Submitted to: Plant and Animal Genome VX Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 11/15/2002
Publication Date: 1/9/2003
Citation: Jessup, R.W., Burson, B.L., Yang, M., Renganayki, K., Paterson, A.H., Hussey, M.A. 2003. Analyses of apospory-linked markers in floral tissues of buffelgrass [abstract]. Plant and Animal Genome Abstracts. Paper No. W-132.
Technical Abstract: Buffelgrass (Pennisetum ciliare (L.) Link syn. Cenchrus ciliaris L.) is an apomictic, warm-season forage grass grown throughout the arid and semi-arid tropics. It is an aposporous apomict, in which most genotypes reproduce by either obligate apomixis or facultative (sexual and apomictic) apomixis. However, rare sexual genotypes exist. The long-term goal of this project is to elucidate the molecular basis of apospory and other economically important traits in perennial forage grasses. Earlier in situ hybridization studies yielded 12 virtual subtraction-derived cDNAs that were preferentially expressed in various tissues within buffelgrass florets, including the reproductive structures (pistil and stamen). However, these cDNAs did not map near the locus (PApo1) exerting major control over apospory in buffelgrass. In this study, both cDNA-derived RFLPs and BSA-derived AFLPs that mapped near PApo1 were utilized. In situ PCR of these molecular markers was used to estimate: 1) their sequence copy number within buffelgrass chromosomes, and 2) their expression patterns in floral (including gametophytic) tissues of obligate apomictic, facultative apomictic, and sexual genotypes. Results of sequence homology, public database searches, in situ expression patterns, and genetic mapping data will be discussed.