Effects of potassium and humic acid on emergence, growth and nutrient contents of okra (Abelmoschus esculentus L.) seedling under saline soil conditions.

Abstract

The effects of potassium and humic acid (HA) on emergence, growth and nutrient contents of okra (Abelmoschus esculentus L cv. Sultani) seedlings in saline soil conditions were evaluated. Different levels of humic acid (0, 500, 1000 and 1500 mg kg-1) and potassium (0, 75, 150 and 300 mg kg-1) were applied on growing media treated with 50 mg NaCl kg-1 before seed sowing. The experiment was designed as randomized completely factorial block and each parcel had ten pots without drainage. Two okra seeds were sown in each pot having 300 cc volumes of growth media. The seedlings were thinned to one after emergence. The seedlings were irrigated with distilled water. Seed emergence, root and shoot size, leaf number, shoot and root dry weights of the plant seedlings were determined. Macro and micro nutrient (N, P, K, Ca, Mg, S, Cu, Fe, Mn and Zn) contents of seedlings were also determined. All data were subjected to a one-way analysis of variance and separated by Duncan’s multiple range test which was performed using the Costat statistical software. There were statistical differences in terms of effects of potassium and HA on the okra seedling performances. The effects of K, Ca, Na, Cu, Fe, Mn, Zn and HA applications on plant mineral (N, P, K, Ca, Cu, Fe, and Mn) contents were significant at p < 0.005. Key words: Okra (Abelmoschus esculentus L.), potassium, humic acid, nutrient content, seedling growth.