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128 WINES&VINES January 2018 GRAPEGROWING PRACTICAL WINERY & VINEYARD was achieved. In the two years when Mustang Maxx was the insecticide used, it provided sig- nificant control (48% average) when applied alone, whereas antimicrobial treatments applied alone on this same pre-symptom schedule provided only 28% control when averaged for all materials across the three trial years. For growers deciding whether to apply only an insec- ticide or antimicrobial product, the insecticide appears to be the more important component of the mix. Also noteworthy is that initi- ating antimicrobial sprays before the onset of symptoms was more effective than using a limited number of applications after symptoms appeared. The experi- mental design did not allow ex- a m i n a t i o n o f t h e e f f e c t o f insecticide applications alone if initiated after development of disease symptoms. Training system effects In a commercial vineyard of Vitis interspecific hybrid Vi- gnoles in Branchport, N.Y., one block was divided into 14 vine rows trained in a vertical shoot position (VSP) system and 14 vine rows trained to a high-wire cordon (HW) system. Signifi- cant sour rot severity was ob- served in the vineyard block in previous years. The goal was to study whether or not the train- ing system had a significant ef- fect on disease development. In 2014-16, one vine was se- lected in each of 20 rows (10 in the VSP section and 10 in the HW section of the block). Following the first sighting of sour rot symptoms in the vineyard, dis- ease ratings were made every three to four days until harvest. In all three years of the study, there was significantly more sour rot at harvest in vines trained to the HW trellis system than the VSP system. In 2014, for example, sour rot severity increased from 21% to 35% in the HW system and from 13% to 18% in the VSP system in the final seven days before harvest (see "Effect of Training System o n S o u r Ro t D e v e l o p m e n t , " above). This study served not only to examine the differences be- tween training systems but also to document the rapid progres- sion of disease severity as it increased steadily in both train- ing systems over the final one to two weeks before harvest. Sour rot severity measured in a commercial vineyard block of Vitis interspe- cific hybrid Vignoles in Branchport, N.Y., during the final seven days before harvest in 2014, as a function of the two training systems in the block, high- wire cordon (HW) and vertical shoot positioning (VSP). For each assessment date, means not followed by a common letter are statistically different (P = 0.05). EFFECT OF TRAINING SYSTEM ON SOUR ROT DEVELOPMENT 45 40 35 30 25 20 15 10 5 0 Cluster area diseased (%) Harvest - Seven days Harvest - Three days Harvest n HW n VSP A B A B A B SUBSCRIBE ONLINE & SAVE! winesandvines.com/subscribe Print + Digital Magazine 12 monthly issues a year for $28 winesandvines.com/subscribe WINESANDVINES.COM JANUARY 2017 Unified Wine & Grape Symposium Issue INSIGHTS FOR YOUR WINERY IN 2017 EQUIPPED FOR THE FUTURE ONLINEMARKETINGSYSTEM Wines Vines Analytics Visit winesandvines.com/OMS or call 866.453.9701 to set-up your free demo. Reach Thousands of Winery Decision Makers The Wines & Vines Online Marketing System is designed to help your business: • Increase sales • Generate winery leads • Manage clients and sales territories • Improve marketing effectiveness