With summer temperatures climbing under sunny skies in August, many sand-based golf greens and sport pitches will quite literally burn up. Even those with automatic irrigation running overnight are seeing plants under intense stress by the end of each day.
Whilst supplementary hand watering can help alleviate the worst excesses, on seven of the hottest days across the south of England in July temperatures peaked above 26Â°C after 3.00pm in the afternoon – when most ground staff who started early in the morning had left for the day.
Water use efficiency is an increasingly important issue for all turf managers, both economically with the increased costs involved and environmentally to make use of available resources, according to Simon Barnaby of Syngenta. “It is also essential for plant health and turf quality,” he adds. “Turf that is repeatedly put under drought stress will be more susceptible to disease and other problems.
“Temperatures within the turf sward can frequently reach 10Â°C higher than the ambient air temperature, and since plant photosynthetic rates and chlorophyll production is inhibited above 24Â°C and roots affected when it reaches above 18Â°C, the current conditions are seriously challenging turf health.”
Research at Rutgers University in the US has shown that only 3% of water taken up by turf grass is used in photosynthesis, with over 90% transpired by the plant. Primo MAXX has been shown to improve the turf plant’s water efficiency by reducing respiration rates and stomatal evapo-transpiration.
In trials under drought conditions Primo MAXX enhanced the photochemical efficiency of turf by over 75%, compared to untreated turf. The relative water content of the grass leaves remained a healthy 20% higher than untreated 28 days after treatment. In the UK, turf mangers’ experience reports that a Primo MAXX programme can reduce irrigation requirements by 30%, whilst keeping turf greener and healthier for longer.
Furthermore, Mr Barnaby reports research that has shown that Primo MAXX applications increase the level of bioactive cytokinins within the plant. “Cytokinins have been shown to delay the degradation of chlorophyll caused by high temperatures and to alleviate leaf browning – improving tolerance to heat and drought induced stress, as well as improving turf quality. Under drought conditions, Primo MAXX has been shown to increase leaf chlorophyll content by up to 60%.”
Healthier plants, with deeper rooting encouraged by a Primo MAXX programme, are also better able to seek out available soil moisture and nutrients, and stay green and healthy for longer, as well as recovering faster from drought effects or traffic and wear stress from heavy play.
Syngenta turf management www.greencast.co.uk