Influence of humic substance on vegetative growth, flowering and leaf mineral elements of Pelargonium x hortorum

Humic acid (HA) as a major portion of humic substances and organic mat- ter play an important role in soil fertility and environmental sustainability. Previous studies reported an enormous range of responses after HA appli- cation on plants. To investigate the influence of HA on pelargonium plants cv. ‘Hortorum’ this study was conducted as a randomized complete block design under greenhouse condition. Treatments included HA at ۰, ۲۵۰ and ۵۰۰ mg L ۱ concentrations that were added into the soil via irrigation. Application of HA at both ۲۵۰ and ۵۰۰ mg/L promoted plant growth char- acteristics; however, application of ۲۵۰ mg L ۱ of HA showed better improvement in terms of numbers of leaves, numbers of flowering shoots, and numbers of flowers per plant. Moreover, the length and diameter of the flowering shoot, inflorescence diameter, fresh weight of the aerial parts per plant, and leaf nitrogen (N) were improved only by ۲۵۰ mg L ۱ of HA application

کلیدواژه ها:

geranium ، humic acid ، vegetative growth ، flowering and leaf mineral elements