Résumé:
Plant Growth-Promoting Rhizobacteria (PGPR) can form an associative
symbiosis with plants, which results in stimulation of plant growth. PGPR harbour
different phytobeneficial mechanisms (non-symbiotic nitrogen fixation, phytohormone
synthesis, etc.). The objective of the present study is the improvement of some PGP
activities in the two strains of Stenotrophomonas maltophiliaa NHA68 and NHA78 by
physical mutagenesis with UV rays at different exposure times (0, 5, 10, 15, 20, 25 and
30 mins). After mutation, a high improvement in AIA production was observed in
mutant strains NHA68-m18 and NHA78-m5, and a strong improvement in phosphate
solubilization in mutant strains NHA68-m18, NHA68-m20, NHA68 -m17, NHA78-
m14, NHA78-m4, NHA78-m12 and NHA78-m19