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31.
正马铃薯(Solanum tuberosum)为茄科茄属植物,是全世界广泛种植的重要粮食作物~([1])。马铃薯为人们提供了丰富的营养物质,如碳水化合物、多种微量营养素和有利于健康的膳食纤维~([2,3])。马铃薯根茎腐烂病由多种病原菌引起,是马铃薯采后的主要病害~([4])。甘薯长喙壳菌也引起多种植物果实腐烂,如巴西首次报道甘薯长喙壳菌侵染鸡蛋  相似文献   
32.
[目的]探索防治石榴枯萎病的植物源农药。[方法]以石榴枯萎病菌为供试菌种,采用生长速率法,测定洋葱、甘草、胡椒、番茄茎尖和厚朴叶的提取液对石榴枯萎病病菌的室内抑菌效果。[结果]5种植物提取液对石榴枯萎病病菌均有一定的抑制作用,以不经稀释的提取液效果较好,其中,洋葱、甘草、胡椒提取液对供试菌种的抑菌率较高,分别为66.50%、69.01%、72.40%,番茄茎尖和厚朴叶提取液的抑菌作用次之,抑菌率为64.49%和61.48%。[结论]植物源农药提取液的原液对石榴枯萎病病菌的抑制作用最强,随着稀释倍数的增加,抑菌效果逐渐减弱。  相似文献   
33.
通过对万佛山自然保护区的多次野外采集和调查,研究发现万佛山地区分布的虫草分属6个种,分别为丝虫草Ophiocordyceps filiformis、珊瑚虫草Cordyceps martialis、粉被虫草C.pruinosa、下垂虫草O.nutans、亚黄蜂虫草O.oxycephala和莲状虫草C.nelumboides。其中下垂虫草和丝虫草最多,分别占总数的28%和23%。虫草的寄主涉及到鳞翅目的幼虫和茧、蜂的成虫、蜘蛛和蝽象,而主要寄主为鳞翅目的幼虫,占总数的58%。莲状虫草为中国大陆新记录种,此前仅在日本和中国台湾省有过报道。  相似文献   
34.
Ceratocystis wilt of cacao (caused by Ceratocystis cacaofunesta) is a dangerous disease and results in the death of the plant. This fungus was recently identified in the major cacao-producing regions of Brazil, and was observed to be more aggressive than isolates from other geographical locations. The objective of this study was to develop and test a consistent method to assess cacao genotype response to C. cacaofunesta, based on young plants (seedlings or cuttings). The fungus was inoculated by the deposition of propagule suspensions on cut stems. The parameters to assess disease progress were (a) disease incidence, (b) differences in mortality between the most contrasting cacao genotypes for resistance and susceptibility, (c) disease index, (d) consistency of response over time and (e) relative lesion heights. When seedlings were used for the analyses, the ICS-1 and TSH-1188 genotypes proved to be useful as genetic standards for susceptibility and resistance to C. cacaofunesta, respectively. Inoculum concentrations between 104 and 105 propagules ml−1 and the moment at which the disease incidence stabilized provided appropriate conditions for genotypic comparison. When ten cacao genotypes propagated by cuttings (clones) were assessed, the results confirmed TSH-1188 as the reference genotype for resistance to C. cacaofunesta, while the remaining clones could be grouped as resistant (CEPEC-2008), moderately resistant (CEPEC-2002, CEPEC-2007) and susceptible (CEPEC-2009, CCN-10, CCN-51, HW-25, PH-16, SJ-02). The analytical concepts and results were discussed in terms of their application in breeding programmes aimed at developing genetic resistance to Ceratocystis wilt of cacao.  相似文献   
35.
锰锌?乙铝600倍液、800倍液、1000倍液、1200倍液、1400倍液均对甘薯黑斑病有一定的防效,其中以600倍液(833ppm)防效最佳,800倍液次之,1400倍液最差;浸渍锰锌?乙铝溶液10分钟后,用水冲洗对防病效果产生影响,使得防治效果降低;延长浸渍时间可以提高防效,而溶液温度对药效基本上不产生影响;用锰锌?乙铝浸苗防治效果很差,仅为19.8%,种薯浸蘸防病效果较好。  相似文献   
36.
