EFFECT OF WATER SALINITY GIBBERELLIC ACID ON LEAF AREA AND COMPENET WHEAT YIELD

Abstract

The experiment were carried out at Diyala Directorate of Agriculture Research Station field crops during the winter of 2013 and 2014. The objective of the experiment was to study the effect of gibberellic acid foliar on wheat crop tolerance to levels of water salinity in different stages of growth, according to the scale (Zadoks and others, 1974) for small grains and this impact on some characteristics, yield and yield components of wheat (IPA 99 var.). Randomized complete block design with three replications by split-plot arrangement was used for the experiments. The main plots included four levels of water salinity treatments (water concentration of salt 7, 14, 21 dS m-1, river water) in both seasons. While sub-plots included Gibberellic acid foliar treatments in different concentrations according to the stages of crop growth (150 300 450) mg l-1. The results of the experiment showed negatively effect of water salinity S3 level (21 dS m-1) on the mean of all characteristics, including the grain yield, which was significantly lower rate 79.00 and 79.60% for two seasons respectively. G3 treatment (sprayed acid Gibberellic concentration of 450 mg l-1) caused increase area of flag leaf, number of spikes, the number of grains in spike and yield grain in the two seasons respectively. The combination S0G3 (river water gibberellic acid foliar concentration of 450 mg l-1) also recorded the highest average area of flag leaf, number of grains per-spike, 1000-grain weight and yield grain in the two seasons. The combination S1G3 (water concentration of salt 7 dS m-1 gibberellic acid foliar concentration of 450 mg l-1) excelled in number of spikes in the first season. Combination S3G0 (water concentration of salt 21 dS m-1 without gibberellic acid recorded the lowest average area of flag leaf, number of spikes, number of grains per-spike and grain yield in the two seasons respectively.