| Based on these groups the possible presence of Lr genes in these
varieties are presented in Table 4. The varieties
namely E 8643 and E 8667 showed reactions similar to those to alien gene/s
Lr9 and Lr19. On tracing their parantages the possibility
of these gene/s are rule out. However, the type of resistance given by these
varieties is expected by a combined action of two or more gene i.e.
Lr10 (Exe) + Lr15/or Lr10 (Exe) + Lr3 (Ka) +
Lr15/Lr16/Lr17 or Lr10 (Lee) + Lr15
+ Lr2 (any of the alleles) or Lr3. Gabo being one of the parent
in E 8643 indicated the presence of Lr10 (ANDERSON 1961, REDDY 1974),
wheat variety E 8667 has maintained resistant to leaf rust under Indian
conditions for many years (AGARWAL & PANDEY 1976). HS 1138-6-4 derived from Sonalika cross indicated the presence of Lr3 +Lr11 if additional genes providing resistance to virulences 162 and 104 are assumed. For the type of resistance showed by HB 117-107 a gene combination of Lr3 + Lr1 or Lr3 (Ka) + Lr2a is expected REDDY & RAO (1979) reported Lr3 + Lr15 in this variety. The resistance of V156 a derivative of Wiconsin 245 is covered by Lr2a. This variety though susceptible to many leaf rust virulences in seedling stage has maintained field resistance. The reactions of HD 2009 are comparable to Lr10 (Exe). However, a gene combination of Lr10 (Exe) + Lr23 + Lr2b/Lr2c/Lr2d may be responsible for imparting resistance to this variety. However, Gabo being one of the parent, the presence of Lr10 is evident in this variety. CPAN 1238 showed susceptible reaction to virulences 77 and 108 and its resistance is covered by a gene combination of Lr2 (any of the alleles) + Lr1 + Lr20. From its pedigree this variety appears to have genes from Lerma rojo 64 and Sonora 64. Presence of Lr1 is supported on account of Sonora 64. The work of GUPTA and SAINI (1980-1982), SAINI and GUPTA (1979) confirms it. CPAN 1436 (Tobari-66) resistance is covered by a combination of Lr1 + Lr2 (any of the alleles) + gene for resistance to 104 virulence of Lr1 + Lr12/Lr13/Lr14a/Lr21/Lr22 + genes for resistance to virulences 17 and 104. In either of these two combinations presence of Lr1 is evident which is in agreement with the compiled work of MCINTOSH 1973, GUPTA and SAINI (1980), (1982), SAINI and GUPTA (1979). |
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