The accessions in the second group had shorter growth period and plant height, bigger seed size and determinategrowth habit etc. They were mainly from the northeastern and northern regions of China.
第二组群，生育期较短，植株较矮，子粒较大，有限生长，主要来源于东北及华北地区；
2
Using wind velocity profile law determinate the aerodynamic roughness length of wheats different growth periods: the average roughness of shooting period, is 6.