Biocontrol potential of endophytic fluorescent Pseudomonas isolated from Salvadora species
S. EHTESHAMUL-HAQUE (1), F. Korejo (1), V. Sultana (2), S. A. Ali (3), J. Ara (4). (1) Department of Botany, University of Karachi, Karachi, Pakistan; (2) Department of Biochemistry, University of Karachi, Karachi, Pakistan; (3) HEJ Research Institute of Chemistry, University of Karachi, Karachi, Pakistan; (4) Department of Food Science
The <i>Salvadora</i> species have a number of proven medicinal applications and almost all parts of this plant have pharmacological importance. Plants are able to tolerate dry environment and high soil salinity. In the present study 62 isolates of endophytic fluorescent <i>Pseudomonas</i> were isolated from roots, shoots and leaves of two species of <i>Salvadora</i> i.e. <i>S. persica</i> and <i>S. oleoides</i>. Most of these isolates were identified as <i>P. aeruginosa</i>. <i>In vitro</i> test several isolates showed strong antifungal activity against root rotting fungi <i>Macrophomina phaseolina</i>, <i>Rhizoctonia solani</i>, <i>Fusarium solani</i> and <i>F. oxysporum</i>. Cell free culture filtrates of these isolates also showed significant nematicidal activity by killing the 2nd stage juveniles of root knot nematode (<i>Meloidogyne javanica</i>), at varying degrees. Application of potential isolates of <i>P. aeruginosa</i> as soil drench significantly prevented the attack of root rotting fungi and root knot nematode on mungbean, sunflower and cotton plants both in screen house and field experiments by reducing the fungal root infection and nematode’s penetration in roots. Endophytic fluorescent <i>Pseudomonas</i> also caused a positive impact on plant growth by producing taller plants and healthy roots with increased in fresh shoot weight. Endophytic fluorescent <i>Pseudomonas</i> offer a non-chemical means of plant diseases control.
View Presentation |
