Expression patterns of defense genes in resistance of the panicles exserted from the caulis and from the tillers to neck blast in rice

The rice variety Xiushui227 is resistant to neck blast in the panicles exserted from the caulis but susceptible in the panicles from the tillers, however, the other variety Xiushui09 is susceptible to neck blast in the panicles from the caulis but resistant in the panicles from the tillers. These two varieties were used to analyze the expression patterns of defense genes in the panicles from the caulis and the first first-class tiller at the preliminary heading stage, after inoculating the necks in vitro with Magnaporthe oryzae, respectively. All defense genes (pathogenesis-related genes PR1a, Gns1 (1,3; 1,4-β-glucanase), Cht-1 (chitinase), PR4, PR5, and PR10a, secondary metabolite pathway genes PAL (phenylalanine ammonia-lyase), CHS (chalcone synthase), and LOX (lipoxygenase), and oxidative stress-related protein genes POX22.3 (peroxidase), and PPO (polyphenol oxidase)) used in this experiment except Cht-1 and PR5 could participate in defending Xiushui227 against neck blast in the panicles from the caulis. All defense genes used in this study except Cht-1, PR10a, and PPO may play roles in defending Xiushui09 against neck blast in the panicles from the tillers.