Influence of rhizobacterial volatiles on the root system architecture and the production and allocation of biomass in the model grass Brachypodium distachyon (L.) P. Beauv.

BMC Plant Biology

Research Article

Stijn Spaepen¹  Yves Brostaux²  Benjamin M. Delory³  Magdalena Mendaluk-Saunier de Cazenave³  Caroline Baudson³  Sébastien Varin³  Pierre Delaplace³  Patrick du Jardin³ 

[1] Department of Plant Microbe Interactions, Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, 50829, Köln, Germany;University of Liège, Gembloux Agro-Bio Tech, Applied Statistics, Computer Science and Modeling, Passage des Déportés 2, 5030, Gembloux, Belgium;University of Liège, Gembloux Agro-Bio Tech, Plant Biology, Passage des Déportés 2, 5030, Gembloux, Belgium;

关键词: Biomass Production;    Adventitious Root;    Total Root Length;    Bacillus Pumilus;    Root System Architecture;   

DOI  :  10.1186/s12870-015-0585-3

 received in 2015-05-06, accepted in 2015-08-03,  发布年份 2015

来源: Springer

【 摘 要 】

BackgroundPlant growth-promoting rhizobacteria are increasingly being seen as a way of complementing conventional inputs in agricultural systems. The effects on their host plants are diverse and include volatile-mediated growth enhancement. This study sought to assess the effects of bacterial volatiles on the biomass production and root system architecture of the model grass Brachypodium distachyon (L.) Beauv.ResultsAn in vitro experiment allowing plant-bacteria interaction throughout the gaseous phase without any physical contact was used to screen 19 bacterial strains for their growth-promotion ability over a 10-day co-cultivation period. Five groups of bacteria were defined and characterised based on their combined influence on biomass production and root system architecture. The observed effects ranged from unchanged to greatly increased biomass production coupled with increased root length and branching. Primary root length was increased only by the volatile compounds emitted by Enterobacter cloacae JM22 and Bacillus pumilus T4. Overall, the most significant results were obtained with Bacillus subtilis GB03, which induced an 81 % increase in total biomass, as well as enhancing total root length, total secondary root length and total adventitious root length by 88.5, 201.5 and 474.5 %, respectively.ConclusionsThis study is the first report on bacterial volatile-mediated growth promotion of a grass plant. Contrasting modulations of biomass production coupled with changes in root system architecture were observed. Most of the strains that increased total plant biomass also modulated adventitious root growth. Under our screening conditions, total biomass production was strongly correlated with the length and branching of the root system components, except for primary root length. An analysis of the emission kinetics of the bacterial volatile compounds is being undertaken and should lead to the identification of the compounds responsible for the observed growth-promotion effects. Within the context of the inherent characteristics of our in vitro system, this paper identifies the next critical experimental steps and discusses them from both a fundamental and an applied perspective.

【 授权许可】

CC BY   
© Delaplace et al. 2015