Enhancing germination of eastern gamagrass seed with stratification and gibberellic acid

• Published in: Crop science Vol. 44; no. 2; pp. 549 - 552
• Main Authors: Rogis, C, Gibson, L.R, Knapp, A.D, Horton, R
• Format: Journal Article
• Language: English
• Published: Madison, WI Crop Science Society of America 01.03.2004; American Society of Agronomy
• Subjects: Acids; Agronomy. Soil science and plant productions; Biological and medical sciences; Comparative studies; duration; forage crops; forage grasses; Fundamental and applied biological sciences. Psychology; Genetics and breeding of economic plants; Germination; gibberellic acid; Grasses; seed dormancy; seed germination; seed stratification; seed treatment; Seeds; Seeds and other planting stocks; Stratification; temperature; Tripsacum dactyloides; Monocotyledones; Germination; Gibberellin; Seed stratification; Dormancy breaking; Gramineae; Seed; Angiospermae; Plant growth substance; Spermatophyta; Fodder crop; Caryopsis; Gibberellic acid
• ISSN: 0011-183X; 1435-0653; 1435-0653
• DOI: 10.2135/cropsci2004.0549

Eastern gamagrass (Tripsacum dactyloides, L.), a warm season, perennial grass with great potential for forage and conservation uses, has a high level of seed dormancy, making establishment difficult. Stratification at 4 degrees C for 6 wk is a standard method for providing germinable gamagrass seed. Earlier research showed that gibberellic acid (GA3) increased germinability of gamagrass caryopses removed from the cupule, but was less effective when the caryopses remained in the cupule. We hypothesized that gibberellic acid together with stratification may increase germination of seed above levels obtained by stratification or gibberellic acid alone. This study assessed the germination of three seed lots of eastern gamagrass to 1 mM GA3 and exposure to 4 degrees C for 0 to 7 wk. Seed soaked in GA3 solution averaged 43% germination during the first 3 wk of stratification and was significantly higher than the germination of water soaked seed averaging 35% germination. Seed reached peak germinability after 4 wk of stratification and remained at this level during the final weeks. After 4 wk of stratification, germination levels of GA3 and water treated seed were similar at 64 to 70%. The most pronounced effect of GA3 was more rapid germination of seed in all of the stratification durations tested.