@article{pinkney iv_iannone iii_milla-lewis_laat_unruh_schiavon_dale_2024, title={Investigating multi-trophic effects of St. Augustinegrass cultivar blends in the Southeastern United States}, volume={11}, ISSN={["1435-0653"]}, DOI={10.1002/csc2.21399}, abstractNote={Abstract Warm‐season turfgrasses, including St. Augustinegrass [ Stenotaphrum secundatum (Walt.) Kuntze], are produced and installed as monocultures of single cultivars. Recent research indicates that blending St. Augustinegrass cultivars can increase turfgrass stand resilience to insect pests, establishment of undesired plant species, and abiotic stressors without reducing plant performance. However, effects on specific key turfgrass insect pests are less documented and the mechanisms driving changes in turfgrass stand resilience are unclear. Moreover, it remains unknown if the effects of cultivar blends on biotic resistance vary across St. Augustinegrass’ range. Here, we pair a regional common garden observational field study with a controlled greenhouse experiment to isolate the effects of cultivar blends on the recruitment of predatory arthropods (top‐down pest regulation) and on southern chinch bug [ Blissus insularis Barber] performance (bottom‐up pest regulation). We find that cultivar diversity has no effect on natural enemy recruitment but natural enemies do vary predictably with changes in geographic location. In contrast to our hypothesis, southern chinch bug reached higher densities in cultivar blends compared to cultivar monocultures, although this effect was driven by specific cultivar blends. Despite higher pest densities in turfgrass blends on average, blends of four St. Augustinegrass cultivars maintained a higher percent green cover than cultivar monocultures, suggesting that cultivar blends can persist longer under elevated pest densities compared to cultivar monocultures. Our findings can guide future research focused on blending warm‐season turfgrass cultivars as an integrated pest management strategy for more resilient and sustainable turfgrass lawns.}, journal={CROP SCIENCE}, author={Pinkney IV, James Louis and Iannone III, Basil V. and Milla-Lewis, Susana and Laat, R. and Unruh, J. Bryan and Schiavon, Marco and Dale, Adam G.}, year={2024}, month={Nov} }
 @article{laat_leon_dale_gouveia_carbajal_schiavon_unruh_iannone iii_milla-lewis_2024, title={Molecular analysis of St. Augustinegrass cultivar mixtures composition over time and latitude}, volume={9}, ISSN={["1435-0653"]}, url={https://doi.org/10.1002/csc2.21370}, DOI={10.1002/csc2.21370}, abstractNote={Abstract St. Augustinegrass [ Stenotaphrum secundatum (Walt.) Kuntze] is commonly planted in residential and commercial landscapes as a cultivar monoculture predisposing this lawn to pest invasion and high‐maintenance inputs. Researchers have suggested that increasing genetic diversity by growing cultivars in mixtures may increase turfgrass stress resilience. However, the stability and uniformity of those mixtures has not been studied. The present study was carried out to evaluate the stability of St. Augustinegrass cultivars mixtures over time and across three latitudes. The study was conducted in Citra and Fort Lauderdale, FL, and Jackson Springs, NC. Simple‐sequence repeats markers were used to genotype leaf samples of St. Augustinegrass cultivars planted in two‐ and four‐cultivar mixtures. Leaf samples were collected 1 and 3 years after establishment. In all locations, cultivar richness and evenness declined over time. Similarly, the relative abundance of the least persistent cultivars decreased approximately 50%–100% depending on cultivar and location. Differences in growth patterns among cultivars resulted in cultivar displacement and the predominance of a single cultivar. Cultivars that covered the ground faster or formed dense canopies early after establishment were dominant at the end of the study. Locally developed cultivars tended to be more dominant in their original latitude. The use of cultivar mixtures may help the identification of vigorous, competitive, and stress tolerant cultivars in turfgrass breeding programs. However, their commercial use remains challenging as if the patterns observed here for 3 years are representative of a continuous trend, and they do not persist over time.}, journal={CROP SCIENCE}, author={Laat, Rocio and Leon, Ramon G. and Dale, Adam G. and Gouveia, Beatriz and Carbajal, Esdras M. and Schiavon, Marco and Unruh, J. Bryan and Iannone III, Basil and Milla-Lewis, Susana R.}, year={2024}, month={Sep} }