The transcription factor TCP9 regulates responses in root architecture to the beet cyst nematode Heterodera schachtii in Arabidopsis thaliana

Low levels of infection by cyst nematodes on some resistant crop varieties result in significant loss in yield, while other heavily infected susceptible varieties show hardly any symptoms at all. This suggests that some plants tolerate biotic stress by plant parasitic nematodes better than others. We hypothesize that tolerant plants accommodate nematode infections by altering the architecture of their root system. Our current objective is to investigate whether the transcription factors TCP9 and TCP20, which are known regulators of plant root architecture, are involved in tolerance to cyst nematodes in Arabidopsis. To this end, we first tested whether TCP9 and TCP20 regulate susceptibility of Arabidopsis to the beet cyst nematode Heterodera schachtii. Next, we analysed the root architecture of nematode-infected roots of Arabidopsis tcp9 and tcp20 knock-out mutants to assess whether these genes are involved in alterations in primary and secondary roots associated with nematode infections. Finally, we tested whether tcp9 and tcp20 mutants are less sensitive for methyl jasmonate, which is required for the recovery of damaged plant tissue after host invasion by nematodes. Altogether, our data demonstrates that TCP9 regulates responses in root architecture in Arabidopsis to H. schachtii.