Lignin is a complex, aromatic polymer that limits plant cell wall degradation. Genetic Engineering using an antisense system offers the way to modulate enzymes in the lignin pathway and lead to reduce lignin. Caffeic acid 3-O-methyltransferase (COMT) catalyzes the multi-step methylation reactions of hydroxylated monomeric lignin precursors, and is believed to occupy a pivotal position in the lignin biosynthetic pathway. The plasmid pMAS-COMT 10.907bp has COMT antisense to down regulate O-methyltransferase and reduce lignin level in maize and bar gene as selectable marker that confers glufosinate herbicide resistance under 35s promoter. Out of fifty transgenic lines expressed bar gene and COMT-Antisense, only, three lines have significant differences from wild type. The results of this study pointed to possible use of genetic transformation approach to minimize lignin content and consequently enhancing bioethanol production from cellulosic material (stover).
Key words: Zea mays, COMT- antisense, gene bombardment, lignin content
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