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 and seed 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.Abbreviations: PCA, principal component analysis.

Seed yield and quality of interspecific hybrids of Paspalum plicatulum × P. guenoarum at different harvest times

“…Sward age has a strong effect on Paspalum SY, and greater seed production has been observed in the first year of production. Previous research on P. plicatulum (Chadhokar & Humphreys, 1973) and P. notatum (Rios et al., 2020) showed most of the response variables, except seed weight, exhibited significantly better performance during the first year of production. Therefore, productive behavior over time requires more research.…”

Association between seed production traits in Urochloa spp.

“…Considering Urochloa , the mean number of filled seeds per individual (%) for eight different hybrids was 4.6% (Ragalzi et al., 2021). For bahiagrass ( Paspalum notatum Flüggé) genotypes, GP ranged from 5.1% to 39.3% (Rios et al., 2020). The percentage of filled grains is also one of the main factors that affect rice yield (Yoshida, 1981).…”

“…DTF was the only trait that decreased in Year 2 (Figure 3), which may be an indication that a greater number of days for flowering leads to a decrease in seed production. One of the factors that affect productivity and seed quality in Paspalum notatum is the prolonged flowering period (Rios et al., 2020). In forage grasses, the components of seed production are determined from vegetative development to the stages of reproductive development, highlighting the number of inflorescences and the number of flowers per inflorescence (Lopes & Franke, 2011).…”

Seed yield and quality of Paspalum notatum Flügge intraspecific hybrids

“…produced a higher seed set during the first year of seed production. Adjei, Mislevy, and Chason (1992) and Gates and Burton (1998) found a year effect and interaction with other factors on the seed yield of diploid bahiagrass, and Rios et al (2020) found that for bahiagrass, most of the response variables, except seed weight, exhibited significantly better performance during the first year of production. These contrasting results, observed by different authors and in this study, indicate that observed variations in seed yield in the first year of cultivation are more strongly influenced by climatic conditions than factors related to pasture age.…”