Polycross Seed of Genetically Diverse Smooth Cordgrass (Spartina alterniflora) for Erosion Control and Habitat Restoration

Abstract

Although seed-based planting is common in crop systems, it is relatively a new concept in coastal erosion control and habitat restoration. This paper discusses the potential use of seed-based revegetation to accommodate large-scale erosion control using a highly diverse population of smooth cordgrass (Spartina alterniflora) from controlled polycross to attain desirable genetic diversity suitable for habitat restoration. Seed-based restoration provides a more versatile alternative approach to the current clonal revegetation technique in many regions, including the Gulf Coast of the United States. The objectives of this study were to (1) describe seed production and cultural aspects of the polycross population and (2) discuss the potential use of polycross seeds for direct seeding applications and other innovative restoration approaches using seed-derived planting materials. The polycross population was produced using 15 genetically diverse and high-seed producing smooth cordgrass lines selected from native populations. The average seed set of the polycross population was 58.5 ± 6.3% with an average germination rate of 82.2 ± 9%. As comparison, Vermilion, the only available smooth cordgrass cultivar, has a seed set of 20.6 ± 5% and a germination rate of 35 ± 8%. The average yield of S. alterniflora seed from the polycross population was 277.5 kg/ha, which is equivalent to approximately 26 million viable seeds. Seed can be stored in 100% humidity at a temperature of 2 ± 1°C for 6-9 months.