Capitol Corridor
University of California
Capitol Corridor

Posts Tagged: biocontrol

Let's Hear It for Biocontrol, Integrated Pest Management

An assassin bug drills a pest, a spotted cucumber beetle. (Photo by Kathy Keatley Garvey)

Let's hear it for biocontrol. You've seen lady beetles, aka ladybugs, preying on aphids. But have you seen an assassin bug attack a spotted...

An assassin bug drills a pest, a spotted cucumber beetle. (Photo by Kathy Keatley Garvey)
An assassin bug drills a pest, a spotted cucumber beetle. (Photo by Kathy Keatley Garvey)

An assassin bug drills a pest, a spotted cucumber beetle. (Photo by Kathy Keatley Garvey)

A lady beetle, aka ladybug, snares an aphid. (Photo by Kathy Keatley Garvey)
A lady beetle, aka ladybug, snares an aphid. (Photo by Kathy Keatley Garvey)

A lady beetle, aka ladybug, snares an aphid. (Photo by Kathy Keatley Garvey)

A crab spider munches on a stink bug. (Photo by Kathy Keatley Garvey)
A crab spider munches on a stink bug. (Photo by Kathy Keatley Garvey)

A crab spider munches on a stink bug. (Photo by Kathy Keatley Garvey)

A great blue heron engages in a little pest management: it catches a rodent at Bodega Bay. (Photo by Kathy Keatley Garvey)
A great blue heron engages in a little pest management: it catches a rodent at Bodega Bay. (Photo by Kathy Keatley Garvey)

A great blue heron engages in a little pest management: it catches a rodent at Bodega Bay. (Photo by Kathy Keatley Garvey)

The great blue heron gets its prey in position before swallowing it whole. (Photo by Kathy Keatley Garvey)
The great blue heron gets its prey in position before swallowing it whole. (Photo by Kathy Keatley Garvey)

The great blue heron gets its prey in position before swallowing it whole. (Photo by Kathy Keatley Garvey)

Alfalfa YouTube Finalist

YouTube video showing how to identify parasitized caterpillars in alfalfa fields

We are excited to announce that our Alfalfa IPM YouTube video titled, “Identification of parasitized alfalfa caterpillars and armyworms”,...

YouTube video showing how to identify parasitized caterpillars in alfalfa fields
YouTube video showing how to identify parasitized caterpillars in alfalfa fields

Posted on Friday, November 20, 2015 at 4:20 PM
Tags: Alfalfa (51), biocontrol (4), caterpillars (12), natural enemies (1)

Invasive meltdown

Ants can be a huge nuisance in and outside our homes, particularly if you have food lying around. But now, it turns out, they’re unwelcome, too, on citrus trees.  

A year ago, UC Riverside entomologists released Tamarixia, a parasitoid wasp and natural enemy of the Asian citrus psyllid (ACP) imported from Pakistan, into a biocontrol grove in Riverside, Calif. Tamarixia can serve as an excellent biocontrol agent against ACP, a citrus pest first detected in 2008 in Southern California that is capable of spreading citrus greening disease, or Huanglongbing

Tamarixia radiata parasitizing an Asian citrus psyllid nymph in Bell Gardens, Los Angeles County. (Photo: Mark Hoddle, UCR)
Tamarixia’s success starts with a female laying an egg on the underbelly of an ACP nymph. When the egg hatches, the parasitoid larva will scrape away the nymph’s belly, carving out a hole to push through to enter the nymph’s body. Feeding on the contents, the larva eventually excavates the entire nymph, leaving only a shell or husk of the nymph behind.

Female Tamarixia can kill psyllids also by “host-feeding.” They use their ovipositors as daggers to stab psyllid nymphs numerous times until the nymphs start to bleed. As bodily fluids ooze out of the nymph, Tamarixia sucks up this rich protein needed for developing more eggs. 

An excellent way then to control ACP populations! Yes, but only until the ants come marching in. Argentine ants are threatening to disrupt the biocontrol of ACP by battling it out with Tamarixia on citrus branches. While not quite a Vader-Skywalker lightsaber duel on a precarious walkway, an “invasive meltdown” begins when the ants gang up to protect the nymphs.

“ACP nymphs produce a white, sugary waste product called honeydew, a good carbohydrate source for the ants,” explains Mark Hoddle, the director of the Center for Invasive Species Research at UC Riverside, whose research team has released Tamarixia into several Southern California citrus groves. “The ants, therefore, will protect the nymphs from Tamarixia.  We have seen ants chase female Tamarixia off the psyllids, and even catch and eat them!”

Argentine ants tending an infestation of Asian citrus psyllid nymphs. Ants may hamper biological control of ACP by Tamarixia. (Photo: Mark Hoddle, UCR)
Hoddle’s lab is now collecting ACP nymph honeydew to analyze it for sugars so that feeding trials can be conducted on the ants. The research could help the lab produce more effective ant-baits that when left on citrus trees would help decrease the ant population and then reduce, too, the attacks on Tamarixia.

“If you kill off the ants, Tamarixia can play the role of the biocontrol agent it was cast to do on citrus trees,” Hoddle says. “We’re seeing that the ants are impacting Tamarixia in two ways: they are preventing Tamarixia’s establishment in some areas; and, where Tamarixia is already established, the ants are not allowing these parasitoids to reach their full biocontrol potential.”

Posted on Thursday, December 13, 2012 at 8:33 AM

When Contemplating Biocontrol of Pests

Lady beetle, aka ladybug, prowling for aphids on a blanket flower, Gaillardia. (Photo by Kathy Keatley Garvey)

What are the important considerations when contemplating the biological control of pests? That's one of the topics when the Northern California...

Lady beetle, aka ladybug, prowling for aphids on a blanket flower, Gaillardia. (Photo by Kathy Keatley Garvey)
Lady beetle, aka ladybug, prowling for aphids on a blanket flower, Gaillardia. (Photo by Kathy Keatley Garvey)

Lady beetle, aka ladybug, prowling for aphids on a blanket flower, Gaillardia. (Photo by Kathy Keatley Garvey)

Close-up of lady beetle, aka ladybug. (Photo by Kathy Keatley Garvey)
Close-up of lady beetle, aka ladybug. (Photo by Kathy Keatley Garvey)

Close-up of lady beetle, aka ladybug. (Photo by Kathy Keatley Garvey)

Posted on Friday, October 26, 2012 at 9:22 PM
 
E-mail
 
Webmaster Email: kmchurchill@ucanr.edu