Reassessment of effects on lignification and vascular development in the irx4 Arabidopsis mutant

Analysis of Arabidopsis wild-type and irx4 mutant lines at various stages during growth and development revealed levels of lignin reduction in the mutant result from arrested/delayed development, presumably affected by modulation of CoASH metabolism. No evidence of any type for so-called abnormal lignification was obtained; instead, the deposition of lignin at all stages was predictably ordered.