We showed that constitutive and inducible chemical and morphological defenses against Western flower thrips differ between tomato and chrysanthemum plants. Furthermore, we demonstrated that both... Show moreWe showed that constitutive and inducible chemical and morphological defenses against Western flower thrips differ between tomato and chrysanthemum plants. Furthermore, we demonstrated that both plant species respond differently to bacteria-derived defense elicitors, such as the phytotoxin coronatine. This highlights the plant species-specificity of these interactions and the possible limitation for the use of pathogen-associated molecular patterns to enhance the plant immune system. This study thus provides knowledge and novel strategies for Western flower thrips control. Yet, further comprehensive work is needed to evaluate the influence of these induction strategies on plant fitness. Show less
Plants and soils from natural ecosystems harbor great diversity of soil microorganisms, which could potentially contribute to the sustainability of horticulture. The knowledge about using wild... Show morePlants and soils from natural ecosystems harbor great diversity of soil microorganisms, which could potentially contribute to the sustainability of horticulture. The knowledge about using wild plant species and soil from natural ecosystem to improve the crop health will advance the application of ecological knowledge in horticulture. In this thesis, I evaluate the possibilities of using wild plant species and grassland soil to enhance the growth and reduce the disease susceptibility of chrysanthemum through plant-soil feedback principles. Grass-conditioned inocula contributed more to chrysanthemum growth than forb- or legume-conditioned inocula, this also lead to better chrysanthemum performance under Pythium treatment. Moreover, by mixing two plant-conditioned inocula, they interacted synergistically in terms of plant health but antagonistically in terms of plant growth. The influence of plant-conditioned inocula on chrysanthemum were still significant after two successive growth cycles, but their effects tended to converge because of the overriding effect of chrysanthemum growth. Inoculating greenhouse soil conditioned by wild plant species or grassland soil to greenhouse soil did not significantly improve the negative effects of greenhouse soil on chrysanthemum growth. Olpidium brassicae was identified as a main fungal pathogen of chrysanthemum when growing in greenhouse soil. Show less
