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Abstract
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Abstract
Salinity disrupts the germination and growth of seedlings in plants and reduces the population of soil microorganisms, especially
bacteria. Scientists have found that each normal soil contains 600 million bacteria, consisting of 20,000 species, and
their number is reduced to 1 million bacteria, consisting of 5000 to 8000 species, under salt stress. Many engineering methods
are not practical. One of the biological methods is seed inoculation with plant growth-promoting rhizobacteria (PGPR).
PGPR improves the morphological traits of plants, which include 1 — extracellular plant growth-promoting rhizobacteria)
ePGPR( and 2 — intracellular plant growth-promoting rhizobacteria)iPGPR(. ePGPRs are present in the rhizosphere, on the
rhizosphere, or in the spaces between the cells of the root cortex, while iPGPRs are present inside the specialized nodular
structures of the root cells. The aim of this experiment was to investigate the effect of several rhizobacterial isolates obtained
from the rhizoplane of saline soil in Momghan on seed germination and wheat seedling growth at different salinity concentrations.
The experiment was conducted using a randomized complete block design. The first factor had five levels: control,
3, 6, 12, and 18 ds/m, while the second factor, involved seed inoculation with 10 bacterial isolates. The experiments were
carried out in 3 replications. Isolates R2
and R7
promoted the growth index. At salinity levels of 3 and 6 ds/m, a significant
difference was observed at the 5% level. At concentrations of 12 and 18 ds/m, morphological traits improved growth. The
isolates were identified using biochemical and molecular 16s rRNA tests. Isolate R2
was placed in the genus Pseudomonas
sp. and isolate R7
in the species Serratia odorifera.
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