Cotyledon damage at the seedling stage affects growth and flowering potential in mature plants

Seedling herbivory is an important selective filter influencing patterns of plant community composition. Nevertheless, while many of the mechanisms governing seedling selection by herbivores are well established, the effects of tissue loss at the seedling stage on subsequent plant development are poorly understood. Here we examined how the removal of 50 or approximately 100% of cotyledon area from 7-d-old chalk grassland seedlings affected subsequent plant growth and flowering over a 100-d period. Cotyledon damage had a significant effect on growth during the establishment phase for six of the nine species. For two species, significant effects on plant growth were manifest in 100-d-old plants. Of the five species that flowered, three developed fewer inflorescences or flowered later as a consequence of cotyledon damage suffered as a seedling. Our results show that, in addition to the direct effect of herbivory on seedling mortality, more subtle sublethal effects may also influence plant establishment. Reduced growth as a result of cotyledon damage may have implications for plant competition during the establishment phase, and on subsequent reproductive success at maturity.