Construction of sense and antisense expression vectors of PpCCR gene in Pennisetum purpureum and transformation to tobacco plants

Pennisetum purpureum is a perennial resource plant and widely cultivated in tropical and sub-tropical regions. High lignin, however, to some extent, restricts the full use of it. In order to investigate the effect on the lignin synthesis by the cinnamoyl-CoA reductase (CCR) gene, P. purpureum cv. Huanan was selected to construct sense and antisense expression vector and transformed into tobacco by Agrobacterium infection method. The transgenic plants were histochemically stained by Wiesner and Maule reagents. Results showed that the composition of lignin did not change significantly, however, PpCCR overexpressing tobacco transgenic lines increased lignified cells while antisense expression lines with cells arranged loosely. Furthermore, the red-brown was found on the base of stem of the transgenic line with lignin content reduced sharply in tobaccos of the CCR antisense expression. The results emphasized the importance of CCR on the lignin synthesis and a foundation was laid for the genetic improvement of elephantgrass.