Bezemer T M, Wagenaar I R, van Dam N M, van der Putten W H, Wäckers F L
Netherlands Institute of Ecology (NIOO-KNAW), Centre for Terrestrial Ecology, PO Box 40, 6666 ZG Heteren, The Netherlands.
J Chem Ecol. 2004 Jan;30(1):53-67. doi: 10.1023/b:joec.0000013182.50662.2a.
Studies on induced defenses have predominantly focused on foliar induction by above-ground herbivores and pathogens. However, roots are attacked by as many if not more phytophages than shoots, so in reality plants are exposed to above- and below-ground attack. Here, we report effects of foliar and/or root damage on terpenoid aldehyde accumulation in cotton (Gossypium herbaceum). Using HPLC, we analyzed concentrations of individual terpenoid aldehydes in foliage and root tissue. In undamaged plants, terpenoid aldehydes were concentrated in young immature main leaves. Concentrations in side leaves, branching from the main leaves, did not differ among leaf position. Above-ground feeding by Spodopterta exigua larvae on a mature leaf enhanced terpenoid concentrations in immature leaves but not in the damaged leaf. In particular, concentrations of hemigossypolone and the heliocides 1 and 4 were enhanced following herbivory. Root herbivory by wireworms (Agriotes lineatus) also resulted in an increase in terpenoid levels in the foliage. In contrast with foliar herbivory, both immature and mature leaves were induced. However, the level of induction after root herbivory was much lower compared to foliar herbivory. Plants exposed to root herbivory also had significantly higher levels of terpenoid aldehydes in root tissue, while no such effect was found following foliar herbivory. Plants exposed to both root and foliar herbivory appeared to induce primarily above-ground at the cost of below-ground defense. The implications for above- and below-ground Mutitrophic interactions are discussed.
关于诱导防御的研究主要集中在地上食草动物和病原体对叶片的诱导作用上。然而，根部受到的植食性动物攻击即使不比地上部分少，也与之相当，所以实际上植物会受到地上和地下的双重攻击。在此，我们报告了叶片和/或根部损伤对棉花（草棉）中萜类醛积累的影响。我们使用高效液相色谱法分析了叶片和根组织中各个萜类醛的浓度。在未受损的植株中，萜类醛集中在幼嫩的主叶中。从主叶分支出来的侧叶中的浓度在不同叶位之间没有差异。棉铃虫幼虫在成熟叶片上进行地上取食会提高未成熟叶片中的萜类浓度，但受损叶片中则不会。特别是，食草后半棉酚和半日花素1及4的浓度会升高。金针虫（黑线叩头虫）对根部的取食也会导致叶片中萜类水平的增加。与叶片取食不同，未成熟和成熟叶片都会被诱导。然而，根部取食后的诱导水平与叶片取食相比要低得多。遭受根部取食的植株根部组织中的萜类醛水平也显著更高，而叶片取食后则未发现这种效应。同时遭受根部和叶片取食的植株似乎主要诱导地上部分，而以地下防御为代价。本文讨论了其对地上和地下多营养级相互作用的影响。
