Regulation of fruit and seed set in Anagyris foetida L. (Fabaceae): The role of intrinsic factors

Abstract

We investigated the role of resource limitation, ovary reserve, and selective abortion in controlling flower and fruit set in the Mediterranean leguminous shrub Anagyris foetida. The removal of bracts, but not that of leaves, reduced the initiation of fruit with respect to controls. The removal of a large proportion (2/3 of the total) of preanthesic inflorescences increased the reproductive capacity of individuals via two different strategies: (1) maintaining the number of fruit-bearing inflorescences, but increasing the number of fruits per inflorescence and seeds per fruit; and (2) increasing the number of fruit-bearing inflorescences, while maintaining fruits/inflorescence and seeds/fruit ratios unchanged. At the level of the inflorescence, most of the ripe fruits were located on the basalmost whorls of the raceme. Within the legume, fertilization was independent of the position of ovules, although the more basal presented lower rates of fertilization than the more central-stylar. The same was observed for the probability of a fertilized ovule to develop into a mature seed.

Keywords:

• Fruit-set
• inflorescences
• Leguminosae
• Anagyris foetida
• resource limitation
• seed abortion
• seed set

Acknowledgements

This work was financed by the Ministry of Education and Science of Spain through projects BOS2002-00703 and CGL2005-00783/BOS, both co-financed by ERDF. A predoctoral grant of the same Ministry to FJV (BES-2003-2187) is greatly appreciated. We thank Dr Miguel González for statistical assistance and one anonymous referee for the constructive critique provided.