Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 12/27/2011
Publication Date: 3/2/2012
Citation: Grusak, M.A. 2012. Germination ecology of the native legumes, Sesbania drummondii and Glottidium vesicarium [abstract]. Texas Academy of Sciences 115th Annual Meeting. p.54.
Technical Abstract: Sesbania drummondii and Glottidium vesicarium are native legumes that are active during the warmer months of the year; their seeds mature in the middle to late fall. Both species favor wet soils, including marshy areas, and the two legumes often coexist in the same habitat sites. Sesbania drummondii is a perennial and Glottidium vesicarium is an annual species. In order to assess the potential consequences of future climate change effects (including drought and increasing temperatures) on the continued presence of these legumes in the Texas environment, we characterized various germination phenomena in both species. Studies were conducted to measure physical and physiological dormancy, temperature and water potential optima for germination, and genotypic diversity for these traits. Seeds of both species demonstrated highly water impermeable seed coats, which conferred a state of physical dormancy. No physiological dormancy was apparent, as both species germinated soon after maturation if seeds were scarified to allow imbibition. Temperature optima for both species showed maxima in the 20 – 35 C range; germination was not noted below 10 C. Diversity of responses, based on studies with seeds collected from different locations and times of the year, will be presented. Results will be discussed in the context of the near-term and long-term prospects for these species persistence in the Texas landscape.