Xiao Li, Carrillo Juli, Siemann Evan, Ding Jianqing
Key Laboratory of Aquatic Plant and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China.
University of Chinese Academy of Sciences, Beijing, China.
AoB Plants. 2019 Feb 1;11(1):plz003. doi: 10.1093/aobpla/plz003. eCollection 2019 Feb.
Herbivory can induce both general and specific responses in plants that modify direct and indirect defence against subsequent herbivory. The type of induction (local versus systemic induction, single versus multiple defence induction) likely depends both on herbivore identity and relationships among different responses. We examined the effects of two above-ground chewing herbivores (caterpillar, weevil) and one sucking herbivore (aphid) on indirect defence responses in leaves and direct defence responses in both leaves and roots of tallow tree, We also included foliar applications of methyl jasmonate (MeJA) and salicylic acid (SA). We found that chewing herbivores and MeJA increased above-ground defence chemicals but SA only increased below-ground total flavonoids. Herbivory or MeJA increased above-ground indirect defence response (extrafloral nectar) but SA decreased it. Principal component analysis showed there was a trade-off between increasing total root phenolics and tannins (MeJA, chewing) versus latex and total root flavonoids (aphid, SA). For individual flavonoids, there was evidence for systemic induction (quercetin), trade-offs between compounds (quercetin versus kaempferitrin) and trade-offs between above-ground versus below-ground production (isoquercetin). Our results suggest that direct and indirect defence responses in leaves and roots depend on herbivore host range and specificity along with feeding mode. We detected relationships among some defence response types, while others were independent. Including multiple types of insects to examine defence inductions in leaves and roots may better elucidate the complexity and specificity of defence responses of plants.
食草作用可诱导植物产生一般和特定的反应，从而改变对后续食草行为的直接和间接防御。诱导类型（局部诱导与系统诱导、单一防御诱导与多重防御诱导）可能既取决于食草动物的种类，也取决于不同反应之间的关系。我们研究了两种地上咀嚼式食草动物（毛虫、象鼻虫）和一种吸食式食草动物（蚜虫）对乌桕叶间接防御反应以及叶和根直接防御反应的影响。我们还进行了茉莉酸甲酯（MeJA）和水杨酸（SA）的叶面喷施。我们发现，咀嚼式食草动物和MeJA增加了地上防御化学物质，但SA仅增加了地下总黄酮含量。食草作用或MeJA增加了地上间接防御反应（花外蜜），但SA降低了该反应。主成分分析表明，在增加总根酚类和单宁（MeJA、咀嚼式）与增加乳胶和总根黄酮（蚜虫、SA）之间存在权衡。对于个别黄酮类化合物，有系统诱导的证据（槲皮素）、化合物之间的权衡（槲皮素与山奈酚苷）以及地上与地下产量之间的权衡（异槲皮苷）。我们的结果表明，叶和根中的直接和间接防御反应取决于食草动物的宿主范围和特异性以及取食方式。我们检测到了一些防御反应类型之间的关系，而其他一些则是独立的。纳入多种昆虫来研究叶和根中的防御诱导可能更好地阐明植物防御反应的复杂性和特异性。
