Submitted to: Annual Cumberland Shenandoah Fruit Workers Conference
Publication Type: Proceedings
Publication Acceptance Date: 1/25/2006
Publication Date: 2/20/2006
Citation: Miller, S.S. 2006. Three successive years of apogee on young 'nittany' apple trees on m.9 rootstock. Vol. 81., pg 194-198. 2006 . Annual Cumberland Shenandoah Fruit Workers Conference. Interpretive Summary:
Technical Abstract: Two sprays of Apogee plant growth regulator were applied annually to young ‘Nittany’/M.9 apple trees over a 3-year period. The first spray was applied near petal fall at 125 ppm and a second spray applied 14 days later at 63 ppm. These low-dose Apogee sprays consistently reduced terminal shoot growth, which led to reduced tree height and canopy spread compared to the untreated control trees. Apogee had no effect on return bloom in two seasons following spray treatment and little or no effect on fruit quality. Two Apogee sprays significantly reduced the number of fire blight strikes in a year with heavy fire blight infection pressure. Except for the initial treatment year, Apogee sprays had no effect on annual yield and no effect on cumulative yield. Apogee may reduce fruit size independent of fruit set. The potential reduction in fruit size as it relates to fruit set on Apogee treated trees warrants additional study.