Research Article - Journal of Agricultural Science and Botany (2025) Volume 9, Issue 2

MANAGEMENT OF ALTERNARIA ALTERNATA (FR.) KEISSLER BY THE EXTRACTS OF CENCHRUS PENNISETIFORMIS HOCHST. & STEUD.

Present research work was designed to examine the antifungal potential of extract of plant Cenchrus pennisetiformis Hochst. and Steud. against leaf spot and blight of tomato causing fungus Alterneria alternata (Fr.) Keissler Penz. In order to achieve this goal, methanolic extracts of test plant species were prepared to evaluate their in vitro antifungal activity against the fungus A. alternata. The 0.5% concentration was found highly effective of C. pennisetiformis caused 75.4% reduction against the A. alternata. According to phytochemical analysis C. pennisetiformis plant contain saponins, tannins, phlobatannins, alkaloids, flavonoids and glycosides. C. pennisetiformis with highest antifungal potential was further processed to partition with four organic solvents and among them the chloroform fraction was found as more effective fraction against the test fungus. Chloroform fraction 0.1% and 0.2% reduced fungal biomass up to 33.3% and 33.3% respectively. n-Hexane fraction also showed effective results. Nine bioactive compounds were recognized by the GC-MS examination of chloroform fraction of plant C. pennisetiformis. Major constituents were cyclopentasiloxane, decamethyl (9.02%), cyclohexasiloxane, dodecamethyl (4.37%), 3-Isopropoxy-1, 1, 1, 7, 7, 7-hexamet (1.84%), 2, 4-Di-tert-butylphenol (2.24%), 2-pentadecanone, 6, 10, 14-dimethyl (1.46%), pentadecanoic acid, 14-methyl-methyl ester (17.38%), 9, 12-octadecadienoic acid, methyl ester (3.08%), 6-octadecanoic acid, methyl ester (39.73%) and methyl stearate (4.03%). Six compounds were isolated from Preparative Thin Layer Chromatography (PTLC) by using chloroform fraction of C. pennisetiformis. Six compounds A, B, C, D, E and F were used for Minimum Inhibitory Concentration (MIC) assay effectiveness order for isolated compound was: compound D>compound E>compound F>compound A>compound B> compound C. Remarkable results were noticed when compared with control of water and DMSO treatment.

Author(s):

Fiza Iqbal*, Khajista Jabeen, Gulshan Riaz

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