Evaluation of Fungicide Efficacy on Sunflower Rust (Puccinia helianthi) on Oilseed and Confection Sunflower

Abstract

Sunflower rust, caused by Puccinia helianthi, is an economically and globally important disease of sunflower. Two types of sunflowers are produced in the US Northern Great Plains; the oilseed type and the confection type. Although approximately 80% of the acreage in this region is planted as the oilseed type sunflower, fungicide efficacy and timing studies have been conducted primarily on the more rust-susceptible confection type. A total of ten sunflower rust efficacy field experiments were conducted on oilseed type and confectionary type hybrid trials from 2016-2018. Eleven fungicides from three FRAC groups were evaluated for efficacy and protection of yield. Severity differences among fungicide treatments were identified in both confection and oilseed type sunflower trials. A combined analysis of all confection field trials (five) indicated that rust severity was lower in all fungicide treatments as compared to the non-treated control. Despite rust severity levels below the fungicide action threshold for confection sunflower, seven of the eleven fungicide treatments had yield higher than the non-treated control. In oilseed trials, rust severity was lower in all fungicide treatments as compared to the non-treated control, similar to the findings of the confection type. Rust severity was too low to detect yield differences in oilseed trials. Additional work is needed to elucidate yield-loss potential on oilseed type sunflower and refine the fungicide action threshold on confection type sunflower.

Status of Fungal Diseases on Sunflower Cultivars and Hybrids in Different Areas of Punjab Pakistan

“…These both diseases have also been reported during surveys in USA (Mathew et al, 2015;Harveson et al, 2018). We also reported the presence of charcoal rot, leaf rust, phoma black spot and powdery mildew diseases in different areas of Punjab, which is in line with the findigs of different researchers (Donald et al, 1987;Gulya et al, 2011;Harveson et al, 2018;Gilley, 2017;Berghuis et al, 2018). These researchers have confirmed their presence in different countries also.…”