Fig. 1. CaKAN3 silencing significantly increased the susceptibility of pepper plants to R. solanacearum inoculation (RSI) under HTHH.

a The success of CaKAN3 silencing by virus-induced gene silencing (VIGS) by measuring the transcript levels of CaKAN3 in RTHH-, RSRT-, HTHH- and RSHT-challenged TRV:CaKAN3 pepper plants at 24 hours post-treatment (hpt). The transcript levels of TRV:00/RTHH were set to 1. b Effect of CaKAN3 silencing on the response of pepper plants to RSRT and RSHT treatment at 3 and 12 dpt, respectively. c The disease index of CaKAN3-silenced pepper plants challenged with RSRT or RSHT from 0 to 12 dpt. A total of 24 plants were dynamically scored for each species. In b, c, the experiment was carried out three times with similar results. d Growth of R. solanacearum in R. solanacearum-inoculated CaKAN3-silenced plants at room temperature or under HTHH, shown as colony-forming units (cfu). Data are shown as the means ± standard errors of eight replicates. Asterisks above the bars indicate significant differences between means (P < 0.01), as calculated with a t test. The center line represents the median value and the boundaries indicate the 25th percentile (upper) and the 75th percentile (lower). Whiskers extend to the largest and smallest value. e Decreased flg22-induced H₂O₂ production in CaKAN3-silenced pepper plants at HTHH. The results shown are representative of two independent experiments. Data are shown as the means ± standard errors of six replicates. f, Relative transcript levels of CaMgst3 and CaPRP1 in TRV:00 and TRV:CaKAN3 pepper plants challenged with RTHH, RSRT, HTHH or RSHT. The transcript levels of TRV:00/RTHH were set to 1. In a and f, data represent the mean ± SD of four replicates. CaActin was used as an internal control, and asterisks above the bars indicate significant differences between means (P < 0.01), as calculated with Fisher’s protected t test. All replicates were from different plants. In a–f, source data are provided as a Source Data file.