节点文献
辣椒炭疽病菌生防菌的筛选、鉴定及应用
Screening, Identification and Application of Antagonistic Microbes to Colletotrichum Capsici
【作者】 杨青；
【导师】 易图永；
【作者基本信息】 湖南农业大学 ， 植物病理学， 2012， 硕士
【摘要】 辣椒炭疽病(Pepper Anthracnose)是辣椒上的重要病害之一,可引起辣椒幼苗死亡叶、烂果,通常病果率为15%左右,严重时病果率达30%-40%,是影响我国辣椒生产的主要障碍之一。因此,筛选对辣椒炭疽病菌有强烈抑制作用的生防微生物,是防治辣椒炭疽病的主要研究内容。本研究从贵州省的黄果树国家重点风景名胜区、湖南省的新宁崀山风景名胜区和张家界国家森林公园等地区的筛选到1株对辣椒炭疽病菌有较强拮抗作用的18号菌株,其发酵滤液稀释10倍后对辣椒炭疽病菌菌丝生长有较明显的抑制。18号菌株发酵滤液在稀释倍数为5倍、10倍和20倍后,对辣椒炭疽病菌分生孢子萌发的抑制率分别是74.9%、60.4%和50.7%。表明即使稀释20倍,18号菌株的发酵滤液对辣椒炭疽病菌分生孢子的萌发也具有较好的抑制作用。发酵液对辣椒种子萌发无明显影响。经过形态观察、生理生化试验以及16SrDNA序列分析,将18号菌株A鉴定为华丽黄链霉菌(Streptomyces flaveus)。室内离体接种试验和田间小区试验表明,18号菌株的发酵液对辣椒炭疽病有一定的防治作用,其发酵液稀释50倍后,辣椒炭疽病的病果减少率为64.76%,防治效果为75.74%。研究表明,18号菌株是很有潜力的辣椒炭疽病的生防微生物。
【Abstract】 Pepper Anthracnose caused by Colletotrichum spp is an economically important diseases of pepper cultivars, which can occur on leaves, stems, and both pre-and post-harvest fruits and lead to pepper fruit disease rate from10%to50%. Anthracnose disease is also one of the major economic constraints to pepper production in china. Therefore, screening antagonistic microbes to Colletotrichum spp is the main study target for pepper anthracnose control.Antagonistic microbes were isolated from soil collected from Huangguoshu Waterfalls in Guizhou province, Lang Mountain and Zhangjiajie National Forest Park in Hunan province, and it was found that one strain named No.18could obviously inhibit growth of Colletotrichum capsici and its spores germination. After treatment with No.18strain fermentation filtrate diluted by5times,10times and20times, Colletotrichum capsici conidiospore germination inhibition rates were74.9%,60.4%and50.7%respectively. This study further showed that fermentation liquid had no significant effect on seed germination of pepper.Based on morphological characteristics, physiological and biochemical test and16S rDNA sequence analysis, No.18strain was identified to Streptomyces flaveus. In vitro inoculation test and field experiments showed that No.18strain had an significant control effect on pepper anthracnose. When we treated pepper fruit with No.18strain fermentation filtrate diluted by50times, there was decrease(64.76%) in disease rate of pepper fruit and the control effect was75.74%. The experiments showed that No.18strain is a potential antagonist to control pepper anthracnose and can be used as a biocontrol agent.