Submitted to: Proceedings Sunflower Research Workshop
Publication Type: Proceedings
Publication Acceptance Date: 1/30/1998
Publication Date: N/A
Citation: N/A Interpretive Summary: All sunflower hybrids currently produced have the same cytoplasmic male sterility (cms) source derived from wild species H. petiolaris, a very alarming situation regarding the crop's genetic vulnerability. Research conducted over the past 25 years has been focused on the search of new cms sources and their fertility restoration genes. This study reported the cytological characterization of three cms sources (PEF1, ANL1, and the classical PET1), and the identification of fertility restoration genes using a set of 45 inbred lines. The three cms sources were similar regarding their male gametes abortion patterns. The three cms sources had different reactions to the 45 lines indicating their genetic differences. Now sources of fertility restoration genes were identified among the 45 lines for all the three cms and will be utilized for hybrid combination development.
Technical Abstract: A microsporogenesis and pollen fertility restoration study was conducted with three cytoplasmic male-sterile sources: CMS PET1, CMS PEF1, and CMS ANL1. Forty-five of Advant's elite lines were tested with these three sources to determine maintainers and restorers for each cytoplasm. A great similarity between CMS PET1, CMS PEF1, and CMS ANL1 was observed, in terms of male gamete degeneration, at the beginning of microspore development following the tetrad stage. The tested B lines for CMS PET1 were also maintainers for CMS ANL1 and CMS PET1. This allows us to convert B lines into the two new male-sterile cytoplasms quickly. Only one PET1 R line did not restore CMS ANL1, indicating a difference between the two cytoplasms. The pollen fertility restoration genes for the CMS PEF1 are much less frequent in the cultivated sunflower genotypes, so the use of CMS ANL1 as an alternative to CMS PET1 is more advisable.