Have you ever seen the rain? The life cycle of Crotalaria retusa (Fabaceae) reveals reproductive resilience under drought conditions.

Abstract

Anthropogenic climate change is altering precipitation patterns, increasing the length of the dry season and rainfall variability. In this context, the present study aimed to evaluate the influence of drought on the life cycle and reproductive success of the invasive Crotalaria retusa L. (Fabaceae). For this, the seeds were sown in plastic pots containing 3 kg of soil from the collection area. The experiment consisted of 10 treatments with field capacity ranging from 10 to 100%. Germination traits were assessed until seedling emergence and morphological and reproductive parameters were analyzed every 10 days until the end of the reproductive phase, totaling 190 days. Reduced water availability significantly affected plant growth, reducing stem length size, stem diameter and number of leaves at the lowest field capacities evaluated. The reproductive phase was also affected by the low availability of water in the soil. Flowering had a reduction in the number of flower buds and flowers with a reduction in water content. The size and width of the fruits under 50% and 40% field capacity were smaller than in the other treatments. C. retusa is tolerant of low soil water content and can establish itself in field capacities below 30%, but has not produced flowers, fruits, and seeds. The population of the species studied shows a reduction in its growth appears to be resist severe drought and remain in the environment. This may enhance the invasive potential of the species in semi-arid environments.