<p>(a, b and c). Expression patterns of 71 MAPKKK genes in the three tissues. (a). ZIK family genes. (b). MEKK family genes. (c). Raf family genes. (d). Relative expression levels of the MAPKKK genes in various tissues based on qRT-PCR analysis. The expression in leaf is shown on the left. The expression in stem is shown on the right.</p