Response of Some Growth Traits of Safflower(Carthamus tinctorius L.) to Spray with Humic Acid Under Levels of Phosphorus Fertilizer

Abstract

The research was carried out in Agriculture College farm / Basra University – Karmat Ali location, the winter season 2020- 2021, to study the response of Safflower variety Gilla to spray with four concentrations of humic acid (0,6,12,18g L-1) under four levels of Phosphorus fertilizer(0,60,120 kg P h-1). The experiment was carried out in a factorial arrangement with three replications using a randomized complete block design. The results showed that 120 kg P h-1 gave of the highest days until 50% flowering, plant height, the total number of main branches and leaves and a diameter of the stem (106.75 days ago, 183.01cm,12.44 branches plant-1, 588.71 leaves plant-1,1.466cm respectively). The maximum number of days to 50% flowering plant height, the number of main branches were superior with a humic acid concentration of 12 g L-1., (109.56 day,180.34cm and 12.70 branches plant-1respectively), while concentration 18 g L-1 gave the highest number of leaves. The interaction of 120 kg P h-1 with 12 g L 1- of humic acid gave the highest number of days from planting to 50% flowering, plant height, the number of main branches.