论文部分内容阅读
对安徽省淮北市番茄植株根、茎、叶中内生细菌及其数量进行了调查和筛选,并测定了其抑菌活性。结果表明,番茄根、茎和叶中的内生细菌的数量分别为5.69×105、5.16×105和2.83×105CFU.g-1鲜重。根据分离部位和表型特征,从健康番茄植株体内分离到267株内生细菌,通过对峙实验,筛选到11株对番茄灰霉病菌有拮抗作用的菌株,占所分离内生细菌总数的4.12%。来自茎组织中的菌株XF136的抑菌效果最佳,抑菌带宽度达32.2mm。根据形态特征、生理生化特性、(G+C)mol%和16SrDNA序列分析,将菌株XF136鉴定为解淀粉芽孢杆菌(Bacillus amyloliquefaciens)。室内测定菌株XF136发酵滤液对灰霉病菌菌丝生长及分生孢子萌发的抑制作用,结果表明,菌株XF136发酵滤液可以抑制灰霉病菌菌丝生长和分生孢子萌发,且浓度越高,抑制能力越强;当发酵滤液浓度为20%时则完全抑制灰霉病菌菌丝生长和分生孢子萌发。盆栽防效试验结果表明,10%菌株XF136发酵滤液对番茄灰霉病防治效果与50%多菌灵600倍液相当,20%发酵滤液对番茄灰霉病的防治效果高于50%多菌灵600倍液。本研究表明,菌株XF136是防治番茄灰霉病潜在的优良生防菌株,具有良好的开发应用价值。
Endophytic bacteria and their numbers in roots, stems and leaves of tomato plants in Huaibei City of Anhui Province were investigated and screened, and their antibacterial activities were determined. The results showed that the endophytic bacteria in roots, stems and leaves of tomato were 5.69 × 105, 5.16 × 105 and 2.83 × 105CFU.g-1 fresh weight, respectively. According to the separation site and phenotypic characteristics, 267 endophytic bacteria were isolated from healthy tomato plants. Through the confrontation experiments, 11 strains that antagonized Botrytis cinerea were screened, accounting for 4.12% of the total number of endophytic bacteria isolated, . The antibacterial effect of strain XF136 from stem tissue was the best, and the antibacterial band width was 32.2mm. The strain XF136 was identified as Bacillus amyloliquefaciens according to morphological, physiological and biochemical characteristics, (G + C) mol% and 16S rDNA sequence analysis. The results showed that the fermentation filtrate of strain XF136 could inhibit mycelial growth and conidiospore germination of Botrytis cinerea, and the higher the concentration was, the less the ability of inhibiting the growth of conidiospores was. The stronger the fermentation broth concentration was, the lower the mycelium growth and conidia germination were. The results of pot experiment showed that the control effect of 10% strain XF136 fermentation broth on tomato gray mold was as good as that of 50% carbendazim 600 times, and the control effect of 20% fermentation filtrate on tomato gray mold was more than 50% 600 times solution. This study shows that strain XF136 is a potential excellent biocontrol strain against Botrytis cinerea, which has good development and application value.