In plants, F₁ hybrids showing hybrid weakness exhibit weaker growth than their parents. The phenotypes of hybrid weakness are often suppressed at certain temperatures. However, it is unclear whether hybrid weakness in Capsicum annuum × C. chinense is temperature-dependent or not. Our study showed that Capsicum hybrid weakness was suppressed at 30 and 35 °C and was induced at 15, 20, and 25 °C. Moreover, we investigated the time course of hybrid weakness in cell death, metabolite content, and gene expression in leaves of plants transferred to 20 °C after growing at 30 °C for 21 days. The expression of pathogen defense-related genes was upregulated at 1 day after transfer to 20 °C (DAT). Cell death was detected at 7 DAT, plant growth had almost stopped since 14 DAT, and sugars were accumulated at 42 DAT in hybrid plants. The study revealed that some sugar transporter genes, which had been upregulated since 7 DAT, were involved in sugar accumulation in Capsicum hybrid weakness. Thus, our results demonstrated that gene expression changes occur first, followed by physiological and morphological changes after induction of hybrid weakness. These responses observed in this study in Capsicum hybrid weakness are likely to be owed to plant defense responses-like reactions.

在植物中，表现出杂种弱点的F ₁杂种表现出比它们的亲本弱的生长。杂种弱点的表型通常在某些温度下被抑制。然而，尚不清楚Capsicum annuum × C. chinense 的杂交弱点是否与温度有关。我们的研究表明，辣椒混合弱点在 30 和 35°C 时被抑制，并在 15、20 和 25°C 时被诱导。此外，我们研究了在 30°C 下生长 21 天后转移到 20°C 的植物叶片中细胞死亡、代谢物含量和基因表达方面的杂交弱点的时间过程。病原体防御相关基因的表达在转移至 20 °C (DAT) 后 1 天上调。在第 7 天检测到细胞死亡，从第 14 天开始植物生长几乎停止，并且在杂交植物中的糖在第 42 天积累。研究表明，一些自 7 DAT 开始上调的糖转运蛋白基因参与了辣椒的糖分积累。混合弱点。因此，我们的结果表明，基因表达变化首先发生，然后是诱导杂交弱点后的生理和形态变化。在这项研究中观察到的辣椒杂种弱点的这些反应可能是由于植物防御反应样反应。