Effect of Calcium Salts Trunk Injection on Intensity of Mozafati Date Palm Bunch Wilting and Drying Disorder

Date palm bunch wilting and drying disorder has been the most important problem of Iran palm producers in recent years. Reduction of relative humidity and increased air temperatures are known as the major causes of this disorder. Calcium decreases plants injuries due to environmental stress, though its movent in plants is slow. Increase in cell sap concentration with calcium injection can increase cell resistance when temperature increases suddenly, thereby preventing fruit injury. In order to investigate the effect of calcium salts trunk injection on this disorder, an experiment was conducted since 2003, using four replicatios of a randomized complete block design with 7 treatments: Check, injection of saturated solution of calcium sulfate, %1 solution of calcium nitrate and chloride in two times (second half of Feb and Apr). Every plot contained one tree in two garden that had been infected with this disorder in recent years. A hydraulic pump was used to inject the solution into tree trunks. Results showed three different groups of disorder injury. The first group consisted of the check (76.3% injury), calcium chloride, and sulfate treatments, indicating that these two salts had no significant effect on reduction of disorder injury. The second group was injection of calcium nitrate in the second half of Feb that had significantly decreased disorder injury in contrast to the first group (48.5 %). The least disorder injury was observed in the two-stage injection of calcium nitrate (38.5%).Correlation of mean leaf calcium concentration and disorder injury was significant in one of the experimental sites (R=-0.88**).Calcium concentration of bunch and leaf increased significantly with high pressure injection method, indicating that, in similar conditions, this method can be used to provide nutrients to the palm trees.