Di Giusto B. auteur aut IRD Dounias Edmond auteur aut IRD McKey D. B. auteur aut IRD text journalArticle eng text/pdf reformatted digital access Plants with simple architecture and strong constraints on their growth may offer critical insights into how growth strategies affect the tolerance of plants to herbivory. Although Dioscorea praehensilis, a wild yam of African forests, is perennial, both aerial apparatus and tuber are annually renewed. Each year, the tuber produces a single stem that climbs from the ground to the forest canopy. This stem bears no leaves and no branches until it reaches optimal light conditions. Once in the canopy, the plant's production fuels the filling of a new tuber before the plant dies back to the ground. We hypothesized that if deprived of ant defense, the leafless growth phase is a vulnerable part of the cycle, during which a small amount of herbivory entails a high cost in terms of loss of opportunity. We compared the growth of stems bearing ants or not as well as of intact stems and stems subjected to simulated or natural herbivory. Ants reduce herbivory; herbivory delays arrival to the canopy and shortens the season of production. Artificially prolonging the stem growth to the canopy increased plant mortality in the following year and, in surviving plants, reduced the stem diameter and likely the underground reserves produced. Tuber size is a key variable in plant performance as it affects both the size of the aerial apparatus and the duration of its single season of production. Aerial apparatus and tuber are thus locked into a cycle of reciprocal annual renewal. Costs due to loss of opportunity may play a major role in plant tolerance to herbivory, especially when architectural constraints interact with ecological conditions to shape the plant's growth strategy. specialized monocotyledon perennial plant architecture plant/herbivore interactions resource storage AFRIQUE DE L'OUEST AFRIQUE CENTRALE CAMEROUN 076 082 7 16 6493-6506 2017 2045-7758 https://www.documentation.ird.fr/hor/fdi:010070996 10.1002/ece3.3066 2045-7758 [F B010070996] https://www.documentation.ird.fr/hor/fdi:010070996 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers17-09/010070996.pdf IRD - Base Horizon / Pleins textes 2017-10-03 2023-07-11 fdi:010070996 fre