Effects of phenol 2,4-bis(1,1-dimethylethyl) on seedling growth of eggplant and Verticillium dahliae

Based on earlier research, phenol 2,4-bis(1,1-dimethylethyl) provides the resistance against the verticillium wilt in eggplant cultivars. We studied the effects of phenol, 2,4-bis(1,1-dimethylethyl) on germination and growth of eggplant, mycelium growth of Verticillium dahliae and incidence of verticillium wilt in bioactivity tests and field experiments. The low concentrations (0.05 mmol·L⁻¹) significantly increased the germination rate, germination index, vigour index and radicle length of eggplant, but the high concentrations (0.10–1.00 mmol·L⁻¹) inhibited all the germination indexes. In field experiment, the low concentration (0.05 mmol·L⁻¹) slightly promoted the stem diameter and dry weight, improved the root activity and polyphenol oxidase (PPO) activity but decreased the content of malondialdehyde (MDA), chlorohpyll and activities of phenylalanine ammonia-lyase (PAL) and peroxidase (POD). The growth of eggplants was stunted at high concentrations (0.10–1.00 mmol·L⁻¹). The mycelium growth of Verticillium dahliae was drastically decreased with the increasing concentrations (0.50 to 2.00 mmol·L⁻¹). The 0.05 mmol·L⁻¹ concentration proved most suitable to enhance the resistance against verticillium wilt and its control in eggplant.