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Submitted to: American Society of Agronomy Meetings
Publication Type: Abstract Only Publication Acceptance Date: 5/7/2004 Publication Date: 10/31/2004 Citation: Jensen, K.B. 2004. Cytology and fertility of advanced populations of elymus lanceolatus (scribn. & smith) gould x elymus caninus (l.) l. hybrids. American Society of Agronomy Meetings. Interpretive Summary: Technical Abstract: Amphiploids are frequently made as a mechanism to introgress desirable traits and restore fertility in hybrids between diverse species. This study reports the cytology, fertility, and morphological characteristics of Elymus lanceolatus (Scribn. & Smith) Gould, E. caninus (L.) L., their F1 hybrids, advanced generations F7 and F8, and three generations of advanced amphiploid progencies (C1, C2, and C3). Meiotic chromosome associations in both species are typical of allotetraploids. Bivalent associations most frequently observed in the F7 and F8 were 14 bivalents. After multiple generations of harvesting available seed each generation, an increase in meiotic regularity was observed in the advanced F-generations. Aneuploidy in the amphiploids (C-generation) was observed in the C2 and C3 generations with chromosome numbers ranging from 47 to 56. The C1 generation had significantly fewer univalents per cell than the C2 and C3 generations. Combined across chromosome numbers, there was a significant decrease in the number of bivalents from 22.48 to 21.36 to 20.27 in each succeeding C-generation, respectively. After seven generations of seed increase, pollen stainability increased from less than 1% in the F1 hybrid to 87 and 85% in the F7 and F8 generations, respectively. Chromosome doubling significantly reduced pollen stainability in the C1, C2, and C3 generations as comparred to the parents and advanced F-generations. |
