Tomato: use parasitic wasps until Macrolophus is ready

The predatory bug Macrolophus pygmaeus is popular in the fight against whitefly. But it takes a while before this beneficial is at full fighting strength. Introducing parasitic wasps can prevent problems due to early arrival of whitefly.

If you are familiar with using the predatory bug Macrolophus pygmaeus in the fight against whitefly, you know that sometimes it can take quite some time before the population of this beneficial reaches fighting strength. That’s also why we advised you to introduce Macrolophus as early as possible during spring.

But even if you’re early, whitefly can still arrive before the Macrolophus population is ready. “We therefore advise you to use the Encarsia formosa wasp to fight early whitefly, as a sidekick of Macrolophus,” says Wesley Akkermans, sustainable crop management specialist at Biobest. “This parasitic wasp is a good choice in tomato. It should be introduced in small amounts right now, just before growers expect the whitefly to arrive.”

It’s better if you introduce Encarsia even before you spot the first whitefly in your crops. “These pests insects tend to be present before you detect them,” knows Wesley from his experience. “I’m afraid that if you apply the parasitic wasps only after spotting whitefly, the risk of running into difficulties is quite high.”

Wesley advises small amounts of Encarsia. “Minimally 0,5 to 1,0 wasps per m2, every 1 or 2 weeks, should be sufficient.” If temperature is already increasing, you can decide to switch to Eretmix, a mixture of both Encarsia formosa and Eretmocerus eremicus.

For more advice contact your Biobest adviser or register on www.biobestgroup.com to get in contact with us straight away.