The trial has been initiated in 2017 to test the effect of a new compound, Splendor, registered in CA for the promotion of berry fruit growth and prevention of berry splitting after rain. Splendor’s active ingredient, forchlorfenuron or CPPU is a synthetic cytokinin-like plant regulator that at low concentration promotes berry development and increase fruit size. In the trial, this product has been applied alone or in the combination with ReTain, a plant growth regulator that has been shown to extend flower viability in cherries by reducing ethylene production in flowers and delaying flower and stigmatic senescence. Due to this effect, flowers that last longer have a higher likelihood to be successfully pollinated, and increased pollination results in a higher yield.
To test the effect of the products on yield and fruit size, ReTain spray was applied at bloom, with rate of 50g/acre, while Splendor with the rate of 6g a.i./acre was sprayed at fruit set.
Combination of ReTain and Splendor increased yield per tree which reflected on smaller berry size. Threes on which Splendor was applied alone have higher yield than untreated control (UTC) and bigger fruit size compared to threes which received combination of ReTain and Splendor.
A potential impact of Splendor on resistance to fruit splitting was test by spraying this product at color break. Compared to UTC, treated cherries showed higher percentage of fruit without cracks.