Influence of Pseudomonas fluorescens x Azospirillum brasilense and Prohexadion-Ca on Poa annua L. growth and spreading in turfgrasses | Influência de Pseudomonas fluorescens x Azospirillum brasilense e Prohexadion-Ca em Poa annua L. crescimento e espalhamento em gramados

English. This study addresses the challenge of managing Poa annua (annual bluegrass), a problematic weed in turfgrass systems such as athletic fields, golf courses, and ornamental lawns. Traditional control methods provide only temporary relief, and chemical controls have led to herbicide-resistant biotypes and environmental concerns. The research explores alternative strategies using Prohexadion-Ca (Regalis®) and Pseudomonas fluorescens x Azospirillum brasilense (Rhizoflo Premium®). A field trial was conducted with different seed mixtures, Poa annua seeding rates, and treatment regimens to evaluate the combined efficacy of these substances. Data on Poa annua ratio and overall grass growth were recorded and analysed. Results indicated that Regalis® significantly reduced Poa annua and overall grass growth, while Rhizoflo Premium® promoted turfgrass growth without specifically targeting Poa annua. Both treatments were effective regardless of initial Poa annua seeding rates, and seasonal temperature stress also played a role in reducing Poa annua populations. The study underscores the importance of integrated turfgrass management practices that consider treatments, seed mixtures, and environmental conditions to optimise turf health and reduce reliance on traditional herbicides. These findings provide valuable insights for developing more sustainable and environmentally friendly turfgrass management practices.

Portuguese. This study addresses the challenge of managing Poa annua (annual bluegrass), a problematic weed in turfgrass systems such as athletic fields, golf courses, and ornamental lawns. Traditional control methods provide only temporary relief, and chemical controls have led to herbicide-resistant biotypes and environmental concerns. The research explores alternative strategies using Prohexadion-Ca (Regalis®) and Pseudomonas fluorescens x Azospirillum brasilense (Rhizoflo Premium®). A field trial was conducted with different seed mixtures, Poa annua seeding rates, and treatment regimens to evaluate the combined efficacy of these substances. Data on Poa annua ratio and overall grass growth were recorded and analysed. Results indicated that Regalis® significantly reduced Poa annua and overall grass growth, while Rhizoflo Premium® promoted turfgrass growth without specifically targeting Poa annua. Both treatments were effective regardless of initial Poa annua seeding rates, and seasonal temperature stress also played a role in reducing Poa annua populations. The study underscores the importance of integrated turfgrass management practices that consider treatments, seed mixtures, and environmental conditions to optimise turf health and reduce reliance on traditional herbicides. These findings provide valuable insights for developing more sustainable and environmentally friendly turfgrass management practices.