Seed germination and early seedling growth of barley at negative water potentials

Authors: Springer, Timothy; Mornhinweg, Dolores - Do

Submitted to: Agronomy
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/21/2019
Publication Date: 10/23/2019
Citation: Springer, T.L., Mornhinweg, D.W. 2019. Seed germination and early seedling growth of barley at negative water potentials. Agronomy. 9(11):671. http://doi.org/10.3390/agronomy9110671.
DOI: https://doi.org/10.3390/agronomy9110671

Interpretive Summary: Moisture stress affected the percentage of seed germination, rate of seed germination and seedling growth of six winter barley (Hordeum vulgare) lines. USDA scientist at Woodward and Stillwater, Oklahoma conducted an experiment to determine the effects of simulated dry conditions on barley seed germination, germination rate, and seedling growth. We found percentage seed germination to decrease when conditions became drier. Percentage seed germination ranged from 95% for moist conditions to 1% for the driest conditions. Seedling growth was adversely affected by drier conditions as well. Four-day old seedling roots ranged from 59mm long in moist conditions to 7mm in the driest conditions. Four-day old seedling shoots ranged from 36mm long in moist conditions to less than 1mm in the driest conditions. The data suggested that enough genetic variation is present in barley to effectively breed cultivars with improved germination in dry conditions. Understanding the germination characteristics of seeds under dry conditions will assist plant breeders in the development of cultivars with the capacity to germinate and establish under a variable climate.

Technical Abstract: The impacts of climate change may increase the duration and frequency of droughts which would have deleterious effects on crop establishment and production. The objectives of this study were to determine the effects of moisture stress on seed germination and seedling growth of six winter barley (Hordeum vulgare L.) lines. Twenty-five seed of each line were germinated at water potentials of –2.0, -1.6, –1.2, -0.8, -0.4, and 0 MPa for 4- and 7-days. The experimental design was a factorial arrangement of treatments (barley lines and water potential treatments) in a randomized block replicated four times and repeated twice. The percent seed germination at 4- and 7-d varied with barley line (P < 0.01), water potential treatment (P < 0.01), and barley line × water potential treatment interactions (P < 0.01). The germination rate varied with water potential treatment (P < 0.01), and barley line × water potential treatment interactions (P < 0.01). The data indicated that sufficient genetic variation was present to effectively breed cultivars with improved germination at negative water potentials. Understanding the germination characteristics of seed at negative water potentials will assist plant breeders in the development of cultivars that produce seeds with the capacity to germinate and establish under a variable climatic condition.