Brought to you by BASF
'Fungicide Scala also works against head rot'
In addition to the already known good effect against leaf spot disease and stemphylium, Scala also appears to be effective against head rot. Provided that it is sprayed early, the fungicide can compete with a widely used reference agent. “Scala deserves a more prominent place in fungicide schedules.”
"You see the head rot very early this year in storage," says Bert Westhoff. "That is an important difference with other seasons. And the consequences are not small. We see in our research that two-thirds of the tare is attributable to the head rot." According to the product advisor, head rot infections often occur earlier than practice thinks. "Koprot only infects dying tissue; the dying oldest leaves can also be an entry point. Upright dying crops, such as this year due to downy mildew, makes it a lot easier for the fungus to reach the bulb afterwards.
Good effect on head rot
Westhoff did not have to worry about the infection on the test field in Dronten. The test of which he showed the results last week during an afternoon viewing for the GBM trade was artificially infected. "And that was successful," he laughs. "On the untreated object, more than 30% of the plants were affected by head rot." In the object where Scala showed the good head rot effect, the fungicide was applied early. Westhoff: "We think that Scala can be an excellent partner for Zorvec spraying. So start applying in the first half of the spraying season. At the moment, Scala is often only used in the second half of the season, but if you want to take advantage because of the head rot effect, you have to start with Scala earlier."
Scala in more spray schedules
The trial in Dronten showed that Scala worked slightly better against head rot than a commonly used downy mildew agent. "Based on the head rot, Scala certainly deserves a place early in the schedule," said Westhoff. Incidentally, Signum was the drug with the best head rot effect in the trial, but in many schemes that drug has considerable 'competition' from downy mildew products that also contain strobilurins. "Due to the development of resistance, a maximum of half of the fungicide sprayings in onions can be carried out with a strobilurin," explains Westhoff. "In practice, a remedy against downy mildew is often chosen. But it is therefore beneficial that there is now a good alternative against head rot without strobilurin. Scala contains pyrimethanil and that substance comes from a different resistance group. That makes Scala a perfect choice in any case. In addition, Scala has a curative and preventive effect and also has a local-systemic effect."
Westhoff expects Scala to appear in more spray schedules in 2022. "Many mancozeb-containing agents are disappearing and we have now demonstrated the head rot effect of Scala. And the usability of Scala is also given a significant boost due to the gentleness of the crop."
