Background and aims
The root surface of a plant usually exceeds the leaf area and is constantly exposed to a variety of soil-borne microorganisms. Root pathogens and pests, as well as belowground interactions with beneficial microbes, can significantly influence a plants' performance. Unfortunately, the analysis of these interactions is often limited because of the arduous task of accessing roots growing in soil. Here, we present a soil-free root observation system (SF-ROBS) designed to grow maize (Zea mays) plants and to study root interactions with either beneficial or pathogenic microbes.
The SF-ROBS consists of pouches lined with wet filter paper supplying nutrient solution.
The aspect of maize grown in the SF-ROBS was similar to soil-grown maize; the plant growth was similar for the shoot but different for the roots (biomass and length increased in the SF-ROBS). SF-ROBS-grown roots were successfully inoculated with the hemi-biotrophic maize fungal pathogen Colletotrichum graminicola and the beneficial rhizobacteria Pseudomonas putida KT2440. Thus, the SF-ROBS is a system suitable to study two major belowground phenomena, namely root fungal defense reactions and interactions of roots with beneficial soil-borne bacteria.
This system contributes to a better understanding of belowground plant microbe interactions in maize and most likely also in other crops.
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soil-free root observation system
maize nutrient solution
green fluorescent protein
day(s) post infection
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We thank Natacha Fleury and Daniela Villacres de Papajewski for their technical help, Christophe Weider (Syngenta Crop Protection) for technical advices and Felix Mauch for critical reading of the manuscript. Partial funding of this project by the National Center of competence in Research, Plant Survival, is gratefully acknowledged.
Chantal Planchamp and Dirk Balmer contributed equally.
Responsible Editor: Bernard Glick.
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Planchamp, C., Balmer, D., Hund, A. et al. A soil-free root observation system for the study of root-microorganism interactions in maize. Plant Soil 367, 605–614 (2013). https://doi.org/10.1007/s11104-012-1497-8
- Zea mays
- Root infection
- Colletotrichum graminicola
- Pseudomonas putida