RPS2 and infection: Group I, II and III mutants were tested for resistance mediated by the TNL pair RRS1 and RPS4 (TNLRRS1–RPS4) to Pst avrRps4 infection in leaves, measured against wild-type Col-0 (Col, resistant), an rrs1a rrs1b (rrs1ab) mutant defective specifically in TNLRRS1–RPS4 ETI36, as well as eds1 and an a3 n2 ‘helperless’ mutant which are both fully susceptible to Pst avrRps412,19,25,26.