Dayton Oki
Project Description
"Characterization of the Progamic Phase in Ruppia maritima"
Ruppia maritima is an aquatic angiosperm that grows in brackish inland, estuarine, and coastal waters. R. maritima exhibits water pollination, in which pollen grains are transported across the water surface to receptive stigmas. The goal of this research was to characterize the progamic phase, the life history stage between pollsen germination and fertilization, in R. maritima. In order to determine the rate of pollen germination, immature flowers were collected in the field and kept in individual aquaria in a greenhouse until the stigmas became receptive. The flowers were then hand-pollinated and collected at intervals of 5-15 minutes after pollination. Pollen grains germinated within five minutes after pollination and fertilization was achieved within an hour after pollination. Carpels were stained and imaged using light microscopy. The results of the study showed that consistently low number of pollen grains were present on most of the stigmas and considerably less amount of pollen grain germinations occurred. This reflects the degree of the reproductive success amongst the tested R. maritima pollen grains, as fertilization was not seen in abundant numbers. This study not only yields data regarding the progamic phase in R. maritima, but also provides insight into reproductive traits associated with successful water-pollination.
Ruppia maritima is an aquatic angiosperm that grows in brackish inland, estuarine, and coastal waters. R. maritima exhibits water pollination, in which pollen grains are transported across the water surface to receptive stigmas. The goal of this research was to characterize the progamic phase, the life history stage between pollsen germination and fertilization, in R. maritima. In order to determine the rate of pollen germination, immature flowers were collected in the field and kept in individual aquaria in a greenhouse until the stigmas became receptive. The flowers were then hand-pollinated and collected at intervals of 5-15 minutes after pollination. Pollen grains germinated within five minutes after pollination and fertilization was achieved within an hour after pollination. Carpels were stained and imaged using light microscopy. The results of the study showed that consistently low number of pollen grains were present on most of the stigmas and considerably less amount of pollen grain germinations occurred. This reflects the degree of the reproductive success amongst the tested R. maritima pollen grains, as fertilization was not seen in abundant numbers. This study not only yields data regarding the progamic phase in R. maritima, but also provides insight into reproductive traits associated with successful water-pollination.
Presentations
2016
Creighton Biology Department Research Colloquium
2017
Creighton Biology Department Research Colloquium
2018
National Conference on Undergraduate Research
Nebraska Academy of Sciences
Creighton Biology Department Research Colloquium
Creighton Biology Department Research Colloquium
2017
Creighton Biology Department Research Colloquium
2018
National Conference on Undergraduate Research
Nebraska Academy of Sciences
Creighton Biology Department Research Colloquium
Publications
Taylor, M.L. *B.L. Giffei, *C.L. Dang, *A.E. Wilden, *K. M. Altrichter, *E.C. Baker, *R. Nguyen, and *D.S Oki. Reproductive ecology and postpollination development in the hydrophilous monocot Ruppia maritima. American Journal of Botany 107: 689–699