Dataset and README file for detached roots paper Denarie et al.

Abstract
Background and Aims Plant pathogens are amongst the most serious biotic threats to crop production and food security. Silicon (Si) accumulation in plant tissues is widely reported to increase plant resistance to such pathogens via physical deposition and biochemical mechanisms; however, this is largely studied for shoot rather than root infections. We aimed to investigate whether Si supplementation at different levels enhances wheat root resistance to the fungal pathogen Bipolaris sorokiniana, a causal agent of root and crown rot. We focused on Si deposition as a physical resistance trait and macronutrients involved in plant defence signalling such as calcium (Ca) and sulphur (S).
Methods Wheat seedlings were grown hydroponically with varying Si supplementation levels (0mM, 0.25mM, 0.5mM, 2mM, and 4mM). Excised roots were then inoculated ex vivo with two B. sorokiniana isolates (84144 and 84145). Disease severity parameters (incubation period, root blackening, electrolyte leakage, and sporulation) were assessed alongside patterns of silica deposition in the roots and elemental concentrations.
Results Si supplementation increased Si accumulation and formed a continuous silica ring in the root endodermis but with concomitant decreases in Ca and S concentrations. Despite significant Si deposition in the roots, its impacts were limited to a decrease in B. sorokiniana sporulation, and the pathogen was largely able to colonize roots unimpaired.
Conclusion Our results suggest a limited role for Si-based physical defences against B. sorokiniana in wheat roots and that decreases in essential nutrients like Ca and S may further explain why root disease resistance was not enhanced. Biochemical pathways could be more important in Si mediated defence than the physical presence of Si alone.