The application of molecular markers for wheat improvement:
Kokhmetova, A.
The application of molecular markers for wheat improvement: Breeding for stem rust resistance in Kazakhstan - Mexico, DF (Mexico) CIMMYT : 2011 - p. 35
Abstract only
Wheat rusts are important problems in Kazakhstan and one of the major factors reducing the productivity of this crop. Of the three rusts, stem rust of wheat is one of the most damaging diseases of wheat throughout the world. Recently, a virulent race of stem (Puccinia graminis Pers.f.sp.tritici) designated Ug99, ?TTKS?, resulted in the break down of stem rust resistance gene, Sr31 which is widely deployed and found in most wheat varieties grown around the world. Since then, TTKS variants with virulence to other stem rust genes including Sr24, Sr36, etc has been reported posing serious threat to wheat production worldwide. Unlike other rusts, which only partially affect wheat yields, stem rust can cause up to 100% crop loss. Up to 80 per cent of all Asian and African wheat varieties are susceptible to the fungus and major wheat-producing nations to Iran?s east ? such as Afghanistan, India, Pakistan, Turkmenistan, Uzbekistan and Kazakhstan ? should be on high alert FAO (2008) warned. Host resistance remains one of the most cost effective control measures. Thus knowledge of the genes present in current elite cultivars is imperative if effective breeding strategies are to be employed in combating the potential losses associated with break down in stem rust resistance. The aim of the present study was to screen elite advanced wheat lines from Kazakhstan with markers linked to stem rust genes Sr22, Sr24, Sr25, Sr26, and Sr39 including the adult plant yellow rust resistance gene Yr18/Lr34. We also evaluated a wide range of wheat lines from various parts of the world against number races of Puccinia graminis Pers. collected in different part of Kazakhstan. Eight out of 42 genotypes possess Sr22 and displayed DNA fragment associated with Sr22 resistant gene. None of the lines possess Sr25, Sr26 and Sr39. However, 7 lines displayed DNA-fragment associated with Sr24 resistance when amplified with STS primer Sr24#12. A high number of the lines, 25 out of 42 possess yellow rust resistance gene Yr18/Lr34. Four of the lines have combined Sr24 and Yr18 stem and yellow rust resistance genes. These results would assist breeders in choosing parents for crossing in developing varieties with desirable levels of stem rust resistance in Kazakhstan.
English
978-970-648-179-5
The application of molecular markers for wheat improvement: Breeding for stem rust resistance in Kazakhstan - Mexico, DF (Mexico) CIMMYT : 2011 - p. 35
Abstract only
Wheat rusts are important problems in Kazakhstan and one of the major factors reducing the productivity of this crop. Of the three rusts, stem rust of wheat is one of the most damaging diseases of wheat throughout the world. Recently, a virulent race of stem (Puccinia graminis Pers.f.sp.tritici) designated Ug99, ?TTKS?, resulted in the break down of stem rust resistance gene, Sr31 which is widely deployed and found in most wheat varieties grown around the world. Since then, TTKS variants with virulence to other stem rust genes including Sr24, Sr36, etc has been reported posing serious threat to wheat production worldwide. Unlike other rusts, which only partially affect wheat yields, stem rust can cause up to 100% crop loss. Up to 80 per cent of all Asian and African wheat varieties are susceptible to the fungus and major wheat-producing nations to Iran?s east ? such as Afghanistan, India, Pakistan, Turkmenistan, Uzbekistan and Kazakhstan ? should be on high alert FAO (2008) warned. Host resistance remains one of the most cost effective control measures. Thus knowledge of the genes present in current elite cultivars is imperative if effective breeding strategies are to be employed in combating the potential losses associated with break down in stem rust resistance. The aim of the present study was to screen elite advanced wheat lines from Kazakhstan with markers linked to stem rust genes Sr22, Sr24, Sr25, Sr26, and Sr39 including the adult plant yellow rust resistance gene Yr18/Lr34. We also evaluated a wide range of wheat lines from various parts of the world against number races of Puccinia graminis Pers. collected in different part of Kazakhstan. Eight out of 42 genotypes possess Sr22 and displayed DNA fragment associated with Sr22 resistant gene. None of the lines possess Sr25, Sr26 and Sr39. However, 7 lines displayed DNA-fragment associated with Sr24 resistance when amplified with STS primer Sr24#12. A high number of the lines, 25 out of 42 possess yellow rust resistance gene Yr18/Lr34. Four of the lines have combined Sr24 and Yr18 stem and yellow rust resistance genes. These results would assist breeders in choosing parents for crossing in developing varieties with desirable levels of stem rust resistance in Kazakhstan.
English
978-970-648-179-5