Necmi  Beser¹ , Marilyn M. Del  Valle ² , Suk-Man  Kim² , Ricky B. Vinarao² , Halil Surek³ , Kshirod K. Jena²

1 Trakya University, Plant Breeding Research And Application Center, Edirne, Turkey, and Trakya University Havsa Vocational School, 22500 Havsa / Edirne, Turkey
2 Novel Gene Resources Laboratory, Plant Breeding Division, International Rice Research Institute, DAPO Box 7777, 1226 Metro Manila, Philippines
3 Trakya Agricultural Research Institute, P. Box 16, 22100, Edirne, Turkey
Author    Correspondence author
Molecular Plant Breeding, 2016, Vol. 7, No. 33   doi: 10.5376/mpb.2016.07.0033
Received: 16 May, 2016    Accepted: 01 Jul., 2016    Published: 18 Sep., 2016

This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Beşer N., Del Valle M.M., Kim S.M., Vinarao R.B., Sürek H., and Jena K.K., 2016, Marker-assisted Introgression of a Broad-spectrum Resistance Gene, Pi40 Improved Blast Resistance of Two Elite Rice (Oryza sativa L.) Cultivars of Turkey, Molecular Plant Breeding, 7(33): 1-15 (doi: 10.5376/mpb.2016.07.0033) 

Rice blast, caused by Magnaporthe oryzae is the most serious fungal disease of cultivated rice (Oryza sativa). In serious disease infection, significant yield loss in japonica and indica rice occurs every year worldwide. Of the 100 blast resistance genes identified, majorities are race specific and resistance breaks down rapidly. However, the new resistance gene, Pi40 shows broad-spectrum resistance to blast races in many tropical and temperate rice growing countries including Turkey. In this study, the Pi40 gene was introgressed into two Turkish elite cultivars, Osmancik-97 and Halilbey, to improve with broad-spectrum durable blast resistance and high yield potential through marker-assisted backcross breeding. Advanced backcross lines (ABLs) of BC₃F₆ and BC₄F₆ generations were produced from the crosses of Osmancik-97 and Halilbey with the Pi40-donor line, IR83260-1-1-1-5-B-3-1-2-B. ABLs with homozygous Pi40 alleles were selected by foreground analysis using gene-specific CAPS DNA marker 9871.T7E2b. The two varieties were expressing high susceptibility to blast disease isolates in Turkey and Philippines. Eleven selected ABLs expressed strong resistance to blast races in natural field and spray inoculation conditions. Background analysis of selected ABLs with 6K SNP assays showed 90.07% and 70.78% recovery of the recurrent genotype for Osmancik-97 and Halilbey ABLs respectively. We have produced valuable resources for blast disease resistance and developed improved breeding lines with strong resistance to blast for their cultivation in Turkey. Our new strategy of transferring the novel blast resistance gene (Pi40) into Turkish varieties will enhance rice production and productivity in the temperate regions of the world.

Blast; Marker-assisted backcrossing; Pi40; Resistance, Rice