Successful sprout inhibition starts with Crown MH

Arable farmer Henk van Sluijs from Westkapelle has been fitting for years in a row Crown M.H in his potato chips. This lays the foundation for successful sprout inhibition during storage. In addition, it drastically reduces potato storage in successive crops and Phytophthora gains less foothold.

It is early June when arable farmer Henk van Sluijs and cultivation advisor Leo Zandee of CZAV inspect 3,5 hectares of seed onions. The plot withstood the heavy thunderstorm with more than 62 millimeters of precipitation in the previous week, although it remains to be seen how the growth will continue. Herbicides had already done their job before that. Very good in fact, the gentlemen conclude with satisfaction.

Less work
Here and there only some potato storage is visible. It will soon be easy to get rid of with the glyphosate stick. "Drop it and they'll be gone in no time," says Van Sluijs. "The few storage plants you see now are worth nothing. It would look very different if I did not have any Crown M.H had applied. That would have given me days of extra storage control work. Now it's beeped within one day."

Up to 70% storage reduction
The Zeeland grower has been using the product as a sprout regulator for his French fries potatoes for years. "You spray it during the growing season and then the tubers already have a sprout inhibitor when they are stored," explains Zandee. "And because you apply it during cultivation, the sprout inhibitor is also in the tubers that remain on the field. In subsequent crops, that means much less potato storage. The effect varies slightly per variety, but Crown MH can achieve a storage reduction of up to 70%."

Lower disease and virus pressure
Less potato storage also means lower Phytophthora pressure, the cultivation advisor concludes. "And a lower virus pressure, which is nice for the seed potato growers in the area." Van Sluijs also sees practical advantages. "It is a liquid agent and that is easy to use. In addition, it mixes well in the tank and foams less than with granulate.

Pay attention to application time
What you should pay attention to for optimal effect is the application time. "For a good absorption and distribution of the active ingredient maleic hydrazide to the tubers, the crop must still be active," says Van Sluijs. "After flowering, the growth of the foliage shifts to the tuber. When the active foliage growth is over and most tubers are in the 30 to 35 millimeter range, you can in principle start spraying." First estimate when the haulm killing will take place. Between spraying with Crown M.H and the haulm kill should be at least 3 weeks, preferably 5. Timing can sometimes be difficult in extremely dry, wet or windy weather. "It can be very windy on the Zeeland coast, but I was always able to carry out the treatment at the right time."

Rest in the tubers
The arable farmer from Westkapelle has a lot of experience with Crown MH. He used it in Victoria for years on end. This year he is using the germ regulator on 11 hectares of Lady Anna, intended for Nedato in Oud-Beijerland. He is very pleased with the sprout inhibition. "You start the storage with rest in the tubers. This is a great advantage, especially in germinating years."

Zandee mentions one last argument for field treatment: "Most new germ inhibitors for room treatment can only be used on a dry product. With Crown M.H basically you can postpone the first treatment long enough. The potatoes are given plenty of time to dry and heal their wounds."