Fungicidal impact on production of Sea oats (Uniola paniculata L.) plants from seed.

Coastal land loss is a significant issue in the Gulf Coast region of the United States.  To build and stabilize sand dunes native plants, such as Sea oats (Uniola paniculata L.), are incorporated in beach restoration projects.  Unfortunately sea oats seed yield and germination are low.  Objectives of this study were to assess impact of commercial fungicide(s) on sea oats germination, seedling survival, and seedling quality.  On May 31 and June 14, 2013 1,560 sea oats seeds were planted in soilless media under greenhouse conditions in Baton Rouge, LA, US.  Four fungicide treatments at two rates were immediately applied to seeded trays. SubdueMaxx® (1x: 0.019mL/1L; 2x: 0.004mL/1L) and Cleary©3336F (1x: 0.926mL/ 1L; 2x: 1.852mL/1L) were applied as soil drenches.  Abound® (1x: 0.785L/ha; 2x: 1.570L/ha) and Rovral® (1x: 1.753L/ha; 2x: 3.504L/ha) were applied as surface sprays.  Two controls: one soaked in water for 15 minutes prior to seeding and one not soaked or dry seed had no fungicide application.  Every 7 days after planting, germination was measured and seed considered germinated if coleoptile or radicle was visible.  Beginning 14 days after seeding, seedling survival was measured every 7 days; live seedling had visible green color.  56 days after seeding, seedling shoot height, root length, and fresh weight were measured.  Preliminary analyses found germination highest for seed treated with Abound®1x rate, Cleary©2x, Rovral®1x, Subdue®1x, Cleary©1x and non-soaked control.  In contrast, seed treated with Subdue®2x had lowest germination.  Sea oats seedling survival varied significantly between weeks.  At week 8 Cleary©1x and 2x rates had highest survival while Rovral®1x had lowest survival.  Shoot height was greatest for treatments Cleary©1x, Cleary©2x, Abound®1x, Abound®2x and Rovral®2x. These preliminary findings suggest fungicide application at seeding can improve greenhouse production of Sea oats plants from seed.