Plant Soil Environ., 2025, 71(5):293-307 | DOI: 10.17221/79/2025-PSE

Physiological and biochemical responses to cold stress in sesame (Sesamum indicum L.) during the early growth stageOriginal Paper

Ahmed A. Abbas ORCID...^1,2, Muez Berhe^1,3, Habtamu Kefale^1,4, Somaya A. Hussien², Rong Zhou¹, Ting Zhou¹, Huan Li¹, Yanxin Zhang¹, Zhongbo Guan⁵, Chris O. Ojiewo⁶, Jun You¹, Linhai Wang¹

¹ Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan, P.R. China

² Department of Agronomy, Faculty of Agriculture, South Valley University, Qena, Egypt

³ Tigray Agricultural Research Institute, Humera Agricultural Research Center, Tigray, Ethiopia

⁴ Department of Plant Science, College of Agriculture and Natural Resources, Debre Markos University, Debre, Ethiopia

⁵ Institute of Cereal and Oil Crops, Hebei Academy of Agricultural and Forestry Sciences, Shijiazhuang, P.R. China

⁶ Dryland Crops Program, International Maize and Wheat Improvement Center, World Agroforestry (ICRAF), Nairobi, Kenya

Cold stress significantly impacts sesame during its early growth stages, with varying responses observed among different genotypes. Ten genotypes were evaluated for phenotypic response to various temperatures during germination. Cold stress at 10, 12, 14, and 16 °C inhibited germination, with zero germination at 10 °C. At 14 °C, genotypes showed significant germination variation, and it was selected as the threshold temperature for assessing cold tolerance in sesame. Four genotypes were grouped into two, and each group with extreme germination responses (high and low) were selected for further biochemical and physiological studies. Genotypes V5 and V7 exhibited higher cold tolerance, better germination percentage, and seedling parameters under low temperatures, while V8 and V9 showed significant reductions, indicating cold sensitivity. Biochemical analyses revealed that cold-tolerant genotypes had enhanced activities of antioxidant enzymes, including catalase, superoxide dismutase, and peroxidase, as well as higher proline accumulation compared to sensitive genotypes. These antioxidants played a crucial role in mitigating the oxidative stress induced by cold, as evidenced by lower levels of hydrogen peroxide and malondialdehyde in the tolerant genotypes. Cold-tolerant genotypes also accumulated higher soluble sugars and protein levels, contributing to osmotic regulation and membrane stability. The findings highlight the importance of enzymatic and non-enzymatic antioxidants in cold stress tolerance, suggesting these biochemical markers could be used to identify and develop cold-resistant sesame cultivars. The results offer valuable insights into the mechanisms underlying cold tolerance and provide a foundation for breeding efforts to improve sesame cold resistance.

Keywords: colder climate; low temperature stress; oilseed crop; seed germination; soluble protein

Received: February 26, 2025; Revised: April 26, 2025; Accepted: April 28, 2025; Prepublished online: May 26, 2025; Published: May 29, 2025  Show citation