Allelopathic effects of acetone extract from celery rotten roots and rhizosphere soil on cucumber pathogen Fusarium oxysporum f. sp. cucumerinum

Abstract

We studied the inhibitory effects of allelochemicals extracted from celery (Apium graveolens L.) rotten roots and rhizosphere soil on Fusarium oxysporum f. sp. cucumerinum (FOC). The allelochemicals were extracted and separated by column chromatography from the acetone extracts of celery rotten roots and rhizosphere soil. After extraction each fraction was mixed with potato dextrose agar (PDA) culture medium and then inoculated with FOC. The best fraction was screened by measuring the colony diameter and its effects on FOC was determined by evaluating the activities of antioxidant enzymes. The allelochemicals of best fractions were detected using GC-MS. The best fractions obtained after second run in column chromatography were labeled as RRA32, RRA38, RRA101, RRA102 and RRSA55, RRSA56, RRSA105, RRSA106 and they had allelopathic potential of 29.68 %, 31.97 %, 40.38 %, 41.55 % and 29.51 %, 29.47 %, 29.30 % and 32.85 % respectively. The antioxidants enzymes (peroxidase, catalase and superoxide dismutase) activities were significantly lower in treated FOC than control. Using the 8-best fractions, the GC-MS analysis yielded, total 47 compounds viz., 7 organic acids, 17 esters, 1 phenol, 1 alcohol, 1 aldehyde, 5 nitrogen-containing compounds and 2 carbides.