biologia plantarum

Biologia plantarum 46:269-272, 2003 | DOI: 10.1023/B:BIOP.0000022263.40723.1d

Effect of Temperature Regimes on Germination of Dimorphic Seeds of Atriplex prostrata

C.T. Carter¹, L.S. Brown¹, I.A. Ungar¹

¹ Department of Environmental and Plant Biology, Ohio University, Athens, USA

Dimorphic seeds of Atriplex prostrata were removed from cold dry storage monthly over a one year period to test for fluctuations in seed dormancy and germination rate. For each seed type, four replicates of 25 seeds were exposed to four alternating night/day temperature regimes mimicking seasonal fluctuations in Ohio: 5/15 °C; 5/25 °C; 15/25 °C and 20/35 °C with a corresponding 12-h photoperiod (20 μmol m^-2 s^-1; 400 - 700 nm). We found a significant three-way interaction of seed size, temperature and month for both percent germination and the rate of germination. Large seeds showed the greatest germination at the 20/35 °C and 5/25 °C temperature regimes and small seeds at the 5/25 °C regime. Large seeds had greater germination at all temperatures as compared to small seeds. Large seeds had the fastest germination rates at 20/35 °C followed by 5/25 °C whereas small seeds had the fastest rates at 5/25 °C followed by 20/35 °C.

Keywords: endogenous rhythms; seed dormancy; seed storage

Subjects: Atriplex prostrata; dormancy; endogenous rhythms; germination; seed storage; temperature, dimorphic seed germination

Published: September 1, 2003  Show citation