Germination and morphology of Sapindus saponaria L. (Sapindaceae) seeds for their sustainable use

Objective: To characterize morphological traits and to evaluate different pre-germinative treatments to break the physical dormancy of Sapindus saponaria L. seeds. Design/methodology/approach: Seeds of S. saponaria were collected in the municipality of Cintalapa de Figueroa, Chiapas. Seed length, seed width and seed coat width were measured. The weight of 100 seeds, germination percentage, and purity were assessed. The following pre-germinative treatments were established: (T1) Hot water (80 °C) until room temperature; (T2) Hot water (80 °C) until room temperature followed by cold water shock (14 °C) until room temperature; (T3) Mechanical scarification; (T4) Mechanical scarification plus soaking in water for 24 hours (at room temperature); and (T5) Control. A completely randomized experimental design with four replications was used. Results: This study found that S. saponaria seeds average 10.3 mm in length, 10.2 mm in width, and have a seed coat thickness of 1.2 mm. Mechanical scarification yielded the highest germination percentage (23.3%). This finding is significant given that the untreated germination percentage in this species is moderate to low. However, this result is lower than percentages documented in studies using chemical treatments. Limitations on study/implications: Despite the low germination percentage, the advantages of the treatments implemented in this study is that they are cost-effective. Findings/conclusions: It is necessary to expand assessments of pre-germinative treatments, both locally and regionally, to develop effective strategies for the sustainable management of Sapindus saponaria while harnessing its economic and medicinal potential.