从落叶松八齿小蠹各虫态体内外、坑道及木材蓝变部位获得3株与落叶松八齿小蠹伴生的真菌,该3株菌可导致木材变色,与蠢害的发生存在密切关系.通过菌体的培养特性和形态观察、放线菌酮耐性及rDNA ITS序列测定,将3菌株确认为Ceratocystis fujiensis,为国内新记录种.3个菌株生长的最佳环境条件:温度为25℃,光照为全黑暗条件,pH值为5.0;最佳营养条件:培养基为PDA+落叶松韧皮培养基,碳源为蔗糖,氮源为酵母粉.3个菌株均具有较强的高温和低温耐受性,能够适应北方较大的温差,树体内的黑暗和酸性条件也比较适合菌株的生长.3个菌株对寄主落叶松具有明显的营养选择性,可利用的碳源种类较多,有机氮源利于菌株生长.  相似文献   
37.
An intergeneric cross has been made between Dendranthema crassum (kitam.) kitam. (2n = 90; ♀) and Crossostephium chinense (L.) Makino (2n = 18; ♂). Most of the hybrid embryos aborted at an early developmental stage. Using ovule rescue, it was possible to establish a single intergeneric hybrid plant showing 2n = 54 chromosomes. The leaf length, leaf width and epidermal hair density of the hybrid were all intermediate between those of the parents. However the flower diameter, number of tubular florets, epidermal hair height and epidermal hair length exceeded those of both parents. A genomic in situ hybridization approach was able to distinguish between the parental genomes in the hybrid plant.  相似文献   
38.
研究了从橡胶和松树变色木上分离到的长喙壳属(Ceratocystis sensu lato)和其他木材变色菌。证明引起这两种木材变色的主要真菌是Ceratocystisspp.,Ophostomaspp.,Lasiodiplodia theobromae和Sphaeropsissp.。进而研讨了其中之长喙壳属真菌的分类学和形态学特征,传播媒介,寄主范围,以及温度对长喙壳菌引起的木材变色速度、菌落生长、子囊壳的形成和对子囊孢子成熟的影响。  相似文献   
39.
In Indonesia, Acacia mangium plantations exceed 1.6 Mha contributing approximately 3.5% of the country’s GDP. The viability of these plantations is increasingly threatened by fungal pathogens, insect pests, squirrels, monkeys, elephants and wind damage. Studies indicate that the problem is growing and in some areas, fungal pathogens such as Ganoderma and Ceratocystis species have contributed up to 50% tree mortality by the fourth rotation. Multiple statistical procedures were employed to examine the influence of soil and topographical properties on tree survival (trees ha?1), wood production (m3 ha?1), and mortality associated with Ganoderma root rot, Ceratocystis wilt and by wind. Soil family level was found to be a good indicator of tree mortality. Plots with fine-loamy Typic Kandiudult soils had the highest tree survival and mortality associated with species of Ganoderma and Ceratocystis, but had the lowest incidence of mortality by wind. The degree of association between soil and topographic variables with tree survival, wood production and the cause of mortality were poor and inconsistent. Tree survival was slightly higher on upslope areas away from valley bottoms, and drier mid-slopes, ridges and hilltops, and very low pH (<3.3) soils. Wood production was also slightly higher in drier, elevated locations, away from valley bottoms. Mortality by wind was slightly higher in moist, poorly drained, low-lying valley bottoms and topographically flat areas. Our ability to further pinpoint the influence of topography and soil attributes on wood production and cause of mortality was greatly compromised by the lack of site-specific soil data, and potential misclassification of the cause of mortality. This study could not reliably or consistently relate tree survival, wood production or the cause of mortality to any one, or combination of, soil and topographic variables.  相似文献   
40.
选择奥地利境内阿尔卑斯山健康欧洲云杉为对象,研究室内接种蓝变真菌(Ceratocystis polonica)引起的寄主树木韧皮部和木质部解剖学特征的变化,揭示蓝变真菌引起欧洲云杉枯萎的机制.结果表明:接种1周后的4株欧洲云杉的木质部组织内,蓝变区域显著增加,4~6周后蓝变区域不再增加;而在接种无菌琼脂的2株对照欧洲云杉的木质部组织内,没有检测到蓝变区域.采用生物化学分析和组织定位技术,确定接种真菌和无菌琼脂的欧洲云杉木质部区域纤维素酶的分布和活性变化.接种2周后剥皮取样检测,接种真菌的4株欧洲云杉的木质部组织内纤维素酶含量大幅度增加,其等电聚焦电泳显示明显的纤维素酶酶带;而在接种无菌琼脂的欧洲云杉木质部区域,纤维素酶含量分布较少,其等电聚焦电泳显示微弱的纤维素酶酶带.进一步证明蓝变真菌分泌的纤维素酶能利用寄主欧洲云杉木质部的纤维素,蓝变真菌是致死阿尔卑斯山境内欧洲云杉的重要病原菌.  相似文献   
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