Potentiality of goats and sheep on the survival and germination of Mimosa tenuiflora (Willd.) Poir. seeds from the Caatinga

Abstract

Mimosa tenuiflora is a species widely distributed in the Caatinga biome as forage for herds. Goats and sheep are efficient seed dispersers and can improve seed germination. This study aimed to evaluate the passage through the digestive system of goats and sheep at different ingestion periods, and its effect on recovery, quality and anatomical aspects of M. tenuiflora seeds. For this experiment, 24 animals (12 goats and 12 sheep) were confined, and 400 seeds were provided for each animal. After the seeds supply the seeds present in the feces of the animal were periodically collected. The study was performed in a completely randomized design, in a factorial scheme 2 × 5 + 1, with two animal species (goat and sheep), five periods of seed excretion (24, 48, 72, 96, and 120 h) plus a control treatment composed of intact seeds. Recovery, seed quality, anatomy, and seedling vigor were evaluated. M. tenuiflora seeds were physically characterized as small and tended to pass quickly through the animal's digestive system. The seed recovery occurs up to 120 h for goats and 96 h for sheep after being provided, and the highest number of seeds were recovered after 48 h. The seeds collected after 120 h from goats and after 24 and 96 h from sheep showed improved germination and overcoming of seed dormancy. The anatomy analysis demonstrates that the passage through the animal digestive system promotes scarification of the seed tegument.