Residual effects of the Xa-4 resistance gene in three rice cultivars when exposed to a virulent isolate of Xanthomonas campestris pv. oryzae |
| |
| Authors: | M Koch J E Parlevliet |
| |
| Institution: | (1) Plant Breeding Department, Agricultural University, P.O. Box 386, Wageningen, The Netherlands;(2) International Rice Research Institute, P.O. Box 933, Manila, Philippines;(3) Present address: Institute of Field and Garden Crops, The Volcani Center, P.O. Box 6, Bet Dagan, Israel |
| |
| Abstract: | Summary F2 plants of five, and F3 plants of three, crosses between genotypes carrying the race-specific resistance gene Xa-4 and genotypes not carrying this gene were inoculated with two isolates of Xanthomonas campestris pv. oryzae. Half the tillers of each plant received isolate PX061, avirulent on the Xa-4 gene, the other half of the tillers received isolate PX099, virulent for the Xa-4 gene. The F2 and F3 populations segregated for a single dominant resistance gene, Xa-4.The parental, F2 and F3 genotypes not carrying Xa-4 had mean lesion lengths between 28 and 29 cm for both isolates. The Xa-4 carrying parents showed a mean lesion length of 2.7 cm with the avirulent isolate and of 12.4 cm with the virulent isolate. The Xa-4 carrying F2 and F3 genotypes had mean lesion lengths of 5.2 and 20.1 cm for the two isolates, respectively. These observations strongly indicate that the Xa-4 gene, carried by the rice genotypes studied (IR28, Cisadane and BR51-282-8), had a considerable residual effect when exposed to virulent isolate PXO99. |
| |
| Keywords: | Oryza sativa rice Xanthomonas campestris pv oryzae bacterial blight ghost gene quantitative resistance residual resistance |
| 本文献已被 SpringerLink 等数据库收录！ |
|
