Posts Tagged: Tamarixia radiata
Biological control of Asian citrus psyllid in California
Research by Dr. Mark Hoddle, University of California, Riverside Dr. Mark Hoddle, a research...
Ants- they keep coming back
Many growers seem like they will never win the never ending battle with ants, they're everywhere! Conversely, ants travel through soil and help loosen it improving quality, allowing water, air, and nutrients to flow freely through it. They also decompose dead plant and animal matter and can even feed on other insects. However, ants sometimes chew crop twigs and tender bark, damage irrigation tubing, and can annoy and harm workers. You can find ants traveling alongside your trees, the ground, or irrigation lines and build their nests underground.
The southern fire ant (Figure 2.) is light reddish brown with a black abdomen. Active in the morning and early evening and do not trail. May swarm out of nests if disturbed and can inflict painful stings.
Native gray ants (Figure 3.) are gray and considerably larger than the other two species. They nest in topsoil or under rocks and debris and move in irregular patterns. In contrast to Argentine and fire ants, the native gray ant is solitary and its importance in disrupting biological control is often underestimated. Red imported fire ant is new to California and can make large, dome-shaped mounds. They feed on almost any plant or animal material.
Avocados & Citrus
Ants are pests primarily because they disrupt biological control of other pests, especially that of the Tamarixia radiata, which is a natural predator for the Asian Citrus Psyllid. Ants are also a big problem in young trees causing trunk damage as well as feed on honeydew excreted by various soft scales, mealybugs, cottony cushion scales, whiteflies, and aphids. As part of this relationship, they also protect these insects from their natural enemies, thus interrupting biological control of the honeydew-producing pests. In the process of keeping most natural enemies away, they also protect other pests, such as California red scale, that profit from the lack of natural enemies. Argentine and native gray ants are the most common ant species that aggressively protect pest insects. In addition, Argentine ants and red imported fire ants can plug up irrigation sprinklers. Red imported fire ants directly damage plants by chewing twigs and tender bark of newly planted trees; they also sting people working in the orchard and may cause allergic reactions and sometimes trips to the emergency room.
For more information on ants in avocados, please visit the UC IPM website:
http://www.ipm.ucdavis.edu/PMG/r8301311.html.
For more information on ants in citrus, please visit the UC IPM website:
http://www.ipm.ucdavis.edu/PMG/r107300211.html.
Management
Ant management requires diligent efforts and the combined use of mechanical, cultural, sanitation, and often chemical control methods. Ant populations peak in mid-summer through early fall, therefore the best time to bait is late winter to early spring when ant numbers are relatively low. Bait effectiveness varies with ant species, availability of alternative food, active ingredient, type of bait, and the time of year. To determine which bait to use, offer a small quantity of each of several baits and observe which is preferred by the ants.
For information on ants in general, please visit the UC IPM website:
http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7411.html.
Hansen Fund Dollars at Work!
The expanding presence of the Asian citrus psyllid (ACP) threatens the California citrus...
Salmon suffering because of scant rain
Biologists are concerned about any harm done to coho, a fish which is being coaxed back from the brink of extinction but still numbers only in the hundreds.
“There is so much invested in bringing these coho back, from the hatchery program to the restoration work in Dry Creek to the monitoring,” said Mariska Obedzinski, who is monitoring the coho recovery program for the UC Cooperative Extension. “For someone to go out and accidentally catch one when they are in the river, when they could kill or harm them, it is discouraging.”
Corps of Engineers leads coalition effort to save coho salmon
JC Delgadillo, www.army.mil, The U.S. Army
In the winter of 2011, biologists funded by the U.S. Army Corps of Engineers counted a record number of wild juvenile coho salmon in the downstream portions of the Russian River system in western Sonoma County. The project is conducted in collaboration with NOAA's National Marine Fisheries Service, experts at the University of California Cooperative Extension and the Sonoma County Water Agency.
"It's quite the group we have working together," said supervisory fisheries biologist Ben White of the U.S. Army Corps of Engineers. "You've got the best scientific knowledge in the region and people with a deep passion for coho recovery. You've got leaders among their peers working this issue, and I'm proud to be a part of it. You wouldn't be in this field if you didn't care about these fish, and everybody involved wants to see them recover."
Scientists release wasps to control citrus pest
Jeff Spurrier, L.A. at Home blog, Los Angeles Times
On Jan. 6, UC Riverside bio-control specialist Mark Hoddle released 300 tiny parasitic wasps from Pakistan in the L.A. County cities of Pico Rivera, Bell Gardens and South Gate to feed on the Asian citrus psyllid.
The article mentioned that curry leaf, an herb used in Indian cuisine, can be a host for the Asian citrus psyllid.
“If someone has curry leaf and are in the L.A. area, we’d be interested in looking at their plants and maybe using them for our parasite release,” Hoddle said.
The reality of extreme weather, Part 1
Lynne Friedmann, La Jolla Light
It’s not your imagination. Weather is becoming more “extreme,” leading to prolonged heat waves, heavier precipitation, severe flooding, more powerful hurricanes, and intense snowstorms.
Especially problematic is a trend toward long heat waves, during which morality increases, and more humid heat waves resulting in higher nighttime temperatures.
Evening “chill hours” in which the temperature drops below 450º F are also critical for agriculture.
“There are three million acres of fruit orchards with chilling requirements,” said Louise Jackson, UC Cooperative Extension plant physiology specialist. “Increasing humid heat also impacts red wine grape yields.”
California Report features UCCE biocontrol scientist
Reporter Rachael Myrow told listeners the release of natural enemies on Friday is the first major release in a major urban area, and then allowed Hoddle to explain the developments and their implications.
For more on Tamarixia radiata, see the UC ANR press release.
Myrow also posted a story on newsfix, KQED's Bay Area news blog.