Susceptibility Is New Resistance: Wheat Susceptibility Genes and Exploitation in Resistance Breeding

Abstract

Adapted pathogens and pests seriously threaten global wheat production. During pathogen and pest infections, wheat susceptibility (S) genes are exploited to support the compatibility of wheat with pathogens and pests. A plethora of wheat S genes were recently identified and revealed to regulate multiple processes, including pathogen (pre)penetration, plant immunity, pathogen sustenance, and pest feeding. The inactivation of some S genes via newly developed genome editing and TILLING techniques could reduce compatibility and confer broad-spectrum and durable resistance, which provide a new avenue for wheat resistance improvement. In this review, we summarized recent advances in the characterization of wheat S genes and highlighted their multifaceted roles in facilitating compatible interactions of wheat with adapted pathogens and pests. Current strategies, limitations, and future directions in exploiting S genes in wheat resistance breeding are discussed.

Integrative systems biology of wheat susceptibility to Fusarium graminearum uncovers a conserved gene regulatory network and identifies master regulators targeted by fungal core effectors

“…As a whole, 233 wheat genes (Additional file 1 : Table S5) targeted by F. graminearum effectors matched with known S genes [ 16 , 31 , 50 ], including 8 genes that were validated in the wheat— F. graminearum pathosystem [ 24 , 26 , 29 , 51 , 52 ]—and 183 genes that were associated with defense suppression. A total of 147 S genes were found to be part of the TF regulatory network of FHB responses, of which 41 were master TFs and 26 were TFs.…”

“…Merging the S genes database and the F. graminearum in planta targets, we identified 233 S genes putatively targeted by F. graminearum core nuclear effectors (Fig. 7 ), of which 64% were induced along with the infection progress and were proved to have a role in defense suppression with a wide range of mechanisms [ 16 , 31 , 50 ]. Interestingly, our integration approach shed light on 8 genes already validated as S genes in the wheat– F. graminearum pathosystem including the TaHRC gene that underlies the Fhb1 QTL [ 27 , 28 ] and that was induced in response to F. graminearum infection.…”

Genetics of Resistance to Leaf Rust in Wheat: An Overview in a Genome-Wide Level

“…Transgenic expression of clustered R gene cassette is another strategy to provide broad-spectrum resistance to multiple rust pathotypes [154]. Gene-editing on susceptible genes or negative regulatory genes of plant defense responses shows great potentials in improvement of wheat resistance to fungal diseases [155].…”

Genetics of Resistance to Leaf Rust in Wheat: An Overview in A Genome-Wide Level

“…Transgenic expression of clustered R gene cassette is another strategy to provide broad-spectrum resistance to multiple rust pathotypes [151]. On the other hand, geneediting on susceptible genes or negative regulatory genes of plant defense responses shows great potentials in improvement of wheat resistance to fungal diseases [152].…”