click image to zoomVicky BoydReTain from Valent U.S.A. can be used to extend the pollination window of cherries.The California Department of Pesticide Regulation has registered two products from Valent U.S.A. Corp., for crop load management in fruit.
ReTain Plant Growth Regulator has been approved to manage cherry fruit set, according to a news release.
It works by delaying ethylene production in cherry flowers, extending pollen viability by 1-3 days, depending on the temperature, according to the release. The result is a longer pollination window and better fruit set.
The PGR is most effective on difficult-to-set varieties, such as Brooks, Corals and Chelans. In addition, it helps even good setting varieties, such as Brings, under poor pollination conditions.
Third-party trials have shown an increased set of 37 percent to 259 percent, according to the release.
ReTain already was registered for use on apples, pears, stone fruit and walnuts in California.
PoMaxa Plant Growth Regulator has been registered for use on apples and pears.
It is an auxin-based product that enhances the thinning effects of MaxCel Plant Growth Regulation. In addition, it can be used with ReTain to maintain fruit firmness and prevent fruit drop in apples and pears.