Resistance to Wheat streak mosaic virus identified in synthetic wheat lines

Citation: Shoup Rupp, J. L., Simon, Z. G., Gillett-Walker, B., & Fellers, J. P. (2014). Resistance to Wheat streak mosaic virus identified in synthetic wheat lines. Retrieved from http://krex.ksu.eduWheat streak mosaic virus (WSMV) is an important pathogen in wheat that causes significant yield losses each year. WSMV is typically controlled using cultural practices such as the removal of volunteer wheat. Genetic resistance is limited. Until recently, no varieties have been available with major resistance genes to WSMV. Two resistance genes have been derived from Thinopyrum intermedium through chromosome engineering, while a third gene was transferred from bread wheat through classical breeding. New sources of resistance are needed and synthetic wheat lines provide a means of accessing genetic variability in wheat progenitors. A collection of wheat synthetic lines was screened for WSMV resistance. Four lines, 07-SYN-27, -106, -164, and -383 had significant levels of resistance. Resistance was effective at 18 °C and virus accumulation was similar to the resistant control, WGGRC50 containing Wsm1. At 25 °C, resistance was no longer effective and virus accumulation was similar to the susceptible control, Tomahawk

Two small secreted proteins from <i>Puccinia triticina</i> induce reduction of ß-glucoronidase transient expression in wheat isolines containing <i>Lr9, Lr24</i> and <i>Lr26</i>

<p>Little is known about the molecular interaction of wheat and leaf rust (<i>Puccinia triticina</i> Eriks). However, genomic tools are now becoming available so that the host–pathogen interactions can be better understood. Significant efforts are being placed on understanding the secretomes of various pathogens as secreted peptides are believed to be the best candidates for avirulence effectors. In this work, a <i>P. triticina</i> haustorial cDNA library was evaluated for the presence of proteins containing secretion signals. Ten predicted proteins were found in the library, of which two were expressed in haustorial fractions. Three of the secreted proteins, Pt3, Pt12 and Pt27, were used in biolistic experiments to determine whether they could induce hypersensitive cell death, which is commonly observed in incompatible rust interactions with wheat leaf rust resistance genes. When Pt3 was co-bombarded with a β-glucoronidase (GUS)-expressing vector into wheat isolines with resistance genes <i>Lr9</i> or <i>Lr24</i>, a significant reduction of GUS expression was observed, presumably due to hypersensitive cell death. In other co-bombardment experiments, Pt27 induced a significant reduction in GUS expression in the <i>Lr26</i> isoline. These results suggest that Pt3 and Pt27 may function in avirulence against wheat leaf rust in resistant genotypes.</p