Detection and identification of mulberry bacterial wilt and its pathogen using Fourier transform infrared spectra

To rapidly identify a newly emerging mulberry wilt disease in Zhejiang Province, this study compared Fourier transform infrared （FTIR） spectra of Enterobacter mori and Ralstonia solanacearum, which cause similar disease symptoms on mulberry. First, FTIR spectra were taken on E. mori and R. solanacearum, and then a comparison of mulberry branches infected with and without E. mori was performed based on FTIR spectra. Results for E. mori and R. solanacearum in the 4 000.00 - 500.00 cm－1 region showed 5 similar peaks with 3 of the similar peaks differing in intensity. Peaks at 1 399.10 and 1 079.45 were specific to E. mori; whereas, peaks at 2 973.49, 1 724.42, 1 380.60, 1 278.67, 1 185.12, 1 132.03, 1 100.51, and 979.31 cm－1 were specific to R. solanacearum. The FTIR spectra for healthy and infected mulberry branches showed 5 similar peaks in the 4 000.00 - 500.00 cm－1 region with 4 of the similar peaks differing in intensity. Peaks at 1 643.92 and 1 407.31 cm－1 were specific to infected branches; whereas, peaks at 1 635.83, 1 506.36, 1 423.59, 1 374.97, 1 328.57, and 1 108.82 cm－1 were specific to healthy branches. This study indicated that Fourier transform infrared spectra could provide a simple, intuitive, and fast technology for rapid detection and identification of mulberry bacterial wilt. ［Ch, 2 fig. 3 tab. 19 ref.］