Proteomic study of the response of Helianthus annuus to pre-sowing seed treatment by electromagnetic field and low temperature plasma

Abstract

Seed germination and seedling establishment are critical steps in agricultural production and in the maintenance of natural ecosystems. Seed treatment with non-ionizing low-level radiation (NR), such as cold plasma (CP) or electromagnetic field (EF), is a modern ecoagricultural technology for stimulation plant growth. Although the body of information on the biological effects of the NR in plants is growing, systematic in-depth analysis of the molecular mechanisms involved in the responses is needed. So far, genomic studies using mammalian cells revealed an influence of CP treatment on several biological pathways of the eukaryotic cells, however no genomic studies of plant seed response to CP or other NR have been reported to date. The response of two different varieties (confectionary and oilseed) of common sunflower (Helianthus annuus) to seed treatment with stressors was investigated in this study. The effects of pre-sowing seed treatment, using vacuum (7 min), radio-frequency electromagnetic field (5-15 min) and cold plasma (2-7 min), on germination and growth of Helianthus annuus by using germination tests, estimating plant morpho-physiological parameters and radical scavenging activity in leaf extracts. To gain an insight into the molecular mechanisms underlying effect of NR on sunflower seed germination and dormancy, we estimated changes induced in the balance of plant hormones and differential protein expression. For both plant varieties the germination and plant growth response to stressor treatment becomes stronger with increasing the time interval between the seed treatment and sowing, indicating that seed treatment by stressors activates the chain of signal transduction pathways that needs some time to develop for generating changes in gene expression pattern and numerous biochemical activities. [...]