The impact of selenium application on enzymatic and non-enzymatic antioxidant systems in Zea mays roots treated with combined osmotic and heat stress
Küçük Resim Yok
Tarih
2017
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
TAYLOR & FRANCIS LTD
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Selenium (Se), regarded as an antioxidant, has been found beneficial for plants growing under stressed conditions. To investigate whether the Se application helps to improve stress tolerance, sodium selenite (Na2SeO3 . 5H(2)O, 5-15 mu M)was hydroponically applied to Zea mays variety OSSK-713-roots under heat and/or PEG-induced osmotic stress (25% PEG-6000) for 8 h. The individual/combined stress caused accumulation of reactive oxygen species (ROS). While only superoxide dismutase (SOD) increased with heat stress alone, the activities of SOD, catalase (CAT) and ascorbate peroxidase (APX) increased under PEG exposure. The combination of these stresses resulted in an induction of both SOD and CAT activities. Lipid peroxidation (TBARS) levels were also high in all the stress treatments, especially under the combination treatment. Addition of Se not only improved the activities of SOD, APX and glutathione reductase (GR) in stress-treated roots, but it also changed the activities of monodehydroascorbate reductase (MDHAR) and dehydroascorbate reductase (DHAR). The findings reveal that Se has a positive effect on heat and/or osmotic stress mitigation mainly by regulating the ascorbate-glutathione cycle, especially in PEG-treated plants. Under the combined stress treatment, addition of 5 mu M of exogenous Se was most effective.
Açıklama
Anahtar Kelimeler
Antioxidant system, combined stress, heat stress, PEG-induced osmotic stress, selenium, Zea mays
Kaynak
ARCHIVES OF AGRONOMY AND SOIL SCIENCE
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
63
Sayı
2
