The wheat–Septoria conflict: a new front opening up?

• Fungicide-resistant/insensitive strains of Zymoseptoria tritici are widespread.
• Availability of Z. tritici-resistant wheat germplasm is limited.
• We examine the impact of novel genomics technologies on addressing this issue.

In the utopic absence of abiotic and/or biotic stressors, attaining the predicted increase (up to 70%) in wheat demand by 2050 in response to global population trends is a challenge. This objective becomes daunting, however, when one factors in the continuous constraint on global wheat production posed by Septoria tritici blotch (STB) disease. This is because, despite resistant loci being identified, a deficit of commercially relevant STB-resistant wheat germplasm remains. The issue is further compounded for growers by the emergence and prevalence of fungicide-resistant/insensitive strains of the causative pathogen Zymoseptoria tritici (formerly known as Mycosphaerella graminicola/Septoria tritici). However, biotechnology-based research is providing new opportunities in this struggle. As the exome response of wheat to STB attack begins to be deciphered, genes intrinsic to resistant and susceptible phenotypes will be identified. Combined with the application of genome-editing techniques and a growing appreciation of the complexity of wheat's and the dynamism of Z. tritici's genome, the generation of resulting STB-resistant wheat varieties will counter the prevalent threat of STB disease in wheat-production systems.