EFFECT OF FERTILIZERS, ROOTSTOCKS, AND SEASON ON FRUIT QUALITY, FRUIT DISORDERS, AND MINERAL COMPOSITION OF D'ANJOU PEARS
Bearing 'd'Anjou' pear trees (Pyrus communis L.) on 2 rootstocks were treated with 3 rates and 3 sources of nitrogen (N) fertilizers to study the influence of season and mineral composition of leaves and fruit on fruit quality and the incidence of fruit disorders.
The orchard was located near Wenatchee, Washington and had a history of poor fruit quality primarily due to fruit disorders such as Cork Spot and Freckle Pit.
During the 8-year study, shoot growth, leaf size and overall tree vigor increased with the high rates of urea and calcium nitrate fertilizers.
More recently, tree vigor and fruit size was increased even more with mono-ammonium phosphate fertilizer.
But the high rate of fertilizers had only a small effect on yield and fruit size.
Freckle Pit, Cork Spot and blemishes on fruit from Psylla pyricola increased in trees treated with high rates of N fertilizers.
Fruit firmness was inconsistent with treatments while soluble solids and titratable acids were slightly higher in fruit from trees treated with the lower rate than the higher rates of nitrogen fertilizer.
While nitrogen in fruit was highest for trees receiving the high rates of nitrogen fertilizer, fruit calcium showed no consistent pattern with fertilizer treatment.
However, fruit calcium in the peel was lowest in years with a high incidence of Cork Spot and high fruit calcium content occurred in years with a low Cork Spot incidence.
Seedling (Bartlett) root produced a more vigorous tree with a higher incidence of Cork Spot and Freckle Pit than trees growing on 'Old Home X Farmingdale' root.
Raese, J.T. and Staiff, D.C. (1989). EFFECT OF FERTILIZERS, ROOTSTOCKS, AND SEASON ON FRUIT QUALITY, FRUIT DISORDERS, AND MINERAL COMPOSITION OF D'ANJOU PEARS. Acta Hortic. 256, 183-188
DOI: 10.17660/ActaHortic.1989.256.26
https://doi.org/10.17660/ActaHortic.1989.256.26
DOI: 10.17660/ActaHortic.1989.256.26
https://doi.org/10.17660/ActaHortic.1989.256.26