Effect of Humic Acid on Plant Growth, Nutrients Uptake and Postharvest Life of Gerbera
Nikbakht, A., M. Kafi, M. Babalar and Y.P. Xia. 2008. Effect of Humic Acid on Plant Growth, Nutrients Uptake and Postharvest Life of Gerbera. Journal of Plant Nutrition. 31: 2155-2167
Humic acid (HA) might benefit plant growth by improving nutrients uptake and hormonal effects. We examined the effect of HA on growth, macro – and micro-nutrient contents and postharvest life of gerbera (Gerbera jamesonii L.) cv. Malibu. Different levels of humic acid; (0, 100, 500 and 1000 mg/L) were applied to nutrient solution. Root growth increased at 1000 mg/L HA incorporated into the solution. Macro- and micro – nutrient contents of leaves and scapes including nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe) and zinc (Zn) significantly enhanced by HA. However, high levels of HA decreased some nutrients content. 500 mg/L HA increased the number of harvested flowers per plant (52%). Higher HA levels extended the vase life of harvested flowers by 2 – 3.66 days and could prevent and delay bent neck incidence. These postharvest responses were most probably due to Ca accumulation in scapes and hormone-like activity of HA.