Response of cornflower plants to the acidity of the agricultural medium and fertilization with Azolla

Abstract

      The purpose of this study was to evaluate the role of different levels of medium acidity and the addition of Azolla fertilizer on some vegetative, flowering, and root indicators of the Centaurea cyanus L. plant. This study was conducted in the fall season of 2022/2023. The experiment was designed in a randomized complete block design (R.C.B.D.) as a factorial experiment with three replicates and two overlapping factors: the first three levels of pH of the medium, which are 6-6.5, 6.5-7 and 7-7.5 (symbolized as H1, H2 and H3), and the second is four ratios. of Azolla fertilizer, which are 0, 10, 15 and 20% (symbol A0, A1, A2 and A3). The results were compared according to the least significant difference (LSD) test at the probability level of 0.05. The results showed that the acidity of the medium significantly affected the studied traits, with a level of 7-7.5 recording the highest values for plant height, number of main branches, number of side branches, number of leaves, leaf area, root length, and number of flowers. While the Azolla addition treatment caused significant differences in the studied traits, as the 20% treatment recorded the highest values in most of the studied traits. The interaction between the two factors was significant, and the highest values were in plant height, number of main and lateral branches, number of leaves, and leaf area, in treatment H3A3.