Effect of inoculation with putative plant growth-promoting rhizobacteria isolated from Pinus spp. on Pinus pinea growth, mycorrhization and rhizosphere microbial communities.
OBJECTIVE
In this study, 10 putative plant growth-promoting rhizobacteria (PGPR) were assayed for their ability to improve Pinus pinea growth and mycorrhization.


RESULTS
After an inoculation assay, except for two, all strains stimulated plant growth. All bacteria altered rhizosphere microbial communities as revealed by phospholipid fatty acid analysis; associating plant growth promotion with a decrease in biological diversity. Three strains were tested for their ability to enhance pine mycorrhization with wild fungi species. Only strain BB1 increased the total number of mycorrhizal root tips. Mycorrhizas present in the roots of each treatment were identified by ribosomal RNA sequencing and denaturing gradient gel electrophoresis analysis, detecting specificity between mycorrhizal species colonizing the roots and the inoculated PGPR.


CONCLUSIONS
In conclusion, BB1 appears to be a good candidate to be developed into a biofertilizer directed to enhance pine growth and mycorrhization, which should result in a better establishment rate for plants used in reforestation.


CONCLUSIONS
This study shows the potential of PGPR to improve fitness of forest tree specie. Moreover, the specificity between the bacteria inoculated and the mycorrhiza that the plant selects involve a potential biotechnological use in production of value-added fungi.
Barriuso
J
J
Universidad San Pablo CEU, Facultad de Farmacia, Boadilla del Monte, Madrid, Spain. jbarriuso@ceu.es
Ramos Solano
B
B
Santamaría
C
C
Daza
A
A
Gutiérrez Mañero
F J
FJ
D005227:Fatty Acids / Q000378:metabolism; D038821:Mycorrhizae / Q000254:growth & development*; D010743:Phospholipids / Q000378:metabolism; D028223:Pinus / Q000254:growth & development / Q000382:microbiology*; D018517:Plant Roots / Q000254:growth & development* / Q000382:microbiology; D012231:Rhizobium / Q000254:growth & development* / Q000378:metabolism; D036226:Seedlings / Q000254:growth & development; D012987:Soil / Q000032:analysis
D005227:Fatty Acids; D010743:Phospholipids; D012987:Soil