CALCIUM DEFICIENCY OF ARTICHOKE BUDS IN RELATION TO SALINITY

Globe artichokes (Cynara scolymus L.) were grown for 2 years in artificially salinized field plots in the irrigated desert area near Brawley, Calif. Saline treatments were imposed by irrigation with waters that contained equal weights of NaCl and CaCl2. Increased incidence and severity of Ca deficiency in the inner bracts of artichoke buds were directly related to increased levels of salinity. The Ca-deficient bracts were subject to infection by species of Botrytis and Erwinia. The number of marketable artichokes was reduced 20% or more when irrigation water salinity exceeded 2.0 dS.m-1, and up to 50% at 10 dS.m-1. Calcium deficiency in the artichoke bud is believed to be the result of disparate Ca distribution among the tissues, which is caused by high transpiration rates in the desert environment and the reduction in root pressure by soil salinity. Elemental analysis of leaf tissues can not be used to predict Ca deficiency within the artichoke buds.