Koppert advises taking precautionary measures now. "Spring is coming slowly but surely. This is why you should start now with counting catching strips, so that you know whether there is already white fly in your greenhouse and to what extent. But beware: the tobacco white fly (Bemisia tabacii) is often strongly spread through crops. Catching strips can therefore give a hazy or incomplete view. You should therefore make sure that there is sufficient scouting among the crops. Based on the total image you can then determine what wasps to use and in what amounts."
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"At the same time ensure a strong population of Macrolophus pygmaeus (Mirical). Maintain 6 per plant as a borderline. Continue to feed the predatory bug well so that the population remains at the desired level. Also hang up Horiver Rollertraps, as you can catch white fly with this as well."
For more information:
Koppert Biological Systems
Tel: 0031 (0) 10-5140444
Fax: 0031 (0) 10-5115203