In hexaploid wheat, leaf rust resistance gene Lr1 is located at the distal end of the long arm of chromosome 5D. To clone this gene, an F1-derived doubled haploid population and a recombinant inbred line population from a cross between the susceptible cultivar AC Karma and the resistant line 87E03-S2B1 were phenotyped for resistance to Puccinia triticina race 1-1 BBB that carries the avirulence gene Avr1. A high-resolution genetic map of the Lr1 locus was constructed using microsatellite, resistance gene analog (RGA), BAC end (BE), and low pass (LP) markers. A physical map of the locus was constructed by screening a hexaploid wheat BAC library from cultivar Glenlea that is known to have Lr1. The locus comprised three RGAs from a gene family related to RFLP marker Xpsr567. Markers specific to each paralog were developed. Lr1 segregated with RGA567-5 while recombinants were observed for the other two RGAs. Transformation of the susceptible cultivar Fielder with RGA567-5 demonstrated that it corresponds to the Lr1 resistance gene. In addition, the candidate gene was also confirmed by virus-induced gene silencing. Twenty T 1 lines from resistant transgenic line T 0-938 segregated for resistance, partial resistance and susceptibility to Avr1 corresponding to a 1:2:1 ratio for a single hemizygous insertion. Transgene presence and expression correlated with the phenotype. The resistance phenotype expressed by Lr1 seemed therefore to be dependant on the zygosity status. T 3-938 sister lines with and without the transgene were further tested with 16 virulent and avirulent rust isolates. Rust reactions were all as expected for Lr1 thereby providing additional evidence toward the Lr1 identity of RGA567-5. Sequence analysis of Lr1 indicated that it is not related to the previously isolated Lr10 and Lr21 genes and unlike these genes, it is part of a large gene family.
Plant Molecular Biology – Springer Journals
Published: Jul 5, 2007
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera