Department of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, the Chinese Academy of Sciences, Kunming 650201, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
J Integr Plant Biol. 2018 May;60(5):412-431. doi: 10.1111/jipb.12633. Epub 2018 Mar 14.
Atmospheric CO levels are rapidly increasing due to human activities. However, the effects of elevated CO (ECO ) on plant defense against insects and the underlying mechanisms remain poorly understood. Here we show that ECO increased the photosynthetic rates and the biomass of tobacco and rice plants, and the chewing lepidopteran insects Spodoptera litura and Mythimna separata gained less and more mass on tobacco and rice plants, respectively. Consistently, under ECO , the levels of jasmonic acid (JA), the main phytohormone controlling plant defense against these lepidopteran insects, as well as the main defense-related metabolites, were increased and decreased in insect-damaged tobacco and rice plants. Importantly, bioassays and quantification of defense-related metabolites in tobacco and rice silenced in JA biosynthesis and perception indicate that ECO changes plant resistance mainly by affecting the JA pathway. We further demonstrate that the defensive metabolites, but not total N or protein, are the main factors contributing to the altered defense levels under ECO . This study illustrates that ECO changes the interplay between plants and insects, and we propose that crops should be studied for their resistance to the major pests under ECO to predict the impact of ECO on future agroecosystems.
由于人类活动，大气中二氧化碳水平正在迅速上升。然而，升高的二氧化碳（ECO）对植物防御昆虫的影响及其潜在机制仍知之甚少。在这里，我们表明 ECO 增加了烟草和水稻植株的光合速率和生物量，咀嚼鳞翅目昆虫斜纹夜蛾和粘虫在烟草和水稻植株上的体重分别增加和减少。一致地，在 ECO 下，茉莉酸（JA）的水平，控制植物对这些鳞翅目昆虫防御的主要植物激素，以及主要的防御相关代谢物，在受昆虫损伤的烟草和水稻植株中增加和减少。重要的是，在 JA 生物合成和感知中沉默的烟草和水稻的生物测定和防御相关代谢物的定量表明，ECO 主要通过影响 JA 途径来改变植物的抗性。我们进一步证明，防御性代谢物，而不是总氮或蛋白质，是 ECO 下改变防御水平的主要因素。本研究表明，ECO 改变了植物和昆虫之间的相互作用，我们建议应研究作物对 ECO 下主要害虫的抗性，以预测 ECO 对未来农业生态系统的影响。
