AUTHOR=Cowger Christina , Ward Brian , Brown-Guedira Gina , Brown James K. M. 

TITLE=Role of Effector-Sensitivity Gene Interactions and Durability of Quantitative Resistance to Septoria Nodorum Blotch in Eastern U.S. Wheat

JOURNAL=Frontiers in Plant Science

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2020.00155

DOI=10.3389/fpls.2020.00155

ISSN=1664-462X

ABSTRACT=<p>Important advances have been made in understanding the relationship of necrotrophic effectors (<italic>NE</italic>) and host sensitivity (<italic>Snn</italic>) genes in the <italic>Parastagonospora nodorum</italic>-wheat pathosystem. Yet much remains to be learned about the role of these interactions in determining wheat resistance levels in the field, and there is mixed evidence on whether breeding programs have selected against <italic>Snn</italic> genes due to their role in conferring susceptibility. SNB occurs ubiquitously in the U.S. Atlantic seaboard, and the environment is especially well suited to field studies of resistance to natural <italic>P. nodorum</italic> populations, as there are no other important wheat leaf blights. Insights into the nature of SNB resistance have been gleaned from multi-year data on phenotypes and markers in cultivars representative of the region’s germplasm. In this perspective article, we review the evidence that in this eastern region of the U.S., wheat cultivars have durable quantitative SNB resistance and <italic>Snn–</italic>NE interactions are of limited importance. This conclusion is discussed in light of the relevant available information from other parts of the world.</p>