Performance of different wheat genotypes inoculated with the plant growth promoting bacterium Herbaspirillum seropedicae

Abstract

Several diazotrophic bacteria can promote plant growth and increase crop productivity. However, such effects are variable probably due to interaction between the plant genotype and the bacterial strain, soil properties and climatic factors. The aim of this study was to evaluate the performance of wheat genotypes inoculated with Herbaspirillum seropedicae SmR1, an endophytic diazotrophic bacterium. In vitro plantlets of five wheat genotypes were inoculated with H. seropedicae for 7 days. The fresh weight of roots, fresh and dry weight of shoots, total nitrogen, root morphology and bacterial counts were determined. For greenhouse experiments, seeds were inoculated or not with H. seropedicae (106 cells/seed) cultivated in the absence or presence of urea. At harvest dry weight of shoots, grain index and grain yield were evaluated. In vitro results showed the presence of epiphytic bacteria on all genotypes and the presence of endophytic bacteria in CD 108 and CD 120. An increase in root hairs in genotypes CD 119 and 120 was observed. Two contrasting genotypes (CD 104 and CD 120) were evaluated under greenhouse conditions. The results showed that cultivar CD 120 inoculated with H. seropedicae had a higher productivity when the plants were not supplemented with urea. Data emphases the potential of H. seropedicae as a biofertilizer, reducing costs and improving agricultural sustainability.