Sea oats is a perennial grass native to the Gulf of Mexico and Atlantic coastal regions of the United States. It is adapted to withstand high wind velocities, sand movement, limited water or xeric situations, high evaporation rates, and extreme temperatures (Dahl and Woodard, 1977; Wagner, 1964; Woodhouse et al., 1968; Woodhouse and Hanes, 1967). Because of these characteristics and its ability to build and stabilize sand dunes, it is commonly used in beach restoration projects.
In Louisiana, most sea oats plants used in beach restoration projects are genetically identical. They are produced by vegetatively dividing and propagating clonal material in greenhouses and nurseries. Planting the same clone on a large scale reduces genetic diversity and threatens the success of the project (Kutner and Morse, 1996). A more desirable system would be to produce sea oats from seed (Knott et al., 2012). Production of sea oats plants from seed would not only increase genetic diversity of sea oats plants but would also reduce production costs (Nabukalu and Knott, 2013a).
Large-scale production of sea oats from seed has been limited in Louisiana for several reasons. First, limited seed production, possibly resulting from the majority of florets in a spikelet being sterile or incompletely developed or from aborted ovules, makes it difficult to acquire seed from natural ecosystems (Gould and Shaw, 1983; Wagner, 1964; Williams, 2007). Second, there is limited knowledge of seed storage conditions to prolong seed viability, which could compromise the integrity of the seed. Typically most seed are stored at 4 °C; however, recent research indicates sea oats seed storage should be at room temperature in sealed jars to maximize seed longevity (Nabukalu and Knott, 2013b). Finally, sea oats have extremely poor germination rates, typically around 30% to 40%. These limited germination rates have been attributed to seed dormancy and/or to pathogens, fungal or bacterial, that potentially reside internally, on the seed surface or in the immediate soil zone, which can reduce germination (Burgess et al., 2002; Hester and Mendelssohn, 1987; Nabukalu, 2013; Sharvelle, 1961). Additionally, these pathogens could parasitize the seed before or during germination, or revive later and attack the seedling as a latent infection (Arya and Perelló, 2010; Sharvelle, 1961). Fortunately, fungicide applications at seeding are a traditional and effective method of protecting seed from fungal pathogens, thereby aiding germination and improving seedling survival in field, nursery, and greenhouse conditions (Arya and Perelló, 2010). The objectives of this study were to assess the impact of commercial fungicides on sea oats germination, seedling survival, and seedling quality, such as shoot height and fresh weight.
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