Hadeel Chasib Abbas⁽¹⁾  and Abd al-Nabi Abd al-Amir Matroud^*(1)

(1). Plant Protection Department, College of Agriculture, Basrah University,Iraq.

(^* Corresponding author: Dr. Abdulnabi Abbdul Ameer Matrood. E-Mail: abdul_nabi.matrwod@uobasrah.edu.iq).

Received: 27/07/2022                    Accepted: 29/11/2022

Abstract: 

  This study showed the ability of two isolates of the pathogenic fungus A.alternata in the water agar medium. The isolate of fruits had the most effect on the severity of infection of tomato seeds in the dish, reaching 59% compared to isolate the leaves, which amounted to 47%. The results of the antagonism test for T.viride and T. .koningii in PDA culture medium had a high antagonistic ability against A.alternata by spot method, the inhibition zone reached (2.3, 1.8), respectively. The filtrates of biological resistance fungi showed inhibition of the pathogenic fungus A.alternata when used at concentrations of (10,20,30)% with PDA culture medium. When analyzing the infiltrates of T.viride and T.koningii using GC-MS technique, several chemical compounds that have a role in inhibiting pathogens were obtained, including n-Hexadecanoic acid and Octadecanoic acid. As for the total phenol content in the leaves of the tomato plant, T.konhngii treatment gave the highest content of phenol, as it reached 0.56 mg. Also, chlorophyll was increased in tomato leaves, so the T.v + T.k treatment gave the highest percentage of chlorophyll, which amounted to 47.55 mg, compared to the fungus A.alternata treatment, which amounted to 36.13 mg .The biological resistance fungi also reduced the severity of infection with the pathogenic fungus A.alternata, which amounted to 19.66% in the treatment of T.konhngii, compared to the treatment of the pathogenic fungus, which amounted to 50.36%.

  Key words: Tomato, Trichoderma koningii, Trichoderma viride, Alternaria alternata.

Full paper in Arabic: pdf