Effect of Cuttings with Different Lignin Contents on Cutting Rooting of Tetraploid Robinia pseudoacacia Identification of QTLs for Lignin Content of Seed Coat in Brassica napus L. in Different Environments Decomposition of Plant Residue as Influenced by its Lignin and N Itrogen Content variation of Lignin and peroxidase activities from Damaged Pinus massioniana Advance in Studies on Genetic Variation of Lignin Content in Tree Species