Abstract
PREMISE: Salt marshes in the North Atlantic United States are dominated by grasses from the genus Sporobolus, which are perennial C(4) plants known for tolerating saline, anoxic, and flooded coastal sediments. Establishing in vitro cultures of Sporobolus species remains a major challenge due to frequent seed contamination from ergot and endophytic bacteria in vegetative tissues. METHODS AND RESULTS: Here, we demonstrate that in vitro axenic cultures of Sporobolus alterniflorus can be established in four weeks and micropropagation chains in three months with a 75% success rate. Additionally, this method is easily transferable to other salt marsh grasses, such as S. cynosuroides. CONCLUSIONS: The strength of our method lies in bypassing adventitious regeneration or somatic embryogenesis. Instead, we remove the hypocotyls and endosperm, primary sources of fungal contamination, and induce adventitious roots in the epicotyl. We also detail culture- and PCR-based methods to screen for contamination in vitroplants of S. alterniflorus.