Abstract：The fiber content of vegetable bean pod wall directly affects the taste quality and is an important
indicator for variety selection．In order to study the content and composition of bean pod wall fiber in different
germplasm resources，this experiment measured and analyzed the contents of crude cellulose，cellulose，
hemicellulose and lignin in pod wall of 158 accessions bean commercial germplasm resources；and then tested
the pod wall fiber content，lignin synthesis related enzyme activity and MDA content in 2 germplasm resources
with high and low crude cellulose content at different development stages，respectively．The results showed
that 158 accessions of bean germplasm resources could be divided into 3 categories according to their crude fiber content：the first category with high fiber content，the second one with medium fiber content and the third one with low fiber content．Lignin is the main factor causing bean pod wall fiber content increase．The higher the activity of superoxide dismutase（SOD），the more unfavorable to the accumulation of lignocellulose．The rising of malondialdehyde（MDA）and peroxidase（POD）enzyme activities can accelerate its lignification process．
