉变和抗蓝变效果,但在一定范围内,石蜡乳液浓度增加对抗霉变和抗蓝变效果略有负面影响。[结论]以期促进木质生物质资源的高附加值利用,推动行业向更高效、更环保的方向发展。  相似文献   
92.
The association between blue stain fungi andIps cembrae Heer (Coleoptera: Scolytidae) was investigated in the Japanese larch,Larix leptolepis Gordon, in the Nagoya University Forest, Aichi Prefecture, central Japan.I. cembrae had one or two generation(s) in a year in this study area. Two blue stain fungi,Ophiostoma piceae andLeptographium sp., were isolated from the body surface of both male adults in mating chambers and female adults in parent galleries, suggesting that this beetle species was a vector of these fungi. Although no blue stain fungi were isolated from non-stained wood, both fungi were isolated from the mating chambers, the center and the uppermost end of the galleries throughout the season. The fact thatO. piceae was consistently isolated with high frequency from adults and from their galleries strongly suggested that this species would be the principal blue stain fungus infecting the beetle-attacked larch trees.  相似文献   
93.
引起橡胶和马尾松木材蓝变的真菌—可可球二孢   总被引:1,自引:0,他引:1       下载免费PDF全文
可可球二泡(Botryodiplodia theobromae Pat.)早在1879年就被Cooke发现,目前,至少拥有48个异名,常见的异名是Diplodia theobromae(Pat.)Nowell,Diplodia natalensis PoleEvans,Lasiodiplodia theobromae(Pat.)Griff.& Maubl。Punithalingam和Sutton分别对该菌作过详细的评述。它广泛分布于热带、亚热带和温带。其寄主植物已知约500种,它不但引起植物病害,而且还引起木材蓝变,是引起热带阔叶树木材蓝变的主要真菌之一。虽然国外对这种真菌已进行了大量研究,但国内研究尚少,由它引起的木材蓝变,国内尚未见报道。  相似文献   
94.
纵坑切梢小蠹蓝污真菌侵害云南松树组织解剖观察   总被引:1,自引:0,他引:1  
叶辉  吕军 《林业科学》2001,37(6):71-74
通过对云南松树进行纵坑切梢小蠹(Tomicus piniperda)蓝污真菌(Leptogramphium yunnanense)接种试验,对云南松受害组织进行了形态解剖观察,验证了蓝污真菌对云南松的致病作用。蓝污真菌发现于受害木质部和韧皮组织中的各类细胞中,在木质部,蓝污区域呈现出以心材为中心的扇形分布。在韧皮组织内,蓝污真菌主要沿着细胞轴向在垂直方向上生长,并可通过孔纹进入到水平方向上的相邻细胞内。本项研究揭示了该蓝污真菌在云南松树干韧皮和木质部组织,细胞内的生长和蔓延规律,进一步表明纵坑切梢小蠹蓝污真菌L.yunnanense是云南松的一种病原真菌。  相似文献   
95.
To confirm the pathogenicity of a blue stain fungus,Ceratocystis piceae (Münch) Bakshi to the Japanese red pine (Pinus densiflora Sieb. et Zucc.), the responses of healthy young pine trees and stressed trees which were girdled by the half-circumferential girdling technique were investigated by the fungal inoculation test. Although neither of the pine trees inoculated withC. piceae in the non-girdled treatment nor the controls died, mortality of the trees girdled and inoculated withC. piceae was 28.6%. In the pine trees inoculated withC. piceae, the mean area of the necrotic lesion of the sapwood was significantly larger than that of the controls, and the mean of the water pressure potential of the xylem decreased, regardless of the girdling treatment. TheC. piceae was reisolated from the wood pieces near the inoculation points on the inoculated trees, but not from the controls. These results suggest that under strongly stressed conditions, the Japanese red pine trees might have been killed by heavy infestations ofC. piceae carried by bark beetles. A part of this paper was presented at the 103rd Annual Meeting of the Japanese Forestry Society (1992).  相似文献   
96.
Fifty pole stage trees were inoculated with O. polonicum at monthly intervals between May and September. Most infection, measured as the area of sapwood blue‐stained, occurred in July and least in May and September. The difference between July, August and September might be explained by the effect of temperature on fungal growth, but in May and June the trees had a higher resistance than expected. Tree resistance was correlated with resinosis. Tree variables not correlated with resistance were DBH, annual ring width, periodic growth, vigor index, or phloem carbohydrate concentration.  相似文献   
97.
板栗是一种加工贮藏难度大的干果,因加工糊化而产生的褐变问题严重限制了板粟的开发利用.对极粟加工糊化中褐变的成因作了实验分析和理论上的探讨.结果表明,单宁与Fe3 氧化成色以及Maillard反应是引起栗果褐变的主要原因,并且温度、水分、pH值、氧化还原剂、糖分等对Maillard褐变有影响.并提出了板栗贮藏加工时的护色处理方法。  相似文献   
98.
To consider the optimal training programme for Thoroughbred horses, we examined the recruitment pattern of muscle fibres including hybrid muscle fibres in well-trained Thoroughbred horses. The horses performed exercise at three different intensities and durations; i.e., 100% VO2max for 4 min, 80% and 60% VO2max for 8 min on a treadmill with 10% incline. Muscle samples were obtained from the middle gluteal muscle before, during (4 min at 80% and 60% VO2max), and after exercise. Four muscle fibre types (types I, IIA, IIA/IIX, and IIX) were immunohistochemically identified, and optical density of periodic acid Schiff staining (OD-PAS) in each fibre type, and the glycogen content of the muscle sample, were determined by quantitative histochemical and biochemical procedures. The changes in OD-PAS showed that the recruitment of all fibre types were identical at the final time stage of each exercise bout, i.e., 4 min running at 100% VO2max, and 8 min running at 80% and 60% VO2max. The changes in OD-PAS of type IIA/IIX fibre were very similar to those of type IIX fibre. The recruitment of these fibres were obviously more facilitated by 4 min running at 100% VO2max than by 4 min running at 80% or 60% VO2max. Short duration with high intensity exercise, such as 4 min running at 100% VO2max or 8 min running at 80% or 60% VO2max, is effective to stimulate type IIX fibre and IIA/IIX fibres that have the fastest speed of contraction.  相似文献   
99.
谢佳利  龙丹  王慧超  戴玄  陈今朝 《安徽农业科学》2013,41(3):1160-1161,1183
[目的]筛选出适合三峡库区退耕林下栽培的食用菌菌种。[方法]以棉籽壳、木屑、麦麸、麦秸等为主要原料,分别在室内和室外退耕林下栽培9种食用菌,筛选适合退耕林下栽培的食用菌菌种。[结果]在室内和室外退耕林下2种不同栽培环境中,茶树菇的产量最大、生物学效率和经济效益最高;平菇、姬菇次之。[结论]综合食用菌的产量、经济效益及栽培管理难易度考虑,筛选出适合在林下栽培的食用菌为茶树菇、平菇和姬菇。  相似文献   
100.
Meningiomas are one of the most common nervous system tumors in dogs. They are mostly solitary, benign, intracranial tumors of the transitional type. Tentative diagnosis can usually be made on historical data, clinical and neurological signs, and radiographs, with an antemortem diagnosis confirmed by exploratory surgery and histologic evaluation of biopsy. The literature contains many reports of the gross, histological and ultrastructural morphology of canine meningiomas, but little on the cytologic features of these tumors. This report describes the cytologic appearance of an intracranial meningioma in a 9-year-old Miniature Schnauzer.  相似文献   
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