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PAMP-triggered immunity (PTI) is the first layer of plant defense response that occurs on the plant plasma membrane. Recently, the application of a rhizobacterium, <i>Bacillus amyloliquefaciens</i> strain PMB05, has been demonstrated to enhance flg22_Pst- or harpin-triggered PTI response such as callose deposition. This PTI intensification by PMB05 further contributes to plant disease resistance to different bacterial diseases. Under the demand for rapid and large-scale screening, it has become critical to establish a non-staining technology to identify microbial strains that can enhance PTI responses. Firstly, we confirmed that the expression of the <i>GSL5</i> gene, which is required for callose synthesis, can be enhanced by PMB05 during PTI activation triggered by flg22 or PopW (a harpin from <i>Ralstonia solanacearum</i>). The promoter region of the <i>GSL5</i> gene was further cloned and fused to the coding sequence of <i>gfp</i>. The constructed fragments were used to generate transgenic <i>Arabidopsis</i> plants through a plant transformation vector. The transgenic lines of At<i>GSL5</i>-GFP were obtained. The analysis was performed by infiltrating flg22_Pst or PopW in one homozygous line, and the results exhibited that the green fluorescent signals were observed until after 8 h. In addition, the PopW-induced fluorescent signal was significantly enhanced in the co-treatment with PMB05 at 4 h after inoculation. Furthermore, by using At<i>GSL5</i>-GFP to analyze 13 <i>Bacillus</i> spp. strains, the regulation of PopW-induced fluorescent signal was observed. And, the regulation of these fluorescent signals was similar to that performed by callose staining. More importantly, the <i>Bacillus</i> strains that enhance PopW-induced fluorescent signals would be more effective in reducing the occurrence of bacterial wilt. Taken together, the technique by using At<i>GSL5</i>-GFP would be a promising platform to screen plant immunity-intensifying microbes to control bacterial wilt.