Effects of application mode and different concentrations of humic acid on yield and content of nutrients uptake of Rosa chinensis var. minima  Baby Masquerade'

This research was conducted to study the effects of soil and foliar applications of humic acid on the growth and flowering characteristics and nutrient uptake of Rosa chinensis var. minima ‘Baby Masquerade’ as a factorial experiment based on completely randomized design with two factors: four concentrations of humic acid (0, 500, 1000 and 2000 mg.l-1) and two application methods (drench and spray) with three replications and two observations in the research greenhouse of Urmia University in 2014-2015. The results indicated a significant effect of humic acid on the growth traits (such as fresh and dry weight of leaf and stem diameter), flowering characteristics (such as the number and diameter of buds and flower diameter) and nutrient uptake of Rosa chinensis var. minima ‘Baby Masquerade’. The results showed that soil application of 2000 mg l-1 humic acid caused to high absorption of nitrogen (8.425 µg/per pot) and iron (8.12476 µg/per pot) in the plant, but the absorption of Zn was not affected by the concentrations of humic acid. High Cu absorption was observed in 1000 mg l-1humic acid (46.342 µg/ pots). The absorption of Mn and K was high in 1000 mg l-1 HA. As a result, application of humic acid in plants caused to enhance some essential elements absorption and plants growth.