Cárdenas Rafael E, Rodríguez-Ortega Camila, Utreras Daniel, Forrister Dale L, Endara María-José, Queenborough Simon A, Alvia Pablo, Menéndez-Guerrero Pablo A, Báez Selene, Donoso David A
Museo de Zoología QCAZ, Laboratorio de Entomología y Herbario QCA, Laboratorio de Ecología de Plantas, Escuela de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Av. 12 de Octubre 1076 y Roca, Apdo. 17-01-2184, Quito, Ecuador.
Smithsonian Tropical Research Institute, Apdo. 0843-03092, Balboa, Republic of Panama.
Sci Rep. 2024 Aug 1;14(1):17813. doi: 10.1038/s41598-024-67140-4.
Over 125 million years of ant-plant interactions have culminated in one of the most intriguing evolutionary outcomes in life history. The myrmecophyte Duroia hirsuta (Rubiaceae) is known for its mutualistic association with the ant Myrmelachista schumanni and several other species, mainly Azteca, in the north-western Amazon. While both ants provide indirect defences to plants, only M. schumanni nests in plant domatia and has the unique behaviour of clearing the surroundings of its host tree from heterospecific plants, potentially increasing resource availability to its host. Using a 12-year survey, we asked how the continuous presence of either only M. schumanni or only Azteca spp. benefits the growth and defence traits of host trees. We found that the continuous presence of M. schumanni improved relative growth rates and leaf shearing resistance of Duroia better than trees with Azteca. However, leaf herbivory, dry matter content, trichome density, and secondary metabolite production were the same in all trees. Survival depended directly on ant association (> 94% of trees died when ants were absent). This study extends our understanding of the long-term effects of strict ant-plant mutualism on host plant traits in the field and reinforces the use of D. hirsuta-M. schumanni as a model system suitable for eco-co-evolutionary research on plant-animal interactions.
超过1.25亿年的蚂蚁与植物的相互作用，最终形成了生命史上最引人入胜的进化结果之一。蚁栖植物多毛杜若（茜草科）以其与蚂蚁舒氏密蚁以及其他几种物种（主要是阿兹特克蚁）在亚马逊西北部的互利共生关系而闻名。虽然这两种蚂蚁都为植物提供间接防御，但只有舒氏密蚁在植物叶窝中筑巢，并且具有从宿主树周围清除异种植物的独特行为，这可能会增加宿主可利用的资源。通过一项为期12年的调查，我们探究了仅舒氏密蚁或仅阿兹特克蚁的持续存在如何影响宿主树的生长和防御特性。我们发现，与有阿兹特克蚁的树相比，舒氏密蚁的持续存在能更好地提高多毛杜若的相对生长速率和叶片抗剪切性。然而，所有树的叶片食草率、干物质含量、毛状体密度和次生代谢产物产量是相同的。存活率直接取决于与蚂蚁的共生关系（当没有蚂蚁时，超过94%的树死亡）。这项研究扩展了我们对严格的蚂蚁与植物互利共生对野外宿主植物特性的长期影响的理解，并强化了将多毛杜若 - 舒氏密蚁作为适合植物 - 动物相互作用生态协同进化研究的模型系统的应用。
