内生拮抗细菌在哈密瓜植株体内的传导定殖和促生作用研究

Colonization and Conduction Dynamics of Endophytic Antagonistic Bacteria in Hami Melon Plants and Their Effects on Plant Growth-promoting

采用抗生素标记的方法研究了内生拮抗细菌P38和B167菌株在哈密瓜植株体内的定殖动态和对植株生长的影响.结果表明,接种方法显著影响P38菌株在植株体内的定殖和传导,并以浸种处理最佳,蘸根和灌根处理次之,喷叶处理最差;浸种可使P38菌株在根、茎、叶中良好传导和稳定定殖,随着植株的生长,根内菌量呈下降趋势,而茎、叶内的含菌量先上升后下降;P38菌株还具有促进哈密瓜种子萌发和植株生长的作用.B167菌株只在根内定殖,在体内的扩展性较差,不能进入叶片;它对植株的生长表现出一定的抑制作用.

P38 and B167, endophytic bacteria strains which previously exhibited biocontrol ability, isolated from Hami melon plants. Colonizing dynamics of the strains in root,stem and leaf of Hami melon plant and their effects on the plants growth were investigated after inoculated the strains marked with antibiotic-resistance by four delivery methods, including soaking seeds, pruned-root dip, soil drench and foliar spray. The results indicated that each of the four methods could led to colonization of P38 strain in Hami melon tissues, but the effectiveness of the delivery methods were different significantly. The soaking seeds was the most efficient method to deliver P38 into the tissues. The colonizing density of P38 for soaking seeds treatment was much more than pruned-root dip, soil drench and foliar spray. After inoculated with soaking seeds, the target strain P38 could colonize internal root tissues, conduct to internal stem,leaf and root stably,and its density decreased in root gradually while increased in stem and foliage then decreased as the plant growing. P38 strain also expressed the ability to promote seed germination and plant growth. Another strain B167 could establish in roots only, and not transfer into other tissues. It showed inhibition for the plant growth.