CALCIUM SPRAYS TO CONTROL PHYSIOLOGICAL DISORDERS OF ‘D’ANJOU’ PEARS

Each year, a serious loss can occur to the ‘d’Anjou’ pear, Pyrus communis L., industry because of physiological disorders.
Preliminary information suggested that pears with the disorders, alfalfa greening and cork spot were lower in levels of calcium than normal fruit.
Calcium sprays may be one approach for the control of certain disorders of ‘d’Anjou’ pears.
In one orchard with a history of alfalfa greening and cork spot, three (1979) and four (1980) sprays of calcium chloride at the rate of 680 g and 1360 g in 400 liters of water with and without a non-ionic spreader-activator reduced the incidence of alfalfa greening and cork spot.
The 1360 g rate of calcium chloride spray without the spreader-activator resulted in the highest level of calcium in the peel and flesh of the fruit.
However, considerable injury occurred on the surface of the pear fruit from spray applications of the high rate of calcium chloride.
Further trials are needed to determine the optimum rate and timing for calcium sprays for consistent control of pear disorders with minimum spray injury to fruit and leaves.

III International Symposium on Pear Growing

J.T. Raese, E.A. Stahly

https://doi.org/10.17660/ActaHortic.1982.124.16