Managing forage and turf‐type bahiagrass for seed production

Abstract

Bahiagrass (Paspalum notatum Flüggé) is the most extensively cultivated perennial warm-season grass in the southeastern United States for pasture, utility turf, cover cropping, and soil stabilization. The University of Florida Institute of Food and Agricultural Sciences bahiagrass breeding program has recently selected several improved forage- and dwarf-turf-type tetraploid breeding lines. However, seed production andseed quality quantification is needed before proposing any of these lines for cultivar release. The objectives of this study were (a) to evaluate seed production in seven tetraploid bahiagrass breeding lines (two forage-type apomictic hybrids, and five turftype facultative apomicts) and the cultivar ?Argentine?, and (b) to determine the optimum management practices (defoliation timing [May, June] and N rate [0, 60, and 120 kg N ha−1]) to increase seed yield and quality. Six seed traits were evaluated during 2 yr (first and second production year) under a randomized complete block design in a strip-split-plot arrangement with three replications. Eight genotypes (main plot), two defoliation timings (subplot), and three N fertilization rates (sub-subplot)were tested. All breeding lines produced viable seed comparable with Argentine,although some of them exhibited very low reproductive efficiency. Nitrogen fertilization improved seed yield by increasing inflorescence density but did not affect seed quality traits. Defoliation in May produced greater seed yield, whereas defoliation in June resulted in greater seed quality, especially for turf-type genotypes. The information generated in this study will guide cultivar release(s) and will be used to develop targeted recommendation practices for seed production in the species.