1. And about a half month phellogen will begin to appear in the callus near the surface.
大约半个月后,在靠近表面的愈伤组织中出现木栓形成层。

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2. And about a half month phellogen will begin to appear in the callus near the surface.
大约半个月后,在靠近表面的愈伤组织中出现木栓形成层。

来自互联网