Trade-offs between reproductive allocation and storage in species of Oenothera L. (Onagraceae) native to Argentina

A trade-off between reproduction and survival arises because current reproduction diminishes levels of a limiting resource such that less can be placed in storage organs for the survival of an organism during the unfavorable season. Oenothera is a particularly suited genus for studying those kind of trade-offs because it contains species with different life-history strategies (annual, biennial and perennial). Since allocation to leaves is a major factor associated with changes in life-history, here we tested the hypothesis that Oenothera leaf attributes would affect plant reproductive effort and therefore, root reserves. We selected two groups of taxa differing in their leaf area ratio (low- and high-LAR) and we compared their pattern of resource allocation to growth, reproduction and storage. Path analysis confirmed our hypothesis that LAR is the most important variable in explaining variation in allocation to reproduction or storage. The group with high allocation to leaves assigned resources preferentially to storage while the other group allocated more resources to reproduction, as predicted. A trade-off between reproduction and storage was only confirmed for the high-LAR group. The low-LAR group showed the life-history tactic of annual plants, while the high-LAR group exhibited a strategy generally associated with perenniality. (c) 2007 Elsevier Masson SAS. All rights reserved.