Changes in agronomic practices and incidence and severity of diseases in winter wheat in England and Wales between 1999 and 2019

Abstract

In continuation of the annual national surveys of winter wheat, which began in 1970, samples from between 250 and 350 randomly selected wheat crops in England and Wales between 1999 to 2019 were visually assessed for disease symptoms during the milky ripe development stages (GS 73–75). Septoria tritici blotch was the most prevalent and severe foliar disease each year, although annual levels fluctuated considerably and there was no overall significant change over the two decades. Incidence of brown rust, yellow rust, take‐all, and barley yellow dwarf virus also showed no significant overall change during the survey period, whereas glume blotch, powdery mildew, eyespot, and sharp eyespot all showed significant decline. Fusarium ear blight has significantly increased in both incidence and severity, causing a serious epidemic in 2012, when 96% of crops were affected. Tan spot has been the third most prevalent foliar disease since 2009 although severity is still very low. Regional disease levels were consistent over the two decades, providing reliable baselines to measure changes in seasonal disease severity. There were significant changes in agronomic practice with a rise to predominance of minimum tillage over the use of ploughing, decreases in overall disease susceptibility of cultivars grown, a major increase in the use of oilseed rape in the rotation and a long‐term trend towards earlier sowing. Fungicide use increased considerably, with over 98% crops sprayed and an average of 3.5 applications made per crop each year since 2014. Implications of changes over the last 21 years are discussed.

Pydiflumetofen Co-Formulated with Prothioconazole: A Novel Fungicide for Fusarium Head Blight and Deoxynivalenol Control

“…The lack of any additional control from AscraXpro compared to Proline agrees with previous studies showing low activity of SDHI in general against F. graminearum [20,27]. In the UK, the T2 timing (GS39) is a key timing for control of foliar pathogens of wheat and has the largest application area of SDHI fungicides for wheat [28]. Any benefit from a SDHI fungicide applied at T2 to reduce subsequent FHB infection at flowering and DON contamination in harvested wheat grain is therefore an additional reason for the selection of a particular product over another.…”

Azole Use in Agriculture, Horticulture, and Wood Preservation – Is It Indispensable?

“…Winter wheat crops mostly receive between one and four fungicide treatments per season, depending on the climate and regional differences (Jørgensen et al, 2014;Turner et al, 2021). Fungicide use in other cereals, such as barley, rye, and oat crops, is less frequent; up to twice per season (Jalli et al, 2020).…”

“…In areas with fewer humidity events and fewer treatments required, yield responses from fungicide treatments are commonly lower; in the range of 0.5 to 1.0 t/ha (Jørgensen et al, 2014). Data from the England and Wales show that the number of fungicide treatments per season since 2014 has exceeded 3.5 times on average, and azoles are used on all farms and are included in more than 80 % of the treatments carried out as T1 (growth stage (GS) 32-33 BBCH), T2 (GS 39) and T3 (GS 59-65) (Turner et al, 2021). Data from Germany and Denmark have also shown a widespread use of azoles in winter wheat (Lamichhane et al, 2016;Heick et al, 2020a).…”

Response of Indian Dwarf Wheat and Persian Wheat to Sowing Density and Hydrothermal Conditions of the Growing Seasons

“…The incidence of fungal diseases is also a known factor significantly affecting the size of wheat crops [26][27][28]. Among them, the ones most often observed on the leaves of wheat plants are powdery mildew (caused by Blumeria graminis), Septoria leaf spot (caused by Zymoseptoria tritici, synonym Septoria tritici) and wheat leaf rust (caused by Puccinia recondita).…”

“…For pathogens whose spores are easily spread by raindrops splashing from the lower infected parts of the plant to the upper leaves, the closer the leaves are to each other, the easier the spores are spread to the upper parts [33]. The incidence of disease symptoms in wheat crops also depends on various agrotechnical practices, including the date and density of sowing [28,34]. This effect may be direct, but often the sowing method indirectly influences the incidence of diseases on plants [35].…”