Potential Health Benefits of Pigment-containing Products on Creeping Bentgrass and Hybrid Bermudagrass

The objective of this research was to analyze the use of pigmented products in the management of heat stress on creeping bentgrass [Agrostis stolonifera L. var palustris (Huds.)] and low temperature stress on bermudagrass [Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt-Davy]. Studies utilized: zinc oxide (ZnO), green pigment + titanium dioxide (TiO2) (Turf Screen); Cu-based pigment (PAR); fosetyl-Al (Fosetyl-Al); fosetyl-Al + Cu-based pigment (Signature); potassium phosphite (KH2PO4) (Title Phyte); Turf Screen + Title Phyte; and, PAR + Title Phyte. Products were applied bi-weekly for 12 wk. Bentgrass canopy temperatures increased ~0.5 to 3°C, photosynthesis reduced ~6 to 20 µmol CO2 cm-2 s-1, and relative chlorophyll content decreased ~8.5% by treatments, while bermudagrass was unaffected. Bermudagrass field studies indicated reduced photosynthesis (~8 to 21 µmol CO2 cm-2 s-1) for Title Phyte, stressed control, and Turf Screen. Root mass was unaffected by treatments. Turf Screen alone and + Title Phyte increased Zn plant (~820 mg kg-1) and soil (4.75 kg ha-1) levels. PAR alone and + Title Phyte; and Turf Screen + Title Phyte increased tissue Cu ~27 mg kg-1. Overall, pigmented products promoted bentgrass heat stress and heavy metal accumulation but had minimum effect on bermudagrass turf performance.