Investigating tradeoffs in perennial ryegrass turfgrass performance and seed yield capacity in the US Midwest

Understanding the trade-offs between improving turfgrass performance and seed production capacity would improve acceptance and accelerate the release of new perennial ryegrass (Lolium perenne L.) cultivars. An experiment was designed to measure the turfgrass quality, seed yield, and component traits among 20 perennial ryegrass entries grown in turfgrass and seed production swards at two locations in Minnesota, a seed production region of the United States. Turfgrass quality scores, when averaged across collection dates, were not strongly correlated with seed yield at either location. However, data from several individual turfgrass quality rating dates were moderately correlated with seed yield at both locations (p < 0.100). Within the dates that correlated with seed yield, turfgrass component traits were regressed against quality scores. Crown rust severity, color, and density were important in the first year, and winter injury and texture were important in the second year. Plots with more fertile tillers were associated with higher seed yield and lower turfgrass quality (p < 0.050), but there was no relationship between entries in the two growing environments for fertile tiller production (p > 0.250). Entries that exhibited a faster vertical growth rate in turfgrass swards tended to mature earlier in seed plots, a trait that was correlated with higher seed yield (p < 0.001). However, the vertical turfgrass growth rate was not directly correlated with seed yield (p > 0.800). Few tradeoffs between the growing environments were found under the growing conditions and germplasm employed.