Relationship Between Free Proline Content and Male Sterility of Tobacco

The proline contents in flower buds and leaves of tobacco of cytoplasmic male sterile(CMS) lines and their maintainer lines were anazyled.The results showed that the proline content in CMS buds was close to that in maintainer line buds at small bud stage,however,it increased rapidly in maintainer line buds beginning from mid-size bud stage,while that in CMS buds was almost unchanged.Therefore,the proline content in CMS buds was obviously lower than that in maintainer line buds at big bud stage.There was no significant difference between free proline contents in leaves of CMS tobacco and maintainer lines,relatively obvious differences were observable at later breeding stage only,though the differences changed irregularly.It was indicated that there was a close relationship between free proline content in flower buds and male sterility of tobacco and there was no direct relationship between free proline content in leaves and male sterility of tobacco.The lower proline content in CMS buds was caused by male sterility of tobacco.