title: Isolation and characterization of ACC deaminase-producing fluorescent pseudomonads, to alleviate salinity stress on canola (Brassica napus L.) growth.
abstract: Salinity stress is of great importance in arid and semi-arid areas of the world due to its impact in reducing crop yield. Under salinity stress, the amount of 1-aminocyclopropane-1-carboxylate (ACC), a precursor for ethylene production in plants, increases. Here, we conducted research under the hypothesis that isolated ACC deaminase-producing Pseudomonas fluorescens and Pseudomonas putida can alleviate the stressful effects of salinity on canola (Brassica napus L.) growth. The experiments were conducted in the Soil and Water Research Institute, Tehran, Iran. Seven experimental stages were conducted to isolate and characterize ACC deaminase-producing Pseudomonas fluorescens strains and to determine factors enhancing their growth and, consequently, their effects on the germination of canola seeds. Under salinity stress, in 14% of the isolates, ACC deaminase activity was observed, indicating that they were able to utilize ACC as the sole N-source. Bacterial strains differed in their ability to synthesize auxin and hydrogen cyanide compounds, as well as in their ACC deaminase activity. Under salinity stress, the rate of germinating seeds inoculated with the strains of ACC deaminase-producing Pseudomonas fluorescens and Pseudomonas putida, and seedling growth was significantly higher. These results indicate the significance of soil biological activities, including the activities of plant growth-promoting bacteria, in the alleviation of soil stresses such as salinity on plant growth.
authors.affiliation: Department of Soil Science, Khoy Azad University, Iran.
authors.forename: Farzad
authors.initials: F
authors.lastname: Jalili
authors.forename: Kazem
authors.initials: K
authors.lastname: Khavazi
authors.forename: Ebrahim
authors.initials: E
authors.lastname: Pazira
authors.forename: Alireza
authors.initials: A
authors.lastname: Nejati
authors.forename: Hadi Asadi
authors.initials: HA
authors.lastname: Rahmani
authors.forename: Hasan Rasuli
authors.initials: HR
authors.lastname: Sadaghiani
authors.forename: Mohammad
authors.initials: M
authors.lastname: Miransari
mesh_terms: D029688:Brassica napus / Q000254:growth & development* / Q000382:microbiology*; D019755:Carbon-Carbon Lyases / Q000096:biosynthesis*; D005453:Fluorescence; D018525:Germination; D006856:Hydrogen Cyanide / Q000378:metabolism; D007210:Indoleacetic Acids / Q000378:metabolism; D011551:Pseudomonas fluorescens / Q000201:enzymology* / Q000254:growth & development / Q000302:isolation & purification; D016958:Pseudomonas putida / Q000201:enzymology* / Q000254:growth & development / Q000302:isolation & purification; D054712:Salinity; D013312:Stress, Physiological
chemical_list: D007210:Indoleacetic Acids; D006856:Hydrogen Cyanide; C033634:1-aminocyclopropane-1-carboxylate deaminase; D019755:Carbon-Carbon Lyases