Effects of Temperature, Light, and Scarification on Germination of Brownseed Paspalum Seeds

Abstract

Brownseed paspalum (Paspalum plicatulum Michx.) is an important forage grass in tropical and subtropical regions. This study investigated effects of temperature, light, and scarification on germination of seeds from Texas, Australa, South America, and Africa. Seed sources included PI-353399 (Ivory Coast), 'Bryan' (Australia), Paspalum plicatulum 600 (Columbia), and collections from De Witt and Hidalgo Counties, Texas. Untreated seeds and seeds scarified in 17 M sulfuric acid for 20 minutes were germinated under light (12 hours daily) and dark conditions at alternating temperatures of 5-15 (12 hours-12 hours), 10-20, 15-25, 20-30, 25-35, and 30-40? C for 28 days. Seeds from all sources showed similar responses to temperature for percent germination and corrected germination rate index (CGRI). Highest percent germination of Hildalgo seeds occurred at 20-30 and 25-35? C, while that of other sources occurred at 25-35 and 30-40? C. Maximum CGRI for most sources was at 30-40? C. Percent germination was generally higher in light than dark. Scarification increased percent germination and CGRI of De Witt, Hidalgo, PI-353399, and Bryan seeds. Our data indicate that brownseed paspalum seeds are adapted for warm-season germination.