Fig. 5

Quantitative RT-PCR analysis of genes in the ethylene pathway. a Relative transcript levels of the ET-response genes OsERF1, OsERF70 and OsEBP89. b Relative transcript levels of the ET-signaling gene OsEIN2. c Relative transcript levels of the ET-biosynthesis genes OsACS1 and OsACO7. Gene expression levels were analyzed at 6, 24 and 72 h post-inoculation and normalized with three internal reference genes, OsEXP, OsEif5C and OsEXPnarsai. Data are shown as relative transcript levels in comparison with the control roots (expression level set at 1). The bars represent the mean expression levels±SE from two independent biological replicates and three technical replicates, each containing a pool of 6 plants. Asterisks indicate significant differential expression (Duncan’s multiple range test with P ≤ 0.05). d Ethylene concentration in rice plants. The ethylene insensitive3-like1 gene, OsEIL1–2-RNAi line deficient in ET signaling and the transgenic line overexpressing OsEIL1-OX amended with or without silicon were transplanted in a sealed plexiglass bottle and inoculated with 100 J2 s each. Samples of air in each plexiglass box were analyzed with a gas chromatograph at 24 hpi. e Effect of silicon amendment on nematode infection in ethylene mutants. The ethylene insensitive3-like1gene, OsEIL1–2-RNAi line deficient in ET signaling and the transgenic line overexpressing OsEIL1-OX amended with or without silicon were inoculated with 100 J2 s each, and nematodes in rice roots were investigated at 14 dpi. A japonica wild type (WD), Taijing394, was used as a control. The bars represent the means of the data from two similar experiments, each containing 10 individual plants. Different letters indicate significant differences (Duncan’s multiple range test with P ≤ 0.05)