IN YOUR ORCHARD
Scab ( Venturia carpophila ; formerly Cladosporium carpophilum or Fusicladium carpophilum ) was effectively controlled with the strobilurin or QoI (QoI-quinone outside inhibitor) fungicides (Abound, Gem), but resistance to these fungicides has developed and we now recommend not using FRAC Group 11 fungicides exclusively unless in pre-mixtures or tank mixtures and in orchards without known resistance. Dr. Adaskaveg has developed a three-spray strategy for scab control that includes a delayed dormant application of copper-oil or chlorothalonil-oil, a two-week after petal fall spray that includes chlorothalonil (Echo, Bravo, Equus; FRAC M5), and a five-week
after petal fall spray that includes Captan (FRAC M4), Ziram (FRAC M3), or pre-mixtures of DMI (FRAC 3), SDHI (FRAC 7), or QoI (FRAC 11) fungicides. Ph-D (FRAC 19) can also be used in tank mixtures. Recent work by Dr. Adaskaveg has also shown that delayed dormant applications of chlorothalonil and oil are even better than copper and oil at reducing scab inoculum well into the spring season. This will reduce in-season sprays and, if Alternaria leaf spot is also a problem, the in-season sprays for scab and Alternaria will be aligned (late spring). Venturia (i.e., Fusicladium ) causes greasy dark spots on fruit, leaves, and green shoots. The shoot lesions are the overwintering sites for the fungus and the source of new spores in the spring. The disease causes no apparent damage to the fruit, but leaves may fall prematurely. Rust ( Tranzschelia discolor ) can also cause defoliation. Both rust and scab are favored by high humidity and are usually worse in years with late spring rains. Irrigation practices that create humid orchard conditions for long periods of time favor both diseases. Like scab, rust
0
0
MO --POLLEN-- Leading the industry in commercial pollination ofnut and tree fruit crops. Committed to high-qualitypollen, purity, viability, and certainty ofpollen alleles.
0
0
0
Contact us today to see how we can serve your operation. FIRMAN -- lenN 111m • 509-452-8063 I 800-322-8852 FirmanPollen.com
A L M O N D F A C T S •
4 2
Made with FlippingBook - Online Brochure Maker