The stems of trees and many plants usually contain a large amount of lignin which is difficult to be decomposed, so the efficiency of using them to extract biofuels is greatly reduced. At present, people have discovered a bacteria called Rhodococcus, which has the ability to decompose lignin in wood and other plants. 
Rhodococcus is easy to cultivate. At present, the gene sequencing of Rhodococcus has been completed, so Rhodococcus can be used to produce enzymes that decompose lignin on a large scale.
 it is believed that Rhodococcus can be widely used in mostly discarded stalks, thereby greatly improving the utilization rate of biofuels.