Lineage Exclusion Principle-A Tool For Rational Deployment Of Rice Blast Resistance Genes Rasool Farahanaz Online published on 15 December, 2016. Abstract To rationalize the choice of genes in résistance breeding programme, the study of closely related or clonal isolate groups or lineages having restricted virulence patterns has been undertaken (Levey et al., 1993; Zeigler et al., 1994; Roumen et al., 1997; Rathour et al., 2004). In Japan, two sets of differential varieties (DV's) targeting 13 resistance genes-Pia, Pib, Pii, Pik, Pik-5, Pik-p, Pik-h, Pik-m, Pit, Pita, Piz, Pita-2 and Piz-1-have been developed and used widely in different countries; at IRRI, a set of near isogenic lines (NILs) in ‘Co-39’ Indica type background having four resistance genes was developed; in China, a set of NILswith five resistance genes-Pib, Pik, Pik-m, Pik-p and Pita-2-was developed, whereas in Japan, 32 disease resistance genes were incorporated in a susceptible Japonica type variety Lijangxintuanheigu ‘LTH’ (Inukai et al., 1999; Kumar et al., 2007). The comparative results indicated that these differential varieties in each study couldexplain wide variations of pathotypes in the test population and demonstrate the differential abilities of the pathogen (Zeigler et al., 1994). Top Keywords Lineage Exclusion, Rice blast, Differentials, virulence. Top |