Plant Reproduction, Development and Biodiversity Our research focuses on the molecular basis of plant reproductive development and shoot apical meristem development. My laboratory has focused on three major areas: (1) analysis of the role of key homeobox genes, such as ATML1 and WUSHEL, and hormones (auxin) during post-zygotic plant growth and development using the model genetic system Arabidopsis, (2) pollination of flowers and postpollination ovary and fruit development using Phalaenopsis and Vanilla orchids (Orchidaceae), and (3) the photoperiodic control of flowering in the photoperiodic short-day plant, Pharbitis nil, the Japanese morning glory. Currently, we are engaged in multidisciplinary collaborative research on Vanilla planifolia and its Mesoamerican wild crop relatives (Vanilloideae, Orchidaceae) to study flower and fruit development, disease resistance (Fusarium), and critical issues facing small-holder farmers in food insecure and impoverished developing nations. We also maintain a collection of rare and endangered Vanilla species, including Vanilla planifolia wild-crop germplasm collected from the region of its evolutionary origin and related Vanilla species of Mesoamerican and South American origin.

Su, HS, Zhao, XY, Liu, YB, Zhang, CL, O’Neill, SD, and Zhang, XS (2009) Auxin-induced WUS expression is essential for somatic embryogenesis in Arabidopsis. The Plant Journal doi: 10.1111/j.1365-313X.2009.03880.x.. Zheng, CC, Potter, D., and O’Neill, S.D. (2009) Phytochrome gene expression and phylogenetic analysis in the short-day plant Pharbitis nil Choisy (Convolvulaceae): differential regulation by light and an endogenous clock. American Journal of Botany 96:1319-1336. Lu, P., Porat, R., Nadeau, J. A. and O’Neill, S. D. 1996. Identification of a meristem L1 layer-specific gene in Arabidopsis that is expressed during embryonic pattern formation and defines a new class of homeobox genes. The Plant Cell 8: 2155-2168. Porat, R., Lu, P., and O’Neill, S. D. 1998. Arabidopsis SKP1, a homologue of a cell cycle regulator gene, is predominantly expressed in meristematic cells. Planta 204: 345-351. Nadeau, JA, Zhang, XS, Li, J, and O'Neill, SD. 1996. Ovule development: identification of stage-specific and tissue-specific cDNAs. The Plant Cell 8:213-239. Zhang, XS, and O'Neill, SD. 1993. Ovary and gametophyte development are coordinately regulated by auxin and ethylene following pollination. The Plant Cell 5:403-418 Porat, R, Nadeau, JA, Kirby, J, Sutter, E, and O’Neill, SD. 1998. Characterization of the primary pollination signal in the postpollination syndrome of Phalaenopsis flowers. Plant Growth Regul. 24:109-117