Research

Research

The Phytopathology unit focuses on the biology and impact of fungal and bacterial plant pathogens

Current projects

 Jolien Claerbout

Belgium is known for its lettuce produced on an intensive scale. The intensive production leads to an increased incidence of soil-borne pathogens, which are mainly controlled by chemicals. The use of chemicals should be reduced because of environmental considerations. Our project ‘FUNSLA’ aims to develop an integrated pest management strategy against soil-borne fungi and nematodes in leafy vegetables in the glasshouse. This research occurs in collaboration with ILVO and the practical research institutes in Kruishoutem (PCG), Sint-Katelijne-Waver (PSKW) and Rumbeke-Beitem (Inagro). We mainly assess the activity and management of basal rot pathogens (Rhizoctonia solani, Botrytis cinerea, Pythium spp. and Sclerotinia spp.). Special focus is given to Fusarium oxysporum f.sp. lactucae, which causes big problems in lettuce productions areas since 2015 and for which no control measures are available. We investigate different techniques to tackle this disease (e.g. biocontrol agents and soil disinfestation) and characterize the causal pathogen.

 

Feyisara Eyiwumi Oni investigates the diversity of fluorescent Pseudomonas spp and cyclic lipopeptides (CLPs) associated with the rhizosphere of the tropical cocoyam (Xanthosoma sagittifolium) crop.  Current studies include the use of CLP-producing Pseudomonads in the biological control of several plant pathogens including (i) Fusarium wilt pathogens on lettuce and banana and, (ii) Verticillium wilt of Pepper caused by Verticillium dahliae. Furthermore, modes of action of Pseudomonas spp. via cyclic lipopeptide and other pathways are explored.

 

Enrico Ferrarini

Bacillus and Pseudomonas bacteria are effective biocontrol agents in several crop species. Recent studies have increased the attention on the role of some secondary metabolites produced by these bacteria, called cyclic lipopeptides (CLPs), in triggering the defenses of the plants and on their direct effect against a number of pathogens. Our research is fulfilled in the context of the RHIZOCLIP consortium, which is aiming to unveil the ecological role of CLPs. In particular, we are focusing on the ability of CLPs to induce systemic resistance and to trigger transcriptomic and metabolomic alteration in roots and cell suspensions. We are testing the effect of selected pure CLPs in a number of pathosystems and aim to identify the molecular pathways involved in the defense response.

 

Lisa Heyman

Together with 15 partners of the European VitiSmart project, we want to contribute to a more sustainable viticulture. Viticulture is booming in Belgium. Our climate is a driving factor for epidemics of grapevine downy mildew, caused by Plasmopara viticola, which leads to serious losses in vineyards. The input of fungicides in vineyards could be significantly reduced by combining resistant cultivars with beneficial microorganisms. To improve breeding for resistance, our research aims to deepen the understanding of the aggressiveness of P. viticola. This will be achieved by studying differential interactions between P. viticola isolates and grapevine cultivars with different resistance loci. The other main objective of this research is to determine the biocontrol potential of cyclic lipopeptide (CLP)-producing fluorescent Pseudomonas strains against this pathogen. The tripartite interaction between both bacteria and CLPs, plant and pathogen is investigated further on the plant and on the pathogen side.

 

Van Bach Lam

Acid sulphate soils (ASSs) are characterized as soils with pH values below 4, phosphate deficiency and high aluminium and iron concentrations due to the oxidation of sulphide minerals in soils (Dent & Pons 1995). About 2.6 million hectares are found in Vietnam, corresponding to 11.76% and 30.77% of all ASSs in the world and in Asia respectively, and most of these soils are cultivated with rice plants. Rice cultivation in ASSs usually leads to a higher disease pressure and a reduced yield and grain quality. Therefore, Vietnamese farmers have excessively been applying inorganic fertilizers and fungicides for soil amendment and disease control. In order to progress to a sustainable biological agriculture, our research aims to characterize indigenous bacteria able to enhance the yield of low-land rice on these soils. Indigenous bacterial strains are being isolated, identified and tested on rice plants grown on acid sulphate soils. The main goal is to identify bacteria that can be used as bio-fertilizers, due to their ability to fix nitrogen and solubilize phosphorous, and as biocontrol agents against common rice pathogens.

 

Shirley Marcou

Vascular pathogens such as Verticillium and Fusarium species are causing wilt diseases worldwide in a wide range of crops. Shirley Marcou, next to her tasks as the professor’s assistant, carries out more fundamental research to determine how these species can survive and adapt their lifestyle in the xylem, which is a nutritionally poor environment.

 

Lijuan Meng

Strawberry gray mold, caused by Botrytis cinerea, is one of the most important airborne diseases of strawberry. The fungal pathogen infects the leaves and flowers of strawberry plants and subsequently resulting in fruit rot when the fruit begins to ripen, thus resulting in poor fruit quality and serious yield loss. Light is not only an essential energy source for plant, but also one of the most important environmental factors that govern plant growth and development including host defensive mechanisms. Host resistance in plants is an ideal biological defense against pathogens, and light of different wavelengths play important roles in plant host defense systems. My project aims to identify the antioxidative response of strawberry submitted to different light qualities and if these antioxidative responses have a role in plant-defence mechanisms against the necrotrophic pathogen Botrytis cinerea.

 

Olumide Owolabi Omoboye carries out research on fluorescent Pseudomonas obtained and characterized from the rhizosphere of cocoyams grown in a disease-suppressive soil in Cameroon, and disease-conducive soils from Cameroon and Nigeria. Taxonomic characterization revealed that the cocoyam rhizosphere in the disease suppressive soil was enriched with a high abundance of cyclic lipopeptide (CLP)-producing P. fluorescens complex isolates, and a high CLP diversity, while isolates obtained from the disease-conducive soils were mainly associated with the P. putida group coupled with a lower proportion of CLP-producing strains and lower CLP diversity. The isolates displayed excellent biocontrol activity (comparable to the versatile Pseudomonas sp. CMR12a) against Pythium myriotylum the causative organism of cocoyam root rot disease. The research focuses on the determination of the biocontrol potential of these isolates against Magnaporthe oryzae on rice, and Rhizoctonia solani on bean. Influence of soil quality and age on Pseudomonas species and CLP diversity will be investigated.

 

Kaat Peeters

For many years, rice sheath rot has been considered as a minor and geographically limited disease. Recently, however, the disease gained momentum and became widespread, causing significant yield losses worldwide. The major causal agent of sheath rot is the poorly studied fungal pathogen Sarocladium oryzae. In order to understand how this pathogen can be this successful, we aim to elucidate its mode of action. Therefore we study both the pathogen, its host and their interaction at different stages of the infection process. Because Sarocladium oryzae is often associated with bacteria, we aim to unravel the nature of this interaction and its importance in the rice sheath rot disease complex.