Predation of Painteria leptophylla Seeds by Beetles1 and their Effects on Germination

Painteria leptophylla (DC) Britton y Rose is a rarely studied plant used in ecological restoration of arid and semi-arid zones. Its seeds are consumed by beetles of the Bruchidae family. Species that feed on the seeds were identified, the percentage of seed predation calculated during the pre-dispersal and post-dispersal stages, 2 months and a year after being collected, and germination of healthy and damaged seeds was evaluated. Merobruchus politus Kingsolver damaged 43.2% and Stator limbatus (Horn) 31.5% during pre-dispersal. Predation during post seed dispersal was 51.6% by M. politus and 50.6% by S. limbatus. Average percentage of predation 1 year after the seeds were collected was 51.6% by M. politus and 79.7% by S. limbatus. Thirty-seven percent of seeds without damage germinated and 60% were damaged by S. limbatus, with 16.6% of seeds with one emergence hole germinating and only 7% for M. politus. The percentage of predation by M. politus was greater in pre-dispersal of seeds, which might be because the species is univoltine. Thirty-seven percent of seeds without apparent insect damage germinated compared to seeds with a hole caused by S. limbatus. The greater percentage (60%) of germination, might be because damage by S. limbatus increased permeability and germination. Only 7% of seeds damaged by M. politus germinated because the larger size of the insect consumed most of the seed embryo.