| Autor: |
Biswas PL; National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Graduate School of Chinese Academy of Agricultural Sciences (GSCAAS), Haidian District, Beijing 100081, China.; Bangladesh Rice Research Institute (BRRI), Joydevpur, Gazipur 1701, Bangladesh., Nath UK; Department of Genetics and Plant Breeding, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh., Ghosal S; Bangladesh Rice Research Institute (BRRI), Joydevpur, Gazipur 1701, Bangladesh., Goswami G; Department of Genetics and Plant Breeding, Patuakhali Science and Technology University, Patuakhali 8600, Bangladesh., Uddin MS; Bangladesh Agricultural Research Institute, Gazipur 1701, Bangladesh., Ali OM; Department of Chemistry, Turabah University College, Turabah Branch, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia., Latef AAHA; Botany and Microbiology Department, Faculty of Science, South Valley University, Qena 83523, Egypt., Laing AM; CSIRO Agriculture & Food, St. Lucia, QLD 4067, Australia., Gao YM; National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Graduate School of Chinese Academy of Agricultural Sciences (GSCAAS), Haidian District, Beijing 100081, China., Hossain A; Department of Agronomy, Bangladesh Wheat and Maize Research Institute, Dinajpur 5200, Bangladesh. |
| Abstrakt: |
Bacterial blight (BB) is caused by Xanthomonas oryzae pv. oryzae and is one of the most important diseases in rice. It results in significantly reduced productivity throughout all rice-growing regions of the world. Four BB resistance genes have been reported; however, introgression of a single gene into rice has not been able to sufficiently protect rice against BB infection. Pyramiding of effective BB resistance genes (i.e., Xa genes) into background varieties is a potential approach to controlling BB infection. In this study, combinations of four BB resistance genes, Xa4 , xa5 , xa13 , and Xa21 , were pyramided into populations. The populations were derived from crossing Ciherang (a widespread Indonesian rice variety) with IRBB60 (resistance to BB). Promising recombinants from the F 6 generation were identified by scoring the phenotype against three virulent bacterial strains, C5, P6, and V, which cause widespread BB infection in most rice-growing countries. Pyramiding of genes for BB resistance in 265 recombinant introgressed lines (RILs) were confirmed through marker-assisted selection (MAS) of the F 5 and F 6 generations using gene-specific primers. Of these 265 RILs, 11, 34 and 45 lines had four, three, or two BB resistance genes, respectively. The RILs had pyramiding of two or three resistance genes, with the Xa4 resistance gene showing broad spectrum resistance against Xoo races with higher agronomic performance compared to their donor and recipients parents. The developed BB-resistant RILs have high yield potential to be further developed for cultivation or as sources of BB resistance donor material for varietal improvement in other rice lines. |
