Initial results from the HGCA Recommended List winter barley trials show wide variation between crops sprayed with fungicides and those that didn’t receive any treatment at all.
Although yields from the first trials treated with fungicide are similar to the five year average, tonnages from untreated plots are lower than average this year as a consequence of higher disease pressures.
The two main disease problems were brown rust and rhynchosporium. Mildew levels were high in Saffron and Cassata, both which are rated 3 and 4 for mildew, so there were no surprises there. Net blotch levels were, however, low in the untreated trials.
The fungicide programme used in RL trials is robust in order to keep out all diseases in all situations. This year we used an early spring clean up fungicide followed by two applications based around SDHI and triazole actives Siltra Xpro (bixafen + prothioconazole) and Bravo (chlorothalonil). Although growers may have preferred to see higher than average yields from our robust treatments, disease pressure and weather were such this season that using a combination of a triazole with an SDHI only resulted in average tonnages.
Untreated Retriever and SY Venture were particularly affected by high levels of brown rust and rhynchosporium. The fungicide programme we use is designed to protect crops from early rhynchosporium which would have flared up in the wet spring and also control brown rust which was more likely to develop later in the season.
Untreated KWS Meridian achieved a relatively high yield. At this early stage we can’t attribute the difference solely to disease, but it does highlight the need to look at varieties which provide a good treated yield and quality for your market. It’s also important to look at the untreated yield and disease ratings, since this will give growers an indication of what may happen if next season turns out to be another challenging year for disease.
Simon Oxley is the HGCA’s Recommended List manager