Five Nodulation Mutants of White Sweetclover (Melilotus alba Desr.) Exhibit Distinct Phenotypes Blocked at Root Hair Curling, Infection Thread Development, and Nodule Organogenesis

白花苜蓿（Melilotus alba Desr.）的五个结瘤突变体表现出不同的表型，这些表型在根毛卷曲、侵染丝发育和根瘤器官发生阶段均受到阻滞。