Issue link: http://winesandvines.uberflip.com/i/90739
WineEast Grapegrowing Grape berry moth larvae and frass emerge from a maturing berry. GBM is in Texas, Michigan, New York and Pennsylvania among other states. Tracking Grape Berry Moth in the South Texas adapts prevention methods and pesticide treatments used in the north and east By Fritz Westover T he rapid expansion of the Texas wine and grape industry has brought with it an ever-increasing list of pest and disease pressures as vineyard production is pushed into newer areas of the state. One pest, the grape berry moth (Paralobesia viteana), has been identified in much of the state of Texas—including the central Texas Hill Country, the eastern, northeastern and Gulf Coast regions of the state—and has been particularly prob- lematic in vineyards planted near heavily wooded areas where dense stands of native grapevines are established. The damage caused by grape berry moth (GBM) is similar to that reported in other states with a long-standing history of this pest including Maryland, Michigan, New York, North Carolina, Pennsylvania and Virginia. 106 WINES & VINES NOVEMBER 2012 Wine East HIGHLIGHTS: • Grape berry moth, which consumes the flesh of young berries and al- lows them to rot, affects many of Texas' vineyard regions. • Protocols from cooler climates have helped develop programs in Texas. However, the temperature extremes require adaptation. • Accurate timing of treatments is critical, and proper timing may allow southern growers to use much less insecticide than elsewhere. The moths emerge from pupae in the spring, roughly about the time of bloom. They mate and female moths deposit eggs on young grape clusters. A new generation emerges from those eggs as tiny larvae, which pierce directly into developing ber- ries, often consuming the flesh of several berries before they mature and pupate, beginning a new generation of moths. Infested berries can decrease fruit quality by directly damaging berries within clusters and may cause additional damage if spoiled berries become source points for late- season rot complexes during wet seasons. As with other states, there are several gen- erations of the GBM within a single growing season in Texas and, with the help of the Texas A&M AgriLife Extension service, grow- ers are learning how to monitor and control this pest in a southern climate. Grape berry moth in a hot climate Most of the methods to help growers control GBM have been developed in