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Resistance gene homologues were isolated from finger millet (Eleusine coracana L.) using degenerate oligonucleotide primers designed to the conserved regions of the nucleotide binding site (NBS) of previously cloned plant disease resistance genes (R-genes) using polymerase chain reaction (PCR). Of the eleven primer combinations tested, only five showed amplification of resistance gene homologues in finger millet. BLAST search of cloned finger millet DNA fragments showed strong homology to NBS-LRR-type R-genes of other crop species. Of the 107 clones sequenced, 41 showed homology to known R-genes, and are denoted as EcRGHs (Eleusine coracana resistance gene homologues), while 11 showed homology to pollen signalling proteins (PSiPs), and are denoted as EcPSiPs (Eleusine coracana pollen signalling proteins). The cloned EcRGH sequences were classified into four clusters, and EcPSiPs formed two separate clusters based on sequence homology at the amino acid level. The amino acid sequences of the cloned EcRGHs showed characteristic features of non-TIR-type R-genes, which have been identified in all the monocot species studied so far. Six EcRGHs-specific primers were designed based on the sequences obtained in finger millet; reverse transcription PCR was performed on the cDNA and revealed the expression of EcRGHs in finger millet. The ratio of non-synonymous to synonymous nucleotide substitution (dN/dS) in the NBS domains of finger millet RGHs varied from 0.3 to 0.7 for the different classes, which suggests a purifying selection, though the LRR region also needs to be considered to make predictions. This is the first report on RGHs in finger millet, which will serve as a valuable resource for finger millet improvement using molecular tools.

Gene PmAF7DS confers resistance to wheat powdery mildew (isolate Bgt#211 ); it was mapped to a 14.6-cM interval ( Xgwm350 a- Xbarc184 ) on chromosome 7DS. The flanking markers could be applied in MAS breeding. Wheat powdery mildew (Pm) is caused by the biotrophic pathogen Blumeria graminis tritici (DC.) (Bgt). An ongoing threat of breakdown of race-specific resistance to Pm requires a continuous effort to discover new alleles in the wheat gene pool. Developing new cultivars with improved disease resistance is an economically and environmentally safe approach to reduce yield losses. To identify and characterize genes for resistance against Pm in bread wheat we used the (Arina × Forno) RILs population. Initially, the two parental lines were screened with a collection of 61 isolates of Bgt from Israel. Three Pm isolates Bgt#210 , Bgt#211 and Bgt#213 showed differential reactions in the parents: Arina was resistant (IT = 0), whereas Forno was moderately susceptible (IT = -3). Isolate Bgt#211 was then used to inoculate the RIL population. The segregation pattern of plant reactions among the RILs indicates that a single dominant gene controls the conferred resistance. A genetic map of the region containing this gene was assembled with DNA markers and assigned to the 7D physical bin map. The gene, temporarily designated PmAF7DS, was located in the distal region of chromosome arm 7DS. The RILs were also inoculated with Bgt#210 and Bgt#213. The plant reactions to these isolates showed high identity with the reaction to Bgt#211, indicating the involvement of the same gene or closely linked, but distinct single genes. The genomic location of PmAF7DS, in light of other Pm genes on 7DS is discussed.

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