Abstract

                                he present study focused on divulging the effect of 15 and 30 days oldculture filtrates of Chaetomium globosum on the mycelial growth and toxinproduction of Fusarium oxysporum f. sp. lycopersici. The cell-free culture (CFC)filtrate of C. globosum was inoculated in the liquid medium of F. oxysporum f.sp. lycopersici. The results revealed that mycelial growth was reduced in theCFC filtrate of C. globosum inoculated medium compared to control (pathogenalone). The mycelial dry weight of the F. oxysporum f. sp. lycopersici was0.864g in fifteen days old CFC filtrate followed by 30 days old CFC filtrate of C.globosum (1.374g) amended medium. Metabolites from the CFC filtrate andcontrol were extracted separately using chloroform followed by ethyl acetateand the extract was subjected to GC-MS analysis. GC-MS analyses showedthat methyl ester group was present in 15 days old culture filtrate condensatecompared to 30 days old CFC. The compounds are methyl tetradecanoate,octadecanoic acid, methyl ester, and DL-Proline, 5-oxo-, methyl ester.Thirty days old culture filtrate condensate of C. globosum contained morephenol groups like phenol 2,4-bis (1,1-dimethylethyl) at 17.62 RT followedby diisooctyl phthalate, 17-pentatriacontene, cholestan-3-ol, 2-methylene-,(3a,5a) and bicycle [4.1.0]heptanes,-3-cyclopropyl,-7-hydroxymethyl,trans.Metabolites of F. o. f. sp. lycopersici were also characterized by GC-MS,which showed very few volatile compounds like methyl tetradecanone , oleicacid, eicosyl ester, methyl stearate, and bis(2-ethylhexyl)phthalate. Thesecompounds were not detected in co-inoculation of 15 and 30 days old CFCfiltrate of C. globosum and F. o. f. sp. lycopersici. The difference in thevolatile profile may be due to the effect of the metabolites of C. globosumon F. o. f.sp. lycopersici.

Key words : Culture filtrate condensate; Chaetomium globosum; Fusarium oxysporum f. sp. lycopersici