2.The Legume-Root Nodule Symbiosis 根瘤菌与豆科的共生 Legume plants Rhizobium Symbiotic nitrogen fixation 11 Microbiology,Shanghai Jiao Tong University11 Microbiology, Shanghai Jiao Tong University 2. The Legume–Root Nodule Symbiosis 根瘤菌与豆科的共生 Legume plants Rhizobium Symbiotic nitrogen fixation