- Author: Vonny M. Barlow
Basic background and biology of the blue alfalfa aphid:
The blue alfalfa aphid (Acyrthosiphon kondoi Shinji) was first identified by entomologists in the spring of 1975 in the Imperial Valley of California. Since then it has become widespread throughout the state and has become established in Arizona, Nevada, New Mexico, and as far east as Kansas and Oklahoma. Both adults and nymphs feed on photosynthetic fluids from the leaves and stems of the alfalfa plant. Low to moderate populations of blue alfalfa aphid (BAA) may cause little to no visible yellowing of plants. Blue alfalfa aphid feed in the new growth, at the tips and young leaves. After prolonged feeding, leaves will eventually turn yellow,...
- Author: Vonny M. Barlow
- Author: Peter B. Goodell
- Author: Larry Godfrey
The blue alfalfa aphid, Acyrthosiphon kondoi Shinji was first identified by entomologists in the spring of 1975 in the Imperial Valley of California. Since then it has become widespread throughout the state and has become established in Arizona, Nevada, New Mexico, and as far east as Kansas and Oklahoma. Both adults and nymphs feed on photosynthetic fluids from the leaves and stems of the alfalfa plant. Low to moderate populations of blue alfalfa aphid may cause little to no visible yellowing of plants. Blue alfalfa aphid feed in the new growth, at the tips and young leaves. After prolonged feeding, leaves will eventually turn yellow, starting at the veins, leaves will curl and wilt, and turn necrotic...
- Author: Vonny M. Barlow
- Author: Eric T. Natwick
Of all of the insecticides evaluated against blue alfalfa aphid (BAA) by Eric Natwick of Imperial County, almost every insecticide applied to alfalfa this spring gave initial knockdown of BAA. Blue alfalfa aphid populations resurged in 7-10 days. Treatments giving 70–75% control (reported by PCA’s) were combinations of a pyrethroid with an organophosphate.
Possible factors for our BAA issue:
- High initial aphid populations
- Smaller than expected populations of predators and parasites; particularly the seven-spotted lady beetle
May be weather related or pesticide...
- Author: Vonny M. Barlow
When: Friday, May 17th, 2013, 12:00 – 2 PM
Contact: Vonny Barlow,Vmbarlow@ucdavis.edu
Where:
- Friday May 17, Riverside County Administration Building Lunch Room, 290 N. Broadway, Blythe CA
What: Informational meeting on Blue Alfalfa Aphid outbreak and future action
Who: PCAs, alfalfa producers, crop protection industry
Why: Severe outbreaks of Blue Alfalfa Aphid have been reported in the San Joaquin Valley as well as other locations in CA. Large populations have been difficult to manage in...
