Elhafid Nabti
University of Bejaia, Algeria
Title: Implication of Pseudomonas spp. in stimulation of bean germination and common bean blight biocontrol in western Algeria
Biography
Biography: Elhafid Nabti
Abstract
Problematic: the work focused on the determination of functional diversity of soil bacteria; study their effects on seed germination and biological control of common bean (Phaseollus vulgaris L).
The identification of the isolates based on physiological and biochemical characters and BOX-PCR followed by qualitative and/or quantitative analysis of their secondary metabolites. 50 soil bacteria isolates were affected to the two groups of fluorescent Pseudomonads (76 %) and non-fluorescent Pseudomonads (24 %). The UPGMA method showed five phenons of carabon sources assimilation; at the time that BOX-PCR profiling resulted in 5 clusters characterized by 29 different applotypes. (66 %) isolates induced phosphate solubilization; (24 %) were HCN producers, (21 %) showed IAA production and all isolates had produced siderophores. In vitro antibacterial activity against Xapf results in screening of two isolates P25 P. aeruginosa characterized by an inhibition zone of (26.67±2.31 mm) and P7 P. cepatia (24±0 mm). In vivo biological control of Xapf revealed that the two isolates reduced significantly bean common blight intensity. Isolate P7 was the highest effective. Coinoculation of the two isolates was not very effective on controlling Xapf. Study of the effects of the two isolates on bean seed germination, revealed that isolate P7 was the highest effective on seed germination and root growth properties, then isolate P25 or the coinoculation of the two bacteria. Conclusion: Bacterial isolates could play a crucial role in the biocontrol of beans and the enhancement of seed germination, thus increase crop yield.