- Author: Alejandro Del Pozo-Valdivia
Diamondback moth adults have been actively flying across the Salinas Valley these winter months, based on our area-wide monitoring program. There were a couple of locations where we recorded 'zero' captures during January. It looks like low temperatures in the Valley just slowed down this moth development. At this point, it will be difficult to propose that there was an overwintering generation this past winter. Specially in the Castroville area, where there has never been a 'zero' capture from our two traps. Having an overwintering generation would have represented 'zero' captures from all or most of our pheromone traps across the Valley.
We continue the effort to validate automated pheromone traps. In partnership with AgCeleration and TrapView, we are testing in the field a new prototype (Fig. 1). So far, there is no significant difference on the weekly captures between this new automated trap when compared to a typical cardboard pheromone trap. These automated traps provide real-time information on the number of diamondback moth males captured in a daily based. This type of information could ultimately help to understand the trends of the adults moving across the farmscape, strengthening an IPM program in cole crops.
Daily captures of diamondback moth male adults indicate that the highest populations are currently located in the Castroville area. On average, we have captured 12 males per day since February 11th (Fig. 2.). Most of the fluctuation on number of captured adults might have been mediated by air temperatures. The current trend shows that adult captures are going down. It is likely that large populations of this pest were able to go through a generation in the Castroville area using crop, weed host plants, and crop residues. It is important to recognize that:
1) Castroville area continues to be a hot spot with the largest diamondback moth population across the Salinas Valley.
2) Promptly scouting of blocks with cole crops will help to early detect the presence of economically relevant numbers of caterpillars.
3) Manage weeds, specially at the surrounding areas of established blocks, will reduce the overall population.
4) Promptly elimination of cole crop residues from previous plantings will reduce the overall population.
5) Rotate the use of insecticides will reduce the possibility to develop insecticide resistance.
6) Use of adjuvants/stickers will reduce the possibility of washing away any insecticide spray onto waxy cole crop leaves.
If you would like to learn more about the current status of diamondback moth in the Salinas Valley, please contact Alejandro Del-Pozo at adelpozo@ucanr.edu or call 831-759-7359.
- Author: Michael D Cahn
The California Plant and Soil Conference will be held in Fresno CA at the DoubleTree Hotel and Convention Center on February 4-5, 2020. This is a very comprehensive conference with talks from speakers invited from industry, government agencies, and universities. Topics this year will include cover crop management, nitrogen management, organic amendments, pest management, water quality regulations, pesticide mitigation in runoff and more. Both CCA and DPR educational hours are available. For more information please visit the California Chapter of Agronomy Society of America or to see the full agenda go to calasa.ucdavis.edu/Agenda/
- Author: Michael D Cahn
- Author: Richard Smith
This year we will cover a wide range of topics related to water and nutrient management, including food safety, pesticide toxicity, organic nitrogen management, drip germination, weather-based irrigation scheduling, as well as ground water management in the Salinas Valley. Please come and participate and enjoy a free lunch! As always, registration is free.
Monterey County Agricultural Center
1432 Abbott Street, Salinas, CA
Tuesday, February 18
7:45 a.m. to 12:30 p.m.
7:45 Registration (free)
8:00 Best management practices for mitigating pesticides in run-off
Bryn Phillips, Toxicologist, UCD Granite Canyon Laboratory
8:30 Does evapotranspiration (ET) work?
Michael Cahn, Irrigation and Water Resources Advisor, UC Cooperative Extension
9:00 Effect of drip germination on topical N fertilizer applications
Richard Smith and Michael Cahn, UC Cooperative Extension
9:30 Using weather-based irrigation scheduling for optimizing cauliflower production
Lee Johnson, Senior Research Scientist, NASA Ames Research Center-CSUMB
10:00 Break
10:30 A minus R: Implications and challenges for Central Coast farming.
Michael Cahn, Irrigation and Water Resources Advisor, UC Cooperative Extension
11:00 Treatment of reservoir and tail water for protecting food safety
Channah Rock, Associate Professor, University of Arizona
11:30 Organic fertilization of vegetables
Richard Smith, Vegetable and Weed Science Advisor, UC Cooperative Extension
12:00 Update on Salinas Valley ground water management
Gary Petersen, General Manager, Salinas Valley Groundwater Sustainability Agency
12:30 Pizza Lunch
CCA & DPR continuing education credits have been requested
For more information, contact Lennis Arriaga @ 831-759-7353, email: larriaga@ucanr.edu
The University of California prohibits discrimination or harassment of any person in any of its programs or activities. (Complete nondiscrimination policy statement can be found at http://ucanr.org/sites/anrstaff/files/107734.doc). Inquiries regarding the University's equal employment opportunity policies may be directed to Affirmative Action Contact and Title IX Officer, University of California, Agriculture and Natural Resources, 2801 2nd Street, Davis, CA 95618, (530) 750-1397; titleixdiscrimination@ucanr.edu.
- Author: Alejandro Del Pozo-Valdivia
- Author: Alejandro Del Pozo-Valdivia
On Wednesday October 9th, a Brussels sprout plant sample was submitted to our Entomology laboratory for insect identification.
At the naked eye, we observed some webbing and specks on the leaf (See Fig. 1).
Fig. 1. Leaf of Brussels sprout showing some webbing and 'specks'. Affected areas are highlighted with the yellow circles.
Under magnification, we were able to see eggs, nymphs and adults of the two spotted spider mite (TSSM), Tetranychus urticae (See Fig. 2). Adults of these specimens have the two black spots on the lateral sides of the anterior end of the podosoma, the area located below their mouth parts.
Fig. 2. Eggs, nymphs and adults of two spotted spider mites on the leaf of Brussels sprout.
TSSM is one of the most polyphagous mites, having several host plants around the world. Females disperse by putting silk strands right after mating and before producing eggs. Dispersing females climb to the top of the plant and specimens are carried out by the wind. This phenomenon called ballooning, aids mites to float through the air and disperse longer distances to reach favorable host plants.
It is highly advised that Brussels sprout growers and PCAs walking this crop, pay close attention to leaves within the canopy to potentially identify the presence of TSSW in this crop.
If you believe you may have TSSM in your Brussels sprouts, please send us a plant sample at 1432 Abbott St. in Salinas for confirming identification (free service), or call us at 831-759-7359 to obtain additional information on this pest.
