Thrips vs. Mites: an Epic Fight

This is a guest blog by Post-Doctoral Researcher Sarah Jandricic, who specializes in Greenhouse Entomology. You can read more about our greenhouse research program here.

Western flower thrips and damage on petunia leaf. Photo: SD Frank

The fight is about to begin! In one corner of the ring we have the number one pest of greenhouse crops in the world: the western flower thrips. This nasty little insect might look like a lightweight, but it’s in the heavy-weight class when it comes to damage. By sucking out the contents of individual plant cells, thrips cause a scratched, or “silvered” appearance to leaves and flower petals. Adding insult to injury, thrips can also transmit lethal plant viruses like Impatiens Necrotic Spot Virus.

In the other corner, we have the fan favorite – the predatory mite! Cucumeris are notorious for killing and eating 1st instar thrips (the life stage that hatches directly out the egg), and are sold commercially for control of thrips in greenhouses. Adult mites can eat 4 to 10 of these 1st instar thrips each day. But Cucumeris has yet to face its current opponent: the older and larger 2nd instar Western flower thrips.

Ding Ding Ding! The fight has begun!

The video of our fight (Sarah Jandricic and Matt Bertone, NCSU), shows Cucumeris making repeated attacks to the flank of Western flower thrips! But what’s this? The thrips is using its abdomen to land repeated blows to the head and body of Cucumeris! Despite a valiant effort from our plucky predator, it just can’t seem to find an opening. After several rounds, it’s clear that our 2nd instar Western flower thrips has won the fight.

But hold on, folks. Breaking news is coming from the post-fight interview…

It turns out that defending itself from the mite has cost our 2nd instar thrips dearly. Thrips engaging in this sort of battle spend less time feeding, cause less damage to plants, and ultimately are less successful in completing development into adults.

So, the story is clearly not over. The Frank Lab at NCSU is currently investigating ways to capitalize on effects of mite “intimidation” on 2nd instar thrips for better control of this pest in greenhouse crops.

Stay tuned for more updates on this big battle occurring in the tiny world of insects!

2017-06-29T12:27:43-04:00 July 24th, 2014|Categories: Greenhouse IPM, Lab Happenings, Natural Enemies|Tags: , , , , |

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