成团泛菌YS19 symplasmata结构对菌体抵抗逆境的作用

成团泛菌（Pantoea agglomerans）YS19是从水稻“越富”品种中分离出的优势内生菌，其所形成的共质体（symplasmata）是一种与生物薄膜（biofilm）类似的多细胞聚集体结构，但细胞间联系比biofilm更加紧密。研究symplasmata结构对成团泛菌YS19抵抗逆境的贡献，有助于阐释内生菌与植物的相互作用的适应性。比较研究了symplasmata结构与散生菌体对于蔗糖渗透压冲击、重金属离子和干燥处理的抵抗能力差异，结果表明，与以散生状态存在的菌体相比，在面临逆境时形成symplasmata结构的菌体抗逆存活能力显著增强。

The Effects of Symplasmata Structure of Pantoea agglomerans YS19 on Thallus Resistance against Unfavorable Circumstances

Pantoea agglomerans strain YS19 was a dominant endophyte isolated from rice cv, Yuefu. Symplasmata it formed was a film-like multi-cell aggregate structure; however, its intercellular connection was much tighter than that in biofilms. Study on the contribution of symplasmata structure to P. agglomerans YS19 against unfavorable circum- stances is conducive to explain the adaptability of the interaction of endophytes and plants. Symplasmata structure was comparatively studied with separated bacteria on the differences of resistant ability in osmotic shock, heavy metal ions, and arid treatment. The results showed that while facing unfavorable circumstances, thallus that forms symplasmata structure its survival ability apparently strengthen much more than those of separated bacteria.