Investigating the effect of gibberellic acid and kinetin hormones on proline, protein and carbohydrates of leaf soluble in maize hybrids under drought stress

Abstract. Hormones play a critical role in regulating the plant growth and responding to drought stress. In order to study the relationship between water scarcity and gibberellic acid and kinetin hormones in three experimental maize hybrids for two years, we carried out Factorial Split Plot Design and the experiment was based the randomized complete blocks design which was carried out with 3 replications. Results showed that the drought stress is an effective factor on hormone balance changes of maize. In comparison to the control (group), kinetin and gibberellin showed the highest mean amount of proline in the leaf. Also, compared to the control group, the amounts of carbohydrates increased under the hormone spraying. However, in comparison to the usage of the grain, the grain yield trait as the major economic trait showeda positive effect و so it is recommended to apply these hormones to the maize.