Absence of long chain aldehydes in the wax of the Glossy II mutant of maize

Wax from the glll mutant of maize lacks aldehydes, which constitute 20 % in the normal genotype. The absence of aldehydes is not associated with a block in the synthesis of alcohols. Moreover in contrast to the wild type, glll wax is characterized by a higher content of C₁₆ and C₁₈ free acids, with a clear defect in the synthesis of C₂₄, C₂₆ and C₂₈ homologues. The results from this study are taken as evidence that the wild type elongation-decarboxylation I (EDI) pathway, leading to the synthesis of all the wax classes of compounds except esters, may be split into an early (EDIa) and a late (EDIb) group of reactions. Mutant glll is apparently defective at the EDIa, governing the synthesis of C₂₄–C₂₈ fatty acyl chains.