TITLE:
Phenotypic and Molecular Characterization of Wheat Leaf Rust Resistance Gene Lr34 in Iranian Wheat Cultivars and Advanced Lines
AUTHORS:
Seyed Taha Dadrezaei, Kumarse Nazari, Farzad Afshari, Ebrahim Mohammadi Goltapeh
KEYWORDS:
Lr34 Gene; AUDPC; Salinity Stress; Leaf Rust; Puccinia triticina
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.4 No.9,
August
29,
2013
ABSTRACT: Lr34 is a vital gene in
developing resistance to leaf rust, stripe rust, and powdery mildew of wheat.
Providing simultaneous resistance to various pathogens has made this gene
valuable in breeding for wheat resistance to many diseases. The present study investigates the csLV34 marker’s capability in diagnosing this locus in130 wheat
commercial cultivars and advanced wheat lines from Iran, and assesses the impact of this gene
on disease severity in field conditions. To assess the reactions of
cultivars and lines which contained Lr34 under epidemic conditions of leaf rust, these cultivars
were cultivated during the 2009 and 2010 cropping season. Of the 130 studied
cultivars, 43 contained Lr34. Cultivars that were selected
and studied in stress conditions had the most frequent presence of Lr34.
It can be concluded that this gene plays a vital role in increasing the
tolerance of cultivars under stress conditions. Lr34 seems to cause active transition of materials
out of the cell. In addition to being resistant to several important diseases
of wheat, Lr34 can increase tolerance to
stresses such as salinity. Considering the calculated value for AUDPC (3%-440%/d) in
cultivars containing Lr34, it seems that some cultivars
contained additional resistance genes. The rate of infection in all cultivars,
when presence of Lr34 was detected through the molecular
marker, was lower than in other cultivars. Field results confirmed the results
of the analysis using the csLV34b molecular marker.