Yield and yield components response of chickpea to time and different levels of humic acid foliar application

Yield and yield components response of chickpea to time and different levels of humic acid foliar application was studied in Bardaskan (northeast Iran) in 2011. experiment was carried out as factorial based on a complete randomized block design with three replications. Factors were foliar application time of humic acid at three levels (three leaf, flowering and poding stages), and different levels of humic acid concentrations (0, 2, 4 and 6 Lit.ha-1). Humic acid 8% was used with Humax trade name containing 80% humic acid, 5% potassium oxide and 15% fulvic acid. Yield and yield components response were different to foliar application time. Foliar application at flowering stage had the greatest effect on pod number per plant, seed number per plant, economic yield and biological yield, while foliar application at three leaf stage had the highest effect on plant height and lateral branches number in plant. Increasing humic acid level increased all parameters, except lateral branches number in plant. The highest pod number per plant, seed number per plant, economic yield and biological yield was obtained at 6 lit.ha-1 humic acid concentration. Overall, the result of this experiment showed that 6 lit.ha-1 humic acid application at poding stage can be recommended to achieve optimal economic performance.