University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Doctoral Thesis:
Abdul Samad
(2017):
Investigations of the structure, function and herbicidal potential of bacterial communities associated with grapevine and vineyard weeds.
Doctoral Thesis - Institut für Bodenforschung (IBF),
BOKU-Universität für Bodenkultur,
pp 141.
UB BOKU
obvsg
- Abstract:
- Vineyards harbor a variety of weeds, which are usually controlled since they compete with grapevines for water and nutrients. However, weeds may host a wide variety of microorganisms that interact with grapevine, having beneficial, neutral or phytopathogenic effects. To study our hypothesis that weeds and grapevine plants growing on same soil share some microorganisms, but microbial community structure and functionalities might be different, we investigated the microbiota associated with roots and rhizospheres of grapevine and four different weeds within a vineyard using 16S rRNA gene sequencing. Microbiome data analysis revealed that the weeds hosted significantly different structures of microbial community compared to grapevine plants in the rhizosphere as well as in root compartment, while in root compartment differences were more striking. The grapevine and weeds shared a few highly abundant operational taxonomic units (OTUs) across plants and compartments. Using cultivation, 500 rhizosphere bacteria and root endophytes were isolated, characterized and identified from Lepidium draba L. and grapevine. Weed-associated bacteria were found dominant in most of the functional characters tested in this study. Furthermore, we tested selected rhizobacteria and root endophytes for their herbicidal activity. An endophytic strain, CDRTc14, exhibited the most promising herbicidal activity against its host L. draba. To understand the possible genetic determinants of CDRTc14 herbicidal traits and plant interaction, whole genome sequencing was performed. Comparison with other Pseudomonas viridiflava genomes revealed several unique genes in the CDRTc14 genome particularly, related to stress tolerance and plant-microbe interactions. This study shows that there is a huge yet untapped potential of bacteria associated with weeds, which may influence the structure of crop microbiomes resulting in different functioning. Moreover, this research provides the basis for designing new strategies for weed control.
- Betreuer:
- 1. Berater: Steinkellner Siegrid