Seed germination methods of the Texas Northern Blackland Prairie ecotype of Sapindus saponaria L. var. drummondii (Hook. and Arn.) L.D. Benson (Sapindaceae)

Abstract

Seeds from the Texas Northern Blackland Prairie ecotype of western soapberry (Sapindus saponaria L. var. drummondii (Hook. & Arn.) L.D. Benson [Sapindaceae]) were collected, stored, pretreated (with sulfuric acid scarification and stratification), and germinated for the purposes of silviculture projects. Seeds were scarified for 0, 20, 40, and 60 min using 96% sulfuric acid (H₂SO₄) and half were stratified at 2 to 5.5 °C (35.5–42 °F) for 45 d. Results from the pretreatment methods were significantly different (stratification, P < 0.001; scarification, P = 0.039), with the greatest difference being between mean germination percentage for non-stratified and stratified seeds at 14.67% and 60.33%, respectively. For both stratification methods, the 20-min acid scarification method produced the highest germination percentages; however, germination occurred without acid scarification in both stratified and non-stratified seeds. This outcome could indicate the ecotype lacked physical dormancy or that a less volatile seed scarification pretreatment method, such as peat moss storage, could be a viable germination method.