Premium
INTER‐ AND INTRAGENOTYPIC COMPETITION UNDER ELEVATED CARBON DIOXIDE IN ARABIDOPSIS THALIANA
Author(s) -
Andalo Christophe,
Goldringer Isabelle,
Godelle Bernard
Publication year - 2001
Publication title -
ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.144
H-Index - 294
eISSN - 1939-9170
pISSN - 0012-9658
DOI - 10.1890/0012-9658(2001)082[0157:iaicue]2.0.co;2
Subject(s) - competition (biology) , arabidopsis thaliana , biology , biological dispersal , genotype , natural selection , carbon dioxide , selection (genetic algorithm) , botany , ecology , population , horticulture , gene , genetics , demography , artificial intelligence , sociology , computer science , mutant
The consequences of elevated CO 2 on plant growth have been well studied on individual plants. The response of a more complex system with several plants interacting is less understood—a situation that limits our capacity to predict the response of natural plant communities. In this study we analyzed the effect of CO 2 enrichment on intergenotypic competition in Arabidopsis thaliana. Seeds of five genotypes collected from different natural populations were used. Each genotype was cultivated in a pure stand and in a mixture with each of the other four genotypes in two CO 2 conditions (ambient and elevated). At harvest time, genotype fitness was estimated by the number of fruits and seeds produced per plant. At current levels of CO 2 , genotypes performed better in a pure stand than in a mixture. Kin selection, associated with the low seed dispersal and autogamous reproductive regime of A. thaliana, is invoked to explain these positive responses among plants of similar genotype. Surprisingly, in a high‐CO 2 atmosphere (700 μL/L) the reverse situation was observed: plants performed better in mixtures than in pure stands. Positive frequency‐dependent selection under ambient CO 2 concentration became negative under elevated CO 2 , which could lead more easily to the maintenance of genetic variation. This hypothesis was tested with a simple model of competition. At equilibrium, the simulation did not show coexistence among more genotypes under elevated CO 2 than under ambient CO 2 concentration. However, this study allows predictions about evolutionary trajectories under high‐CO 2 conditions. In A. thaliana, genotypes that will maintain the most their ability to grow well in pure stand should be selected under increasing CO 2 .