Comparative Survey of Lignification in Aerial Organs during Development of Sugarcane (Saccharum officinarum L.)

Cell-wall lignification is among the new features that appeared as early plants began to adapt to land, possibly aiding in the development of more complex bodies. Saccharum officinarum L., a typical C4 plant with unique structure and anatomy, is one of the most important energy crops in the world with a very high yield of biomass. We analyzed lignification in the anatomy of leaf, sheath and stem, in sugarcane seedlings at four distinct stages of growth: germination stage, tillering stage, ground growth stage and maturation stage. Kranz anatomy with well-developed bundle sheath associated with Kranz mesophyll was observed but Kranz system was absent in large vascular bundles. Lignification of tissues and cells in sheath during early developmental stages is expected confirmed because during this stage, when stem tissue is absent in sugarcane, may be critical for the expansion of lignification and development of the stem and increasing the mechanical rigidity of the young plant. The lignified tissues and the intensity of lignification increased during later stages of development, especially in the stem. The most lignified tissues of the stem can be observed during the maturation stage and a little before it, which provides the stem with mechanical strength. These differentiation features may be linked to stem development, while the relevant changes in metabolites may be related to sucrose accumulation.