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www.goodfruit.com Good Fruit Grower OCTOBER 2016 39 product, almost halved both blossom blight to 10 percent and shoot blight incidence to 3 percent. Similarly, add- ing Rampart (mono- and di-potassium salts of phosphorous acid) to Serenade (Bacillus subtilis) cut blossom blight by two-thirds to 3 percent and increased shoot blight incidence slightly to 3 percent. The next best contender was a pro- gram of Apogee and Double Nickel (Bacillus amyloliquefaciens), a biological control product, at full bloom. Apogee thickens plant cell walls, slow- ing the invasion of infections occurring later at bloom. Bacteria in Double Nickel produce antimicrobial metabolites to reduce the populations on the stigmatic surface. Though not as effective at fi re blight control as antibiotics, they still kept blos- som blight down to less than 30 percent and shoot blight to 5 percent, Zhao said. Apogee in young blocks Typically growers are hesitant to use Apogee on younger trees because they don't want to limit their growth. That's why Zhao and Cox also tested its use in young stock. "We wanted to see if they would control blossom and shoot blight without using antibiotics and negatively affecting growth," Zhao said. They applied Apogee in both early and late treatments. The early treatment — done at pink — was a combined appli- cation of Apogee and Double Nickel. The late treatment, Apogee by itself, was done at petal fall. They applied Apogee in both low and high concentrations in the early treat- ment and in high concentration only in the late treatment. The low concentration treatment was 3 ounces per 100 gallons, while the high concentration treatment was 6 ounces per 100 gallons. Double Nickel was applied at one rate, 32 fl uid ounces per acre. Early Apogee treatments kept both blossom and shoot blight incidence below 10 percent. Late treatments took blossom shoot incidence down to 12 percent and shoot blight to less than 5 percent. Apogee, in both low and high concen- trations and early and late applications, did not negatively impact fruit size. "All the treatments showed good increases in fruit size," she said. Two of the trial products — strepto- mycin and late Apogee treatments — lived up to grower concerns, stunting primary shoot growth. Overall primary shoot length averaged 98 inches. Streptomycin-treated tree primary shoots reached only 78 inches and late Apogee treatments produced 70-inch primary shoots. • ONLINE Look for more coverage of the 2016 IFTA New York Study Tour at goodfruit.com and in future issues. THANK YOU GOLFERS AND SPONSORS 23rd Annual WSTFA Memorial Scholarship Golf Tournament The tournament, held August 2 at the Highlander Golf Course in East Wenatchee was another success! 2016 FIRST PLACE TEAMS WOMEN'S DIVISION Stemilt Growers: Wendy Everhart, Mandy Hanko, Lisa Myers, Chris Shannon MEN'S DIVISION Wilbur-Ellis: Tim Baity, Brian Jones, David Lerma, Steve Rawley 2016 HEADLINE TOURNAMENT SPONSORS To learn more about the Washington State Tree Fruit Association Memorial Golf Tournament contact WSTFA: 105 S 18th St #116 Yakima, WA 98901 Phone: 509-452-8555 Website: www.wstfa.org