Electric field generated by high-voltage transmission system is beneficial to cotton growth

With the increasing popularity of high-voltage transmission systems, the potential effects of environmental electric fields (EFs) generated by these systems to surrounding organisms is gradually becoming a source of public concern. Cotton is planted on a large scale all over the world and is exposed inevitably to environmental EF. In this study, cotton was exposed continuously to power frequency electric field (PF EF) of different intensities (0 kV/m, 2 kV/m, and 10 kV/m) and evaluated on agronomic traits, yield, organic matter contents, protective enzyme activities, and genes expression over time and at different stages of plant growth. We found that cotton was impressionable by EF at the seedling stage, while it was relatively insensitive at the maturity stage. Exposure to PF EF is safe and beneficial to growth and yield for cotton in our experiment. Data collected from growing cotton of plant height, functional leaf number, dry weight of plant and boll, contents of soluble sugar and total protein, and activities of superoxide dismutase and catalase exhibited a tendency to increase under the EF treatment. Transcriptional analyses showed that EF caused significant changes in the expression levels of 86 genes of cotton, and most of which were up-regulated. These differentially expressed genes are involved in carbohydrate metabolic process and various transfer proteins synthesis, and are associated with the activity of some transferases and hydrolases, providing a novel perspective for understanding molecular mechanisms underpinning the yield increase of EF to cotton.