The effect of AVG and Promalin on fruit set of apple trees under adverse pollination conditions
'Gala' and 'Fuji' and their strains are the main cultivars grown in southern Brazil, accounting for 60 and 30%, respectively. In 'Gala', blossoms are naturally abundant, and in some years fruit set can be reduced due to adverse conditions at pollination time through environmental effects or intrinsic factors within the trees. Therefore, different rates of aminoethoxyvinylglycine combined with Promalin were tested in order to improve fruit set of 'Royal Gala' in four different seasons. The trials were carried out in Fraiburgo, SC, Brazil. The treatments and rates were: non-treated trees (control), AVG 30 ppm, AVG 60 ppm and AVG 120 ppm and each rate of AVG combined with Promalin 0.5 mL L-1. Trees were treated between E2 and F phenological stage (pink and king bloom stage). In general, AVG or AVG+Promalin increased fruit set. The lowest fruit production tree-1 was observed in the control trees during the four-years, averaging 47.3 kg. There was an increase of 124.7% in productivity with AVG 30 ppm (106.3 kg tree-1) compared to the control. Fruit weight was not affected by the different treatments.
Petri, J.L., Couto, M., Francescatto, P. and Gabardo, G. (2017). The effect of AVG and Promalin on fruit set of apple trees under adverse pollination conditions. Acta Hortic. 1177, 235-240
Malus domestica, yield, yield efficiency, fruit seed number, fruit shape