Abstract:
A Pseudomonas aeruginosa strain, RRLJ 04, and a Bacillus
cereus strain, BS 03, were tested both individually and in combination
with a Rhizobium strain, RH 2, for their ability to
enhance plant growth and nodulation in pigeon pea (Cajanus
cajan L.) under gnotobiotic, greenhouse and field conditions.
Both of the rhizobacterial strains exhibited a positive effect
on growth in terms of shoot height, root length, fresh and dry
weight, nodulation and yield over the non-treated control.
Co-inoculation of seeds with these strains and Rhizobium
RH 2 also reduced the number of wilted plants, when grown
in soil infested with Fusarium udum. Gnotobiotic studies confirmed
that the suppression of wilt disease was due to the
presence of the respective PGPR strains. Seed bacterization
with drug-marked mutants of RRLJ 04 and BS 03 confirmed
their ability to colonize and multiply along the roots. The
results suggest that co-inoculation of these strains with Rhizobium
strain RH 2 can be further exploited for enhanced
growth, nodulation and yield in addition to control of fusarial
wilt in pigeon pea.
