Rust (fungus) of the rust fungi "Cronartium ribicola", preventing the formation of basidiospores which infect the primary host. Although spores from white pines cannot infect other white pines, survival spores may overwinter on infected pines and reinfect "Ribes" spp. the following season. Infected tissue is removed from white pines and strict quarantines of "Ribes" spp. are maintained in high risk areas. "Puccinia graminis" is a macrocyclic heteroecious fungus that causes wheat stem rust disease. The repeating stage in this fungus occurs on wheat and not the alternate host, barberry. The repeating stage allows the disease to persist in wheat even though the
Wheat leaf rust role in resistance breeding for cultivated crops. The earliest single resistance gene was identified as effective against yellow rust. Numerous single genes for leaf rust resistance have since been identified, the 47th genes prevent crop losses due to "Puccinia recondite" Rob. Ex Desm. f.sp. "tritici" infections, which can range from 5% to 15% depending on the stage of crop development. Leaf rust resistance gene is an effective adult-plant resistance gene that increases resistance of plants against "P. recondita" f.sp." tritici" (UVPrt2 or UVPrt13) infections, especially when combined with genes Lr13 and gene Lr34 (Kloppers & Pretorius, 1997). Lr37 originates from