1Department of Horticulture, Zhejiang University, Huajiachi Campus, Kaixuan Road 268, Hangzhou 310029, China.
2Key Laboratory for Horticultural Plant Growth, Development and Biotechnology, Agricultural Ministry of China, Kaixuan Road 268, Hangzhou 310029, China.
*Correspondence author: E-mail: jqyu@zju.edu.cn
Watermelon seedlings were cultured in nutrient solutions with or without activated charcoal to study the autotoxic potential of root exudates. The addition of activated charcoal improved the plant growth together with a decrease in wilting and phenolic contents. The residual solution after one cropping was highly phytotoxic to the seedlings of successive crop, as indicated by reduced biomass accumulation and root TTC-reducing activity in the roots. Furthermore, roots cultured in the residual solution increased phenylalanine ammonia-lyase (PAL) activity and phenolics and MDA contents. The phytotoxicity was alleviated by the addition of activated charcoal.
Allelopathy, autotoxicity, monocropping, phenolics, phenylalanine ammonia-lyase, reactive oxygen species, soil sickness
