Issue link: http://read.dmtmag.com/i/459886
www.goodfruit.com GOOD FRUIT GROWER FEBRUARY 15, 2015 15 © 2015, Trécé Inc., Adair, OK USA • TRECE, PHEROCON and CIDETRAK are registered trademarks of Trece, Inc., Adair, OK USA TRE-0691, 1/15 PLEASE: ALWAYS READ THE LABEL 32 MESOS/ACRE = SUPERIOR MATING DISRUPTION The ONLY Mating Disruption System for both MALE… and FEMALE Codling Moth INSEC T PHEROMONE & KAIROMONE SYSTEMS INCORPORATED ® Your Edge – And Ours – Is Knowledge. CIDETRAK ® CMDA COMBO ™ MESO ™ contains a unique combination of Codling Moth pheromone AND a patented male AND female behavior modifying kairomone called DA. Designed to deliver long-lasting performance with remarkably fast application at 32 MESOS/ACRE. • What it does: Disrupts oviposition, reduces mating, maintains higher virginity and lowers damage. • How to use it: Ready-to-use package, ready-to-hang dispensers. • Longevity: Long-lasting full season performance. CIDETRAK ® CMDA COMBO ™ MESO ™ dispenser in use at 32 MESOS/ACRE. T R E C E T E C H N O L O G Y ´ ´ WSDA ORGANICALLY APPROVED! Contact your local supplier and order now. Visit our website: www.trece.com or call 1- 866 -785-1313. infection on fruit naturally exposed (not covered) in the orchard at 80 days post bloom. Probst found that all timings of Sweetheart and Bing cherries, inoculated with 5,000 spores per milliliter, resulted in some fruit infection at harvest. The one-year susceptibility study raises further questions. For exam- ple, how many spores are needed to cause an infection? How long do spores survive in natural settings without covers? Literature has shown powdery mildew spores generally survive a couple of days, says Probst. The study also reinforces the need for an effective pest management strategy, said Probst. Spraying cherry orchards with fungicides after harvest may be a way to knock down spore concentrations for the following sea- son. Grove has been working on postharvest fungicide sprays as a way to reduce spore concentrations on post- harvest foliage that otherwise can overwinter and trigger infection the following spring. Spore concentration A separate one-year trial looked at fi ve concentration levels of spores (10,000, 5,000, 1,000, 500, and 100 per ml) to learn the threshold needed to cause infection at different developmental stages. Fruit were covered with the special bags and inoculated with different spore con- centrations at three different dates (May 29, June 12, and June 26) to represent early, mid, and late timing of the season. "It took fruit inoculated with 500 spores in early sea- son to result in 26 percent infection of fruit at harvest," Probst said. "But fruit late in the season, inoculated with 500 spores, had 76 percent of fruit infected at harvest." She explained this shows that disease development is a function of both growth stage and inoculum concentra- tion. "The conidial concentration needed to cause signif- icant disease at harvest is dependent on developmental age of fruit. The younger the fruit, the more spores are needed." Research funding from the Washington Tree Fruit Research Commission will allow WSU to develop molecular technology to learn more about spore viabil- ity. Future research will also look at impact from spore density and management practices. • COURTESY OF CLAUDIA PROBST %DJVPDGHRI¼QHPHVKQ\ORQPDWHULDOZHUHXVHGLQFKHUU\ orchards to keep inoculated spores inside the bags and airborne spores out of the bags. That allowed researchers to know when fruit were infected.