Evaluation of Yield and Yield Components of Maize by Foliar Application of Salicylic Acid

To study the effect of salicylic acid concentrations and foliar application times on yield and yield components of maize in the northern Khuzestan, a field experiment in 2014-2015, as factorial in the form of randomized complete block design with three replications was conducted. Experimental factors were salicylic acid concentration in five levels, 0, 0.25, 0.5, 0.75 1 Mm and foliar application times with three levels: once at 6-8 leaf stage, twice at 6-8 leaf stage and ten days after that, thrice at 6-8 leaf stage and twenty days after that. Results showed that the leaf area index, grain yield and yield components, like grain thousand weight, number of kernel rows per ear and number of kernels per row, were affected significantly by different salicylic acid concentrations and foliar application times, but the effect of salicylic acid concentration ×foliar application time interactions were not significant. Biologic yield was affected by different concentration of salicylic acid. The highest biologic yield of 18150 kg/ha related to 0.75 Mm salicylic acid concentration and lowest to control (no foliar application) with 15140 kg.ha-1, but the effect of foliar application times and their interactions were not significant. Foliar application of salicylic acid increased grain yield. The highest grain yield of 8998 kg.ha-1 related to 1 Mm concentration treatment and lowest (6897 kg.ha-1) to control (no foliar application). Highest grain yield (8592 kg.ha-1) belonged to two time foliar applications, at 6-8 leaf stage and ten days after that. The conclusion is that the application of salicylic acid could be beneficial in increasing grain yield of maize.