1100-1106The study was undertaken to understand effects
and survival of S. enterica subspecies enterica serovar Typhimurium
(S. Typhimurium), a zoonotic serovar,
on maize seed germination and plant growth. All the four strains of S. enteric
subspecies enterica serovar Typhimurium significantly reduced germination
of maize seeds in sprouting plates as well as in soil. About ≥2.7×103
Salmonella cfu ml-1 of soaking water, while ≥2.7×107
Salmonella cfu g-1 soil were required to significantly inhibit
germination of maize. Similar inhibition of germination could be observed using
≥16 mg of bacteria free Salmonella cell lysate (CL) protein per g of soil
or ≥0.5 mg of CL protein per ml of soaking water in sprouting plates.
At the constant dose of 3.6×107
to 3.8×107 Salmonella cfu or 5 mg cell lysate protein ml-1
of soaking water, four strains of Salmonella significantly reduced germination,
however difference between strains was insignificant. After germination too, maize
growth was affected both by Salmonella organism and CL with little strain-to-strain
variation. All Salmonella persisted in growing plants from 15 to 35 days
of plant age and up to 190 days in soil. Maize plants once grown for a week in sterile
soil were resistant to invasion of S. enterica subspecies enterica
serovar Typhimurium in their leaves even in doses as high as 7.6×109
cfu g-1 of soil. Salmonella persisted better and longer in plants
grown from contaminated seed sown in loam soil, but rarely in plants grew in sandy
soil. All maize plants had Salmonella in their stumps even after 35 days
of sowing irrespective of kind of soil, primary source of infection (soil or
seed) and type of S. enterica subspecies enterica
serovar Typhimurium strain. The study revealed
that Salmonella is not only zoonotic but a phytopathogen also