The effect of temperature on the germination of Arabidopsis thaliana seeds

Abstract

Arabidopsis thaliana is a model organism widely used by researchers to study many different plant traits. To understand how rapid climate change and rising global temperatures could affect flowering plant growth, crop production and agriculture, A. thaliana has been used to observe the progression of germination of cotyledons and hypocotyls at different temperatures. Three incubation temperature treatments were selected: one at optimal condition for growth at 20°C, one lower than optimal condition, 11°C, and one higher than optimal condition, 30 °C. Four replicates, each containing 10 A. thaliana seeds, were incubated at each temperature. Cotyledon and hypocotyl growth were observed under a dissecting microscope daily and measured using ImageJ image processing software. On day two, the lengths of cotyledons and hypocotyls were very similar as germination had not occurred yet. On day five, the mean germinated length of the hypocotyls and cotyledons for the 11°C and 30 °C conditions were similar, at 0.1784mm and 0.2435mm respectively. In contrast, A. thaliana grown at 20°C had significantly more growth, measuring 2.031mm on average. On day eight, similar patterns were observed, with mean growth lengths of 1.2627mm, 3.2599mm and 1.0644mm for the 11°C, 20°C and 30°C conditions respectively. We conclude that non-optimal growth temperatures inhibit the germination of Arabidopsis thaliana as shown by the reduced cotyledon and hypocotyl length.