Botany, Ahead of Print.
It is well known that ethylene affects plants; however, its regulatory role in plant-derived methane (CH4) has not been addressed. In this study, we determined the effects of exogenous ethylene on canola (Brassica napus L.) growth and physiological traits, endogenous ethylene, and aerobic methane emission. Plants were grown under experimental conditions (22/18 °C, 16 h light : 8 dark; 500 µmol photons·m−2·s−1) for 21 d and were exposed to exogenous ethylene for different durations (0, 1, or 2 h·d−1). Methane and ethylene emissions were measured after 7, 14, and 21 d, whereas growth and physiological traits were measured after 21 d. Overall, methane emissions decreased, but endogenous ethylene increased over time with exogenous ethylene. Plants treated with exogenous ethylene had decreased growth, biomass, gas exchange, chlorophyll fluorescence, photosynthetic pigments, and nitrogen balance index, but increased flavonoids. Both methane and ethylene were negatively correlated with most growth and physiological traits. In conclusion, this study revealed that exogenous ethylene significantly increased both endogenous ethylene and methane emissions. Plants exposed to exogenous ethylene were likely stressed and emitted methane, which increased with exposure time.

中文翻译：

---

外源乙烯通过对植物生长和生理过程产生不利影响来增加油菜籽的甲烷排放

植物学，超前印刷。
众所周知，乙烯会影响植物；然而，其在植物源甲烷 (CH4) 中的调节作用尚未得到解决。在这项研究中，我们确定了外源乙烯对油菜 (Brassica napus L.) 生长和生理特性、内源乙烯和有氧甲烷排放的影响。植物在实验条件（22/18 °C，16 小时光照：8 暗；500 µmol 光子·m-2·s-1）下生长 21 天，并暴露于外源乙烯不同的持续时间（0、1 或2 h·d-1)。在 7、14 和 21 天后测量甲烷和乙烯排放量，而在 21 天后测量生长和生理特征。总体而言，甲烷排放量下降，但内源性乙烯随着外源性乙烯的增加而增加。用外源乙烯处理的植物生长、生物量、气体交换、叶绿素荧光、光合色素和氮平衡指数，但增加黄酮类化合物。甲烷和乙烯都与大多数生长和生理特征呈负相关。总之，这项研究表明，外源乙烯显着增加了内源乙烯和甲烷排放。暴露于外源乙烯的植物可能会受到压力并排放甲烷，随着暴露时间的增加而增加。