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91.
黑斑病是大白菜重要病害之一,常对大白菜田间生产造成严重损失。为明确引起贵州省六盘水地区大白菜黑斑病的病原菌种类,采用稀释涂布法从六盘水地区4个种植点大白菜黑斑病病样上分离到4个菌株。基于形态学和ITS、Alt-a1、tef-1多基因序列分析,4个菌株的鉴定结果均为芸薹链格孢Alternaria brassicae。生物学特性研究表明,该病原菌最适培养基为PDA,最适氮源为酵母浸粉和蛋白胨,最适碳源为葡萄糖;菌丝生长及孢子萌发最适温度均为25 ℃,菌丝生长最佳pH值为7;分生孢子致死温度为55 ℃下处理10 min。 相似文献
92.
Summary Methods developed to identify genetically diverse varieties of beans (Phaseolus vulgaris L.) were applied to closely related lines that were difficult to distinguish on the basis of seed morphology. Seedling tissues and seeds of black beans, were examined electrophoretically for isoenzyme and cotyledon proteinn protein patterns. Seven enzymes, extracted from seeds or from seedling stem, root or leaf tissues, were compared for polymorphism. Peptidase, polyphenol oxidase, phosphoglucoisomerase and glutamate oxaloacetate transaminase patterns were the same for all lines. Some differences were observed for acid phosphatase, peroxidase and esterase patterns, but complete discrimination of the six selected lines was not possible on the basis of isoenzyme patterns alone. Using polyacrylamide gel electrophoresis (PAGE) of dissociated 0.1 M acetic acid soluble proteins at pH 3.1 (acid-PAGE), or sodium dodecyl sulphate PAGE (SDS-PAGE) of residual protein extracts, all but one pair of samples in each case could be distinguished from the other samples. Using both techniques all of the lines could be identified unequivocally. 相似文献
93.
Drought tolerance combined with resistance to black sigatoka (BS) disease are two desirable traits for plantains in some parts
of the tropics. Field evaluation of leaf stomatal conductance, single leaf transpiration rate, photochemical efficiency, and
role of stomata in BS resistance, was done for 18 genotypes of Musa spp., which included diploid and triploid banana and plantains
and tetraploid plantain hybrids, at a sub-humid and a humid site. Conductances were significantly (P ≤ 0.01) higher for leaf
abaxial than adaxial surfaces (S), while clonal (C) differences were significant (P ≤ 0.05). Interactions between sampling
period (T: morning vs afternoon) and location (L), and clone and location (C × L) were significant for both conductance and
transpiration; (C × T × L) interaction was significant for conductance. Significant interactions for (C × L) and (C × T) suggested
that conductance and transpiration of a specific clone need to be considered for a given environment. Total variation in conductance
was explained by the following variables: S, C, (C × L), (C × T), and (C × L × T). In general, ABB cooking banana had higher
conductances than other Musa taxonomic groups (AAB, AA, AAA, and AAAB). Evaluation of morphological and physiological traits
of leaf stomata indicated that the resistance to BS disease is due to non-stomatal mechanisms.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
94.
水稻黑条矮缩病毒的研究进展 总被引:1,自引:0,他引:1
水稻黑条矮缩病毒(Rice black streaked dwarf virus,RBSDV)属于呼肠孤病毒科斐济病毒属第二组成员,其引起的水稻黑条矮缩病在中国稻区造成巨大的经济损失。文章简述了水稻黑条矮缩病的危害情况及病毒特性、病毒各个编码蛋白的研究现状、应用基因工程控制病害等方面的研究进展,为今后对水稻黑条矮缩病的研究提供参考。 相似文献
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96.
为进一步研究烟草黑胫病对烟叶品质的影响,在相同的田间条件下,以烤烟‘红花大金元’(以下简称‘红大’)、‘K326’和‘云烟85’品种为材料,比较了不同烤烟品种的生理指标、黑胫病发病率和相关化学成分之间的关系。结果表明,‘红大’品种的黑胫病发病率、病情指数最高,‘K326’次之,‘云烟85’最低;‘云烟85’的POD、PPO、CAT抗性酶活性和总酚、类黄酮含量接种时最高,且增加量最大,‘K326’次之,‘红大’最小;PPO、CAT、POD活性和类黄酮、总酚含量呈负相关关系,与蛋白质、可溶性糖含量呈正相关关系。 相似文献
97.
为研究不同茶树品种对滇红碎茶品质的影响,以国家级茶树良种‘云抗10号’为对照,选取省级茶树新品种‘云茶红1号’、‘云茶红2号’和‘云抗12号’3个茶树新品种为试验对象,按照统一采摘标准及加工方法制成手工滇红碎茶,比较主要生化成分测定结果和感官审评结果。结果表明:3个茶树新品种茶样的内含物质丰富,生化成分比例协调;感观审评5项因子的评分结果有2个品种比对照高,得分从高到低依次为‘云抗12号’、‘云茶红2号’、‘云抗10号’、‘云茶红1号’,说明3个茶树新品种均可作为生产滇红碎茶的选用品种,尤其以‘云抗12号’、‘云茶红2号’为宜。 相似文献
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100.
The activation of black soil (analog the lignite) by electro-hydraulic impulse is proposed. The abundant insoluble nitrogen, phosphorus, potassium and other organic elements in black soil are activated as the green fertilizer by this way. The new method is provided for activating sludge produced by treating wastewater. For several kinds of black soil, the experiment result indicates that electro-hydraulic impulse increases the percentage of absorbable nitrogen by 1 to 4 times and the percentage of insoluble organic elements by 4 times, which is a valuable reference to sludge treatment. 相似文献