青枯病拮抗菌株90B4－2－2在番茄根部的吸附渗入和转移

ADSORPTION PENETRATION AND MOVEMENT OF BACTERIAL WILT ANTAGONISTIC STRAIN 90B 4-2-2 IN ROOTS OF TOMATO PLANTS

采用对青枯病有良好防效的菌株９０Ｂ４－２－２菌液浸种、泼浇苗床以及使用扫描电镜进行根、茎的观察，发现该株细菌在番茄根际土壤中能够繁殖，并向根部聚集和渗透；进入根部的细菌可向上转移至茎部和叶片；能在植物体内继续繁殖；并表现出具有催芽和壮苗作用。扫描电镜观察到该菌定殖于根或茎韧皮部薄壁细胞内。

It was found that cells of strain 90B 4-2-2 could multiply, accumulate in rhiosphere soil around tomato plants, as well as penetrate into roots and move up towards stems and leaves, where cells continued to multiply; in addition, the suspension of strain 90B 4-2-2 could accelerate germination of tomato seeds and make seedlings vigorous in case of soaking seeds in the suspension containing 2×109 CFU/ml for 30 minutes and drenching seedling bed soil with 125ml suspension containing 5×1010 CFU/ml or 2. 5×1010CFU/ml/m2. Observing roots and stems of tomato seedlings under scanning electron microscope showed that cells of strain 90B 4-2-2 colonized in thin-walled cells of the phloem of stems or roots of tomato plants which were susceptible to Pseudomonas solanacearum.