Journal of Plant Diseases and Protection, cilt.130, sa.3, ss.609-617, 2023 (SCI-Expanded)
Tomato bacterial canker and stem rot are two of the most devastating bacterial diseases of tomatoes worldwide. Tomato cultivars that are resistant to these diseases are not available; thus, alternative control strategies are needed. In this study, the foliar spray effect of five individual phosphites and a fungicide on tomato bacterial canker and stem rot disease development, chlorophyll concentration, dry weight and stem diameter was investigated under controlled greenhouse conditions in two pot experiments. Phosphites inhibited the growth of Clavibacter michiganensis subsp. michiganensis (Cmm) between 50 and 74%, and raised the chlorophyll concentration estimated by SPAD measurements of tomato leaves up to 30% in phosphite sprayed plants. Likewise, phosphites reduced Pectobacterium carotovorum subsp. carotovorum (Pcc) development among 31% and 82% and induced an relative increases in chlorophyll concentration compared to control. Since the increase in dry weight (up to 15%) and stem diameter (up to 3%) of tomato plants varied in the first experiment, no increase observed for the second experiment. Additionally, no statistically significant differences (P ≤ 0.05) were figured out in dry weight and stem diameter of tomato plants compared to positive controls in response to both diseases. These results indicated that phosphites could be included effectively in tomato bacterial canker and stem rot disease management.