Abier Raouf Mahmoud Al-Qaissi *⁽¹⁾, Abdullah Abdul-Karim Hassan ⁽²⁾, and Waleed Mohammad Saleh ⁽¹⁾

(1). Agricultural Research Office –   Ministry of Science and Technology, Salah Aldin, Iraq

(2). Tikrit University, College of Agriculture, Salah Aldin, Iraq.

(*Corresponding author: Dr.AbierMahmoud Al-Qaissi. E-MailAbiers2014@gmail.com).

Received:12/06/2023                 Accepted: 2/08/2023

Abstract: 

Thirteen bacterial isolates were isolated from the rhizosphere of wheat plants (cultivar Sham 6), from different locations in Salah El-Din Governorate in Iraq for the agricultural season 2020-2021. These bacterial isolates were screened depending on the ability inhabit the pathogenic fungus Fusarium solani growth on the nutrient agar medium. The isolates Ar-7, Ar-10 and Ar-3 were significantly superior by recording the highest inhabitation, which reached 9.85, 7.33 and 6.12 mm, respectively. These isolates were molecularly identified as Psudomonas fluorescences, Bacillus amyloliquefaciens and Bacillus subtilis according to the matching of the nucleotide sequences of the 16S rRNA gene of these isolates with the global strains recorded in the World Genetic Bank (NCBI), which matched by 99.03-98.65%. P. fluorescences significantly outperformed by recording the highest hydrogen cyanide production, as it recorded the highest absorbance of 0.894 nm, with the superiority of the treatment of a mixture of three bacterial filtrates of these isolates significantly under disease stress inducing systemic resistance of the plant by increasing the activity of peroxidase and polyphenol oxidase, which reached 1.436 and 1.046 units/ml, respectively. In addition to the superiority of the same treatment by recording the lowest infection severity amounting to 6.64%, In addition to its significant superiority over all other treatments in the wheat productivity, as it gave the highest grain weight and 1000 grain weight, reaching 20.41 g/plant and 32.82g/1000grains, compared to 7.57 g/plant and 13.7 g in the pathogenic fungus treatment.

Keywords: Rhizosphere, PGPR, wheat/ sham 6, root rot disease, Fusarium solani.

Full paper in Arabic: pdf