The underlying interactions in rhizosphere micro-ecosystem accelerate
the premature senescence of OsVHA-A1 mutant rice
Abstract
Abstract Root-pathogen interactions are an important factor
accelerating premature senescence of rice, however, few study have
addressed the underlying interactions in rhizosphere micro-ecosystem. In
this study, the OsVHA-A1 mutant rice line displayed an early
senescent phenotype associated with a special rhizosphere microbiome in
contrast to the wild type. Moreover, the pathogen Gibberella
intermedia had been shown to sharply increase when premature senescence
occured in OsVHA-A1 mutant. Using GC-MS analysis, we found the
composition of root exudates from the senescent rice were different from
the WT. In addition, transcriptome data revealed that G.
intermedia preferred using sugars from root exudates that had been
generated by fructose and mannose metabolism in the mutant. Furthermore,
the OsVHA-A1 mutant would display cell death in both
physiological and molecular levels when suffering from pathogenic
infection by G. intermedia. However, such fungi showed a weaker
virulence for infecting the WT. Finally, Bacillus and
Burkholderia could be used as antagonistic bacteria that could
effectively alleviate the early senescent phenotype of OsVHA-A1
mutant rice thereby improved its grain yield. Keywords:
OsVHA-A1, premature senescence, microbiome, G. intermedia,
GC-MS, transcriptome, sugars, virulence, cell death, antagonistic
bacteria