Document Type : Original Article
Two field experiments were conducted out at Itay EL-Baroud Agricultural Research Station to investigate the effect of different levels of humic acid and mineral fertilization alone or in combination on two sunflower cultivars, Sakha 53 and G102 during two summer seasons 2016 and 2017. The treatments were, i.e. T1 (100% mineral fertilizers + zero humic acid), T2 (75% mineral fertilizers + 2 litters of humic acid/feddan), T3 (50% mineral fertilizers + 2 litter of humic acid/feddan), T4 (50% mineral fertilizers + 1 litter of humic acid/feddan) and T5 (0% mineral fertilizers + 2 litter of humic acid/feddan), foliar application of humic was done on 25, 35 and 45 day after sowing (DAS). The experiments were designed in RCBD using split plot with three replications. The results indicated that highly significant difference were found between sunflower cultivars, also found between fertilization treatments during the two seasons, Sakha 53 recorded the best values for plant height, head diameter , seed yield/plant and seed yield/fad, while Giza 102 achieved desirable values for days to flowering and oil %. The treatments T1 and T2 exhibited the best results for most studied characters such as plant height, head diameter (cm), stem diameter (cm), no. of seeds/plant, 1000-seeds weight/plant and seed yield/fad with exception of oil % and physiological maturity date. Best value of benefit cost ratio was obtained by T1 and T2 among treatments and Sakha 53 compared to Giza 102.