DNA extractions, PCR amplification and visualization
– Detection of major bacterial and fungal pathogens
– Sequencing targetted genes
– Experimental infections in semi controlled conditions
Diagnostic bactériens, champignons, nématodes, infections expérimentales en conditions semi-contrôlées
The molecular laboratory (former PV site) where DNA extractions and amplification by PCR are carried out. Biology
Developed each year since 2014 on two sites (lowlands of Banfora and irrigated perimeters of Karfiguela), these experimental plots situated within the agro-ecosystem enabling to conduct a pluri-annual monitory of the set of bio-aggressors (virus, bacteria, fungi, nematodes, insects and self-propagating plants) thanks to a collaborative work associating phytopathology, entomology and weed science.
Picture of the experimental plot of Banfora : four cultivars certified in Burkina Faso are placed in random blocks with weeding and herb planting treatment.
The structure of pathogen populations is studied with microsatellite markers for various Xanthomonas species (affecting rice, cassava or mango trees) or fungi, such as blast disease in rice.
Results show no genetic difference between the Xanthomonas citri pv. Mangiferaeindicae populations collected on a mango tree and a cashew tree.
The pathogenic data are in line with these genetic data, enabling to conclude on lack of host specialization with this bacteria species.
Zombre et al. (2016)
Results gathered in controlled conditions have shown that rice cultivars certified in Burkina Faso are resistant to Xanthomonas oryzae.
Field tests are ongoing in order to assess the sustainability of such resistances and to detect possible resistance breakdown events.
The use of plant extracts is another control method that has been studied. For example, the essential oil of Cymbopogon citratus inhibits the growth of Xanthomonas oryzae in vitro.
Wonni et al. (2016)
The results obtained on the interaction between the RYMV virus and Xoc bacteria in rice reveal that co-infection is frequent in the agro-ecosystem. Experimentally, a reciprocal effect was highlighted in a co-infection context, likely involving “RNA silencing” plant defense mechanism.
Tollenaere et al (2017)
Multiple disease epidemiological surveys (see: https://dataverse.ird.fr/dataset.xhtml?persistentId=doi:10.23708/8FDWIE ) and experimental approaches are carried out (see EVCOPAR project) in order to study the interactions between the different major rice pathogens.
The characterization bacterial and fungal communities associated with plants is performed by targeted detection, metabarcoding and microbiology approaches. The last approach (“culturomics”) enables to consider in vivo tests of micro-organisms studied to assess their potential bio-fertilizing and/or biocontrol properties.
Training
Top left and in center: a training on molecular biology for students (September 2016). Bottom left: a workshop on “Strategies for innovative control of bacterial diseases, based on knowledge on molecular mechanisms of interaction” (October 2017). On the right (top and bottom): a training on seed production for rice farmers.