Ongoing human-induced changes in the composition of the atmosphere continue to stimulate interest in the effects of high CO₂ on plants, but its potential impact on inducible plant defense pathways remains poorly defined. Recently, several studies have reported that growth at elevated CO₂ is sufficient to induce defenses such as the salicylic acid pathway, thereby increasing plant resistance to pathogens. These reports contrast with evidence that defense pathways can be promoted by photorespiration, which is inhibited at high CO₂. Here, we review signaling, metabolic, and redox processes modulated by CO₂ levels and discuss issues to be resolved in elucidating the relationships between primary metabolism, inducible defense, and biotic stress resistance.

持续不断的由人为引起的大气成分变化继续激发人们对高CO ₂对植物的影响的兴趣，但其对诱导植物防御途径的潜在影响仍然不清楚。近来，一些研究报道了在升高的CO _2下的生长足以诱导防御作用，例如水杨酸途径，从而增加植物对病原体的抗性。这些报道与证据表明光呼吸可以促进防御途径，而高CO ₂抑制了光呼吸作用。在这里，我们回顾由CO ₂调节的信号传导，代谢和氧化还原过程 水平并讨论阐明初级代谢，诱导防御和生物逆境抗性之间的关系所要解决的问题。