CPAN 1437 (Ariana-66) showed resistance to all leaf rust virulences excpet 12. A gene combination of Lr3 (Ka) + Lr10 (Exe) + Lr16 or Lr3 + Lr10 (Lee) + Lr21 is postulated in this variety. In CPAN 1438 an Australian line, gene combination of Lr10 (Exe) + Lr16 or Lr3 + Lr10 (Exe)/Lr10 (Lee) + Lr16 or Lr2b/Lr2c/Lr2d with some additional factors to impart resistance against virulence 162A is expected.

The resistance of CPAN 1517 (Colotana) is possibly covered by two or three gene combination i.e. Lr1 + Lr15 + Lr2 or Lr3 + Lr3 (Ka) + Lr17 or Lr3 + Lr15/Lr1+Lr3 plus additional factor responsible for resistance to virulence 104. These possible combinations suggest the presence of Lr1, Lr3 and Lr15.

The resistance of CPAN 1533 is comparable with gene combination of Lr15 + Lr3(Ka) or Lr15 + Lr16/Lr17/Lr20/Lr21/Lr23. From its pedigree (CC x Tob²), it is evident that Lr3 is present in this variety because both its parents carry this gene. The presence of Lr15 requires further detailed studies by genetic analysis.

References

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REDDY, M.S.S. and M.V. RAO. 1977. Genetic classification and control of leaf rust pathogen of wheat in India. Proc. 1st Nat. Sem. Genetics and Wheat Improvement, Ludhiana 78: 85.

SAINI. R.G. and A.K. GUPTA. 1979. Genes for resistance to brown rust (Puccinia recondita) in wheat II. Lr. genes in Frontana WG. 138 and E 6360, Cereal Res. Commu. 7(4): 289-91.