Isolation and Identification of Pseudomonas Bacteria Promoting Plant Growth from Rhizosphere of Some Plants Growth in Gypsiferous Soils in Salah-Aldin Governorate

Abstract

Twenty samples of gypsiferous soil were collected from the rhizosphere soil of different plants (wheat Triticum aestivum , barley Hordeum vulgare , Zea mays L, alfalfa Medicago sativa , Mentha pulegium L) to isolate and diagnoses the Pseudomonas bacteria from these samples, the diagnostic process was conducted based on the culture, microscopic and biochemical characteristics, as well as the diagnosis was confirmed by using device Vitek 2 compact system, the results showed that the Pseudomonas putida species scored the highest percentage ratio of the frequency reached (55%), followed by the Pseudomonas fluorescens species as a percentage reached (30%), while the species Pseudomonas aeurginosa and Pseudomonas cepacia and Pseudomonas pseudomallei gave a percentage of the frequency reached (5%) for each one of these isolates. The results of the ability of these bacteria isolates on indole acetic acid (IAA) production and phosphate solubilizing and Siderophore production, showed that the isolate KH-K13 which belong to P. fluorescens gave the highest values in production of IAA reached 9.12 5 µg/ml and phosphate solubilizing reached 2mm and production of Siderophore average, followed by P. putida (KH-K12) which gave 7.62 µg/ml , 1.86 and average respectively, then 5 µg/ml, 1.68 and average respectively for P. cepacia (KH-K20) isolate , then 3.12 µg/ml , 1.40 and average respectively for P.pseudomallei (KH-K4) isolate, while the P. aeruginosa (KH-K10) isolate was not capable of phosphate solubilizing , but is capable of IAA production reached 3.65 µg/ml and it showed a high capable for the production of Siderophore .