College of Life Science and Technology, Xinjiang University, Urumqi, 830046, China.
Institute of Agro-products Processing Science and Technolog, Xinjiang Academy of Agricultural and Reclamation Science, Shihezi, 832000, China.
Sci Rep. 2020 Mar 4;10(1):4060. doi: 10.1038/s41598-020-60749-1.
The massive use of fossil fuels since the industrial revolution has led to a rapid increase in the concentration of carbon dioxide (CO) in the atmosphere. What effects elevated CO concentrations (ECO) have on the defense mechanisms plants employ against insects remains poorly understood. This study showed that ECO of 750 ± 20 mmol/mol, increased the photosynthetic rate and biomass gain of tobacco and melon plants. However, while mass gain of Spodoptera litura, a nocturnal moth in the Noctuidae family, was higher when feeding on tobacco plants under ECO, mass gain of Diaphania indica was reduced when feeding on melon plant at ECO compared to ambient CO2. Plants have many mechanisms to defend themselves against insects. Jasmonic acid (JA) is a crucial element of plant defense against lepidopteran insects. Our study showed that JA levels increased in tobacco plants under ECO but decreased in melon plants. It is speculated that ECO changes plant resistance to insects mainly by affecting the JA signaling pathway. Nutrient analysis suggested defensive metabolites rather than changes in the total nitrogen or protein content of the plants led to the changes in plant defense levels under ECO. In summary, ECO affects the interaction between plants and insects. The results may provide a theoretical basis for studying the changes in crop resistance to pests under ECO and predicting the impact of ECO on future agro-ecosystems.
自工业革命以来，化石燃料的大量使用导致大气中二氧化碳（CO）浓度迅速增加。升高的 CO 浓度（ECO）对植物防御昆虫的机制有什么影响，目前仍知之甚少。本研究表明，750±20mmol/mol 的 ECO 增加了烟草和瓜类植物的光合速率和生物量积累。然而，当夜间蛾类烟草夜蛾在 ECO 下以烟草为食时，其质量增加，但当在 ECO 下以瓜类植物为食时，印度谷螟的质量增加则减少。植物有许多机制来防御昆虫。茉莉酸（JA）是植物防御鳞翅目昆虫的关键元素。我们的研究表明，ECO 下烟草植物中的 JA 水平升高，但在 ECO 下瓜类植物中的 JA 水平降低。据推测，ECO 主要通过影响 JA 信号通路来改变植物对昆虫的抗性。营养分析表明，是防御性代谢物而不是植物总氮或蛋白质含量的变化导致了 ECO 下植物防御水平的变化。总之，ECO 影响了植物与昆虫之间的相互作用。这些结果可能为研究 ECO 下作物对害虫抗性的变化以及预测 ECO 对未来农业生态系统的影响提供理论依据。
