Dissertations and Theses @ UNI
Availability
Open Access Thesis
Keywords
Plant hybridization;
Abstract
Putative hybrids between Lysimachia guadriflora and L. hybrida were discovered in a marsh in Dickinson County in northwest Iowa. No previous reports of interspecific hybridization between these species were found in the literature. Ecological barriers usually separate the parental species; however, at this population, disturbances by grazing animals and yearly fluctuations in the water level allow them to exist sympatrically. The parental species have concurrent flowering periods, similar floral morphology and pigmentation, and are pollinated by non-specific pollinators. The disturbances also provide a wide range of microhabitats intermediate to those of the parents. Thus, hybridization has resulted because of the absence of external isolating mechanisms. The hybrids are morphologically intermediate to either parent. Two-dimensional paper chromatography of leaf flavonoids of the parental species showed a great number of compounds common to both species and a small number of species-specific compounds. The putative hybrids exhibited chromatograms with some species-specific compounds from both parents present, but there was no total complementation. No synthetic F1 individuals were available for chromatographic analysis. Reciprocal artificial crosses between L. guadriflora and L. hybrida produced seeds, but germination attempts were not successful. The pollen mother cells of the hybrids have irregularities at meiosis and reduced fertility. These internal barriers limit the amount of hybridization and backcrossing, thus allowing the parental species to maintain their identity. There is evidence that L. hybrida has been slightly introgressed by L. quadriflora, but there is little indication of gene flow from L. hybrida to L. quadriflora. The great similarities of L. guadriflora and L. hybrida in morphological characteristics and in leaf and flower flavonoid complements suggest close phylogenetic linkage between the two.
Year of Submission
1972
Degree Name
Master of Arts
Department
Department of Biology
First Advisor
Lawrence Eilers
Second Advisor
Erwin Richter
Third Advisor
Daryl D. Smith
Date Original
1972
Object Description
1 PDF file (53 leaves)
Copyright
©1972 Michael Owen Dillon
Language
en
File Format
application/pdf
Recommended Citation
Dillon, Michael Owen, "Biosystematic Evidence for Hybridization Between Lysimachia quadriflora Sims and Lysimachia hybrida Michaux (Primulaceae)" (1972). Dissertations and Theses @ UNI. 2491.
https://scholarworks.uni.edu/etd/2491
Comments
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