The role of fractionation of humic acids and spraying with azolla extract on vegetative growth indicators growth of sunflower crop (Helianthus annuus L.)‎

Abstract EN

A field experiment was carried out during the spring season of 2022 at a farm in the Al-Khader district 30 km south of Samawah.

The experiment was conducted to study the role of fractionation (30 kg H-1) of humic acids for three batches (First batch, Second batch and Third batch) and spraying with Azolla extract using four concentrations ( 0%, 20%, 40%, 60%), on the vegetative growth indicators of sunflower.

The treatments were arranged as a split-plot design with two plots, the fractionation (30 kg H-1) (Al-Mughayer, 2019) of humic acids in the main plot and Azolla spray concentrations in the second plot, using three replications .The results showed a superiority in the second batch for the percentage of nitrogen in the leaves with an average of (1.27%) and did not show significant differences in the plant height, number of leaves per plant, leaf area and stem diameter.

Foliage and stem diameter were (34.06 leaves -1, 9514 cm2 one plant and 28.14 mm) for the characteristics, respectively, while the spraying concentration of 60% was superior in the percentage of nitrogen in the leaves with an average of (1.25%).

The interaction between the study factors was high significantly, as was (40% Azolla extract at the second batch) the highest average of nitrogen content in the leaves, which was up to (1.30%).