Certis fungicide product, Karma (potassiumhydrogen carbonate), has been granted an Extension of Authorisation for MinorUse (EAMU) to allow applications to be made on protected and indoor courgettes,cucumbers and melons for the control of powdery mildew (Sphaerotheca fuliginea andErysiphe oronti).
Derek Hargreaves, independent consultant andtechnical officer of the Cucumber Growers Association explains the value ofthis to growers of these niche crops. Cucumbers, courgettes and melons areparticularly susceptible to mildew. Being short term crops, it is well-knownthat powdery mildew will continuously build throughout the season.
It is common to see three crops of cucumbers grownfrom January to October, and by the time the third crop is planted it is not aquestion of if you will get powdery mildew, but rather when you will get it, soeffective control measures are a necessary routine for growers.
Although courgettes are grown as a successioncrop, it is the same problem we see here. And, once powdery mildew takes holdit can be just a matter of days before widespread infection occurs, he adds.
The fact the Karma has been granted an EAMU forthis purpose will provide growers with added security to continue to use afungicide containing the active ingredient potassium hydrogen carbonate, whichhas the significant advantage of leaving no chemical residue on crops, says MrHargreaves.
Karma is a fully registered plant protectionproduct that in addition to delivering a low residue risk, also benefits from ashort harvest interval as well as having a low environmental impact.
The label states that for use of Karma on indoorand protected courgettes, cucumber and melons, the maximum individual dose is3kg/ha. Growers can make a maximum of eight applications per crop per year,providing the maximum total dose of 24kg/ha/crop isnt exceeded.