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Research Article

Spinach Germination and Seedling Growth Promoted by Electrical Stimulation via Negative Air Ions
Joung-Il An1†
,
Moon-Sun Yeom12†
,
Myung-Min Oh13*
1Division of Animal, Horticultural, and Food Sciences, Chungbuk National University, Cheongju 28644, Korea
2Protected Horticulture Research Institute, National Institute of Horticultural and Herbal Science, Rural Development Administration, Haman 52054, Korea
3Brain Korea 21 Center for Smart GreenBio Convergence and Sustainable Regional Development, Chungbuk National University, Cheongju 28644, Korea
*Corresponding Author
†These authors contributed equally to this work.
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Abstract

Electrical stimulation, also referred to as ‘electroculture’ is an agricultural technique used to enhance crop productivity and improve quality. In the present study, electrical stimulation via air ionization–defined as the exposure of plants to electrically charged air molecules (negative air ions)–was applied using negative air-ion generators placed around spinach seeds and seedlings to boost germination and early growth. Three levels of the air ionization treatment–low (LA, 3.6 × 105 ion·cm-3), moderate (MA, 5.1 × 105 ion·cm-3), and high (HA, 8.3 × 105 ion·cm-3)–were applied, along with a control (Con). After 14 days of the air ionization treatment, the germination rate in LA was 36% higher than that in Con. In addition, the LA treatment for 12 h increased gibberellic acid levels and decreased the abscisic acid content. At the seedling stage, the shoot fresh weight in the HA treatment was at least 31% higher than that in the Con at days 7, 14, and 21. The 4C nuclear DNA content of spinach leaves was higher in the LA treatment than in the Con. Furthermore, with regard to the cell division phases, the ratios of the S and G2M phases were high in all air ionization treatment groups, indicating active cell division. The results suggest that a specific level of electrical stimulation improves both spinach seed germination and seedling stages.

Keywords
air anion
cell division
electric field
electroculture
phytohormone
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Information
  • Publisher :KOREAN SOCIETY FOR HORTICULTURAL SCIENCE
  • Publisher(Ko) :한국원예학회
  • Journal Title :Horticultural Science and Technology
  • Journal Title(Ko) :원예과학기술지
  • Received Date : 2025-12-16
  • Revised Date : 2026-01-06
  • Accepted Date : 2026-01-08
  • DOI :https://doi.org/10.7235/HORT.20260001
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