SUSCEPTIBILITY OF VARIOUS CROP AND WEED SPECIES TO AAL-TOXIN, A NATURAL HERBICIDE

AAL-toxin, produced by Alternaria alternata, was investigated for its phytotoxic effects on 86 crop and weed species. On susceptible tomato leaf discs, AAL-toxin caused electrolyte leakage and chlorosis at 0.01 muM in 24 h. Plants tested exhibited a range of response. AAL-toxin d amaged sensitive plants at 5 muM while other plants showed minimal dam age at > 1000 muM. Cotton and the important weeds, Canada thistle, fie ld bindweed, and velvetleaf were largely unaffected. Monocots tested w ere largely immune.