Dear Editor,
Wheat is one of the most important staple food crops.Leaf rust caused by Puccinia triticina Eriks.(Pt) is a destructive foliar dis-ease that threatens world wheat production.Complementary wheat genes Necrosis 1 (Ne1) and Necrosis 2 (Ne2) on chromo-some arms 5BL and 2BS,respectively,cause hybrid necrosis(Caldwell and Compton,1943;Chu et al.,2006).Ne2 shows extremely tight genetic linkage with leaf rust resistance gene Lr13 (Zhang et al.,2016).We previously identified a temperature-sensitive leaf rust resistance gene LrZH22 in Chi-nese wheat cultivar Zhoumai 22 (ZM,Figure 1A) that was effective against most Chinese Pt pathotypes (Wang et al.,2016) and shared an overlapping genetic interval with Lr13.In a separate study,a recessive early leaf senescence 1 (els1)gene (Figure 1B) shared an overlapping interval with LrZH22/Lr13/Ne2 (Chu et al.,2006;Wang et al.,2016;Zhang et al.,2016;Li et al.,2018).However,the function and relationship of LrZH22/Lr13/Ne2/els1 remained unknown for decades.Here,we report the map-based cloning of LrZH22 and els1 and characterize their relationship with Lr13 and Ne2 in conjunction with a companion paper (Hewitt et al.,2021) studying the same gene.