An alteration in the cytoplasm reaction was provoked during the transfer of sunflower line M-C-5 into the cytoplasmic male sterility ARG-3. The new source of CMS was different from CMS ARG-3. The differences were proved by investigating the fertility restoration in hybrid plants produced with the participation of line M-C-5A in CMS ARG-3 as well as the restorer lines for CMS PET-1 and CMS ARG-3 - lines 147R, 7015R, 7042R and 7045R. Combinations M-C-5A in CMS ARG-3 and lines 7015R and 7045R gave 100% sterile hybrid plants, while combinations M-C-5A in CMS ARG-3 and lines147R and 7042R gave 60.3% and 23.8% sterile plants, respectively. As a result of the combinations between other nine lines in CMS ARG-3 and these four R lines, only fertile hybrid plants were produced. The hybrid plants obtained from combinations between line M-C-5A in CMS DEB-1 and CMS ANN-16 with line 7015R were also fertile. These facts led us to conclude that the mutation has been provoked in the process of transfer of line M-C-5A into CMS ARG-3. Thus a new different CMS source has arisen out of an existing CMS source and it was named CMS ARG-3-M-1. The newly obtained CMS source seems to be a separate type. The way of origination of CMS ARG-3-M-1 was entirely different from the already existing methods for obtaining CMS in sunflower.