Potato Review

www.potatoreview.com POTATO REVIEW MAY/JUNE 2021 29 BIOSTIMULANTS A different role to play It differs from other biostimulants, typically with higher amino acid content, which plays an earlier role in plant development, because it provides stress prevention throughout the season, said Dave. The highest returns in tuber yields were generated from three applications of Quantis at 2.0 l/ha, applied from tuber initiation through the bulking phase. Application trials had shown it was fully compatible for tank mixing with all the blight fungicides tested. Reporting results of the extensive Quantis trials last season, Dave outlined that of the 32 sites experiencing conditions of greater than 25⁰C for more than four hours through the application window, yields were an average 2.2 t/ha greater. The 14 sites that experienced a heat event in excess of 30⁰C over that period recorded an average 1.9 t/ha yield increase. In previous years of Quantis trials, the greatest effects on yield and tuber size were recorded in 2018, which coincided with an extremely hot and stressful growing season, he said. “It was notable from in season assessments that effects were apparent in the second phase of tuber bulking, when the crop came under extreme stress.” Reviewing historic weather has shown the variability in heat events fromseason to season and location, but at some stagemost crops will be subject to some effects, he warned. Furthermore, as climatic conditions have changed over recent years, extreme and prolonged heat periods are becomingmore frequent. Continued Syngenta field research in 2021 will look at refining application timings, Dave said. More controlled trials will also seek to tease out differences between varieties and other variables, such as irrigation and crop duration. Syngenta’s New Farming Technologies team is developing predictive heat forecasting models, with the aim to identify potential for precision targeting of applications prior to stress periods in the potato growing season, along with some other crops. New research funded at Nottingham University will also lead an in-depth investigation into how Quantis is working to alleviate heat stress and drought effects within potato plants. “Effects were apparent in the second phase of tuber bulking, when the crop came under extreme stress.” Potatoes under summer heat stress Continued Syngenta field research in 2021 will look at refining application timings The highest returns in tuber yields were generated from three applications of Quantis at 2.0 l/ha, applied from tuber initiation through the bulking phase