Genetic base of durable resistance to Puccinia triticina of two Serbian varieties

Abstract

The durable resistant varieties were developed more than 15 years ago. The basis of the resistance was investigated at seedling stage according to reaction type (RT) at air temperatures 20-25°C. The F2 generations of varieties Anastasia or Selekta x Lr 1, Lr 2a, Lr 3, Lr 13, Lr 14a, Lr 16 or Lr 26 were tested with isolates producing low RT on first two mentioned Lr lines. The presence of these single resistant genes in the varieties was excluded by presence of susceptible plants in F2 progenies of adequate crosses. The resistant combinations were Lr 3+B as Lr3+C in Selekta and Lr26+E, Lr26+C as EC in Anastasia. According to lower infection efficiency and yellowing of the above tip top part the C was similar or Lr 34. The Lr 13 and 14a were near the same effective at seedlings when were added to proposed combinations in parents. According to F1 results in field the most effective over season combination was achieved by crossing the investigated varieties because of two LP prolong able complementary genes and accumulation of three infection severity responsible ones

10.5937/ratpov50-4482 = Functions of LR genes beside reduction of Puccinia triticina

“…Lower maximal intensity than on Thatcher was achieved by genes different positioned on chromosomes (McIntosh et al 1995;Purnhauser et al 2000). For confirmation of the above, recent dividing of Lr genes in two groups, the Lr 1 (5D) and Lr 2a (2D) genes were regional express able through lower RT at seedling stage to the particular races of pathogen (Boskovic & Browder 1976, Prijic & Jerkovic 2010, while generally most effective by RT decrease were Lr 19 (7D) and Lr 24 (3D) ( Jerkovic 1992); even chromosomes from D genome were described as suppressor genes containing (Dyck 1987, Nelson et al 1997. Lr 1 and Lr 19 were recently proved as such according to lower RT (Tables 2 and 3).…”

“…RAR values of Lr 1, Lr 15, Lr 19 were equal and distanced from Lr 22b line more than Lr 16, Lr 37 and Lr 29. The active sites of adequate enzymes could not be the same also confirmed by different RTs when mono pustule isolate of parasite was applied (Boskovic & Browder 1976, Jerkovic 1992, Bulos et al 2006, Winzeler et al 2000, Prijic & Jerkovic 2010. Simulated results when RAR values sum was equalized with seven defined those genes as responsible for 3 to 19% of root proteins lack.…”