Resilient Disease Control with Revystar® XE
4 Jun 2020
Fungicide application is all about the weather and here in the UK the weather is unpredictable. Revysol®, the new azole in Revystar® XE removes some of the worry around spray applications and fungicide`s efficacy under adverse weather conditions.
Dr Julie Smith, Principal Crop Pathology Researcher ADAS, investigated the properties of Xemium®, the leading SDHI and the co-formulation partner in Revystar® XE. She said, “Following T2 applications of Xemium® we saw an increase in the size and duration of the healthy green canopy in the period after flowering. As a result, the crop was able to capture more light to drive photosynthesis during grain fill.
We also measured stomatal conductance, the amount of water vapour the leaf surface loses, and found crops which received Xemium® at T1 and T2 have a lower stomatal conductance than untreated crops or crops treated with a non-Xemium® product. Water use efficiency increased significantly when crops were treated with Xemium®, and to put this into context, we converted water use efficiency values into ‘water used per t grain produced’. When the data were meaned across two seasons we found that untreated crops or crops treated with a non-Xemium® product used approximately 380 t water to produce each tonne of grain whilst crops which had received Xemium® at T1 and T2 only used 300 t water. For an average farm producing 8.5 t/ha, that’s a saving of 680 tonnes of water per hectare. If you are on drought prone land that could be very helpful.”
Ben Freer, BASF Business Development Manager said, “Sunshine levels in UK have been higher than usual and this spring was the sunniest on record. However, U.V. light can degrade fungicide performance. We conducted experiments where leaves were sprayed with Revysol® and prothioconazole and then exposed to U.V. radiation, replicating long exposure to sunlight. After 48 hours 37% more Revysol® than prothioconazole remained on the leaves, showing Revysol® offers reliable protection even with high radiation levels.”
Grower Robin Aird from Wiltshire said, “If you get delayed by a week or ten days because its very windy or there is a whole lot of wet weather then the impact on the yield can be immense.”
Dr Smith added “In the real world, you can’t always get on the crop at that perfect timing, we wanted to see how far either side of the traditional T2 timing we could apply Revysol® and still maintain disease control. ”
She undertook independent technical trials to explore Revysol®’s capabilities. “Whilst GS 39 is the optimum timing to apply Revysol®, we found it outperformed prothioconazole at every single application timing – 5, 10 or 15 days before or after the flag leaf spray timing. There was very little difference in Revysol® ’s performance when applied at GS39 or 5 days before or 5 days after. Revysol® consistently delivered both protection and curativity at a range of optimal and suboptimal spray timings. In fact, you can expect the same level of control from Revysol ® applied 14 days after infection as you would expect from a well-timed application of prothioconazole.”
Rain can bring chaos to spraying programmes and Dr Smith carried out trials to test the rainfastness of cereal fungicides using irrigated and non-irrigated wheat plots. She said, “Irrespective of whether rainfall was in intense short bursts, or more prolonged showers, Revysol® was the most rainfast, with very minimal losses occurring, even when heavy rain fell 15 minutes after application.”
Revysol ®’s fast uptake into the leaf where the chemistry is protected explains its rapid rainfastness and also why the fungicide is very stable to UV light and temperature.
Cool temperatures may affect fungicides` performance. Mr Freer added, “Tests have proven that with conventional azoles, the fungicide uptake is limited below 13°C. Revysol® shows an outstanding inner-leaf-uptake, even under cold conditions.These characteristics all mean more opportunities to go spraying without concerns about reduced efficacy.”
Revystar® XE, Revysol® and Xemium® are registered trademarks of BASF. Revystar® XE contains Revysol® and Xemium®. Revysol® contains mefentrifluconazole. Xemium® contains fluxapyroxad. Always read the label and product information before use. For further product information including warning phrases and symbols, you can refer to agricentre.basf.co.uk.