Effect of foliar application of Humic acid and Nano fertilizer (Farmks®) on growth index, yield, yield components essential oil content and yield of Black cumin (Nigella sativa L.)

Today, in a sustainable agriculture system, application of the fertilizers which are nature friendly and suitable for plants is essential. This becomes more important when dealing with medicinal plants. Therefore, a factorial experiment in a randomized complete block design with three replications was set up in the 2011-2013 on Nigella sativa. Treatments were Nano fertilizer (Farmks®) (at 2 levels 0, 1 ml/l) and humic acid (at 4 levels zero, 1, 3, 6 ml/l) which were applied at three time of plant growth. Results showed that different levels of humic acid imposed a significant effect on plant height, leaf area index, dry weight, number of branches, and number of follicle per plant, number of seeds per follicle, seed weight, seed yield, biological yield harvest index, essential oil content and yield. The highest yield was in levels of 3, 6 ml/l of humic acid treatments, respectively. Nano fertilizer (Farmks®) application significantly increased the yield and yield components of Nigella sativa. Combined treatment at various levels had significant effect on dry weight, seed weight, seed yield, biological yield and harvest index respectively but had no significant effect on other traits. According to these results, we can conclude that the humic acid and Nano fertilizer (Farmks®) application could increase yield, yield components, essential oil contentand and yield.also, combination treatment (humic acid and Nano fertilizer) ware more effective in increase of essential oil content and yield. Therefore, the application of this kind of fertilizers can be advisable in Nigella sativa.