A new fungicide is scheduled to be registered this year in California that will provide not only control of at least eight almond diseases, but will add to the all important resistance management toolbox.
According to University of California, Riverside, plant pathologist Jim Adaskaveg, Quash fungicide from Valent is a “robust” fungicide in the Sterol Biosynthesis Inhibitors (SBI) class.
Adaskaveg told pest control advisers (PCAs) at a Valent-sponsored meeting last fall that Quash is one of the most active fungicides in its class and rotating with it will ward off disease resistance in almonds.
Alternaria leaf spot is a growing problem in California almonds, compounded by recent verified resistance to strobilurn fungicides in the Butte County area, said the UC plant pathologist.
Registration of Quash, which is expected this year in California, according to Adaskaveg, will combat this Alternaria resistance. It is already federally registered.
Adaskaveg said Alternaria control with Quash is comparable to existing materials and will be valuable in a resistance management program using SBIs.
The new fungicide, primarily a bloom spray, also is active against anthracnose, brown rot, shot hole, jacket rot, scab and other almond diseases.
California registration for disease control in stone fruit also is expected this year.
It has a 25-day pre-harvest interval for almonds and 14 days for stone fruit.
Where diseases are major issues in almonds, the rapidly spreading vine mealy has emerged as the No. 1 nemesis of California grape growers. It has spread rapidly from Coachella Valley to Mendocino County.
Valent’s new generation neonicotinoid insecticide Clutch will soon have a soil applied label to allow growers to apply it through a drip system for systemic distribution through the plant, according to Monte Peckinpah, Valent sales representative. Clutch now has federal and state foliar-applied labels and a soil applied label is expected this spring.
Carlos Granadino, Clutch product development manager, says the Clutch drip-applied/systemic label will put the product in the first 8 inches of the soil profile when applied at the 6-ounce rate in April-May. The product has a low water solubility which means less leaching potential.
It will have a pre-harvest interval of 30 days and a 12-hour re-entry period.
Valent’s new pre-emergence residual herbicide, Chateau, has received expanded California crop registrations including tree nut crops and alfalfa, PCAs were told.
A new mode of action herbicide (PPO inhibitor), Pat Clay, Arizona Valent representative, says Chateau provides excellent control of broadleaf weeds and annual grasses in alfalfa.
It controls 60 weeds, according to Clay, including groundsel, pigweed and lambsquarter.
Mick Canavari, UC Cooperative Extension farm advisor and county director in San Joaquin County, has been conducting Chateau trials on alfalfa since 2002.
Alfalfa is the largest field crop in California with 1.3 million acres. Most of the alfalfa goes to dairies where the difference between weed-free and weedy hay represented as much as $90 per ton in recent high prices for the forage crop.
Canavari says Chateau is an effective herbicide, often enhanced by tank mixing it with other products like Gramoxone and Velpar.
With its 25-day pre-harvest interval, Canavari says Chateau may have a fit in-season to control summer grasses. However, it may burn back the alfalfa for about 14 days.