摘  要：本研究从多年种植辣椒的田间采集了长势优良的植株根系，表面消毒后从中分离到1株内生细菌PEB40。该菌株能在铬天青（CAS）平板上产生较大的噬铁圈，还具有较好的产吲哚-3-乙酸（IAA）和溶解有机磷的能力，显示了很好的植物促生长潜能。盆栽试验显示，PEB40菌株对辣椒具有显著的促生长效果，施用该菌剂后，辣椒的结果数、产量、株高、展幅与空白组相比均存在显著的优势（P＜0.05），其中株高增加了18.9%，展幅增加了20.7%，产量增加了35.3%，表明内生菌PEB40对辣椒具有明显的促生长效果。根据其16S rDNA序列、进化树及形态特征分析，该菌为假单胞菌属（Pseudomonas）新种的可能性大。本研究结果表明，CAS平板可用于高通量快速筛选促生菌，所得菌株PEB40亦为进一步开发新型微生物肥料奠定了基础。

Abstract: In this study, the roots of capscium with good growth were collected from the field where they have been planted for many years. After surface disinfection, an endophytic bacterium PEB40 was isolated from the roots. This strain can produce siderophore to form larger iron phagocytic circles on chrome azurol S (CAS) plates and also has the ability to produce indole-3-acetic acid (IAA) and dissolve organic phosphorus, showing good plant growth potential. The pot experiment showed that the PEB40 strain had significant growth-promoting effect on capscium, and the yield, plant height and spread of capscium after applying the endophytic bacterium PEB40, and it had significant advantages compared with the blank group (P<0.05). The height increased by 18.9%, the spread increased by 20.7%, and the yield increased by 35.3%, indicating that the endophyte PEB40 has a significant growth promoting effect on capscium. According to the 16S rDNA sequence, phylogenetic tree and morphological characteristics, the PEB40 has a high possibility of being a new species of genus Pseudomonas. This study demonstrated that the CAS plate could be used for high throughput screen of bacteria with plant growth promotion potential, and the PEB40 shows a great potential for developing to microbial fertilizer.