Plant Soil Environ., 2020, 66(7):334-344 | DOI: 10.17221/169/2020-PSE

Physiological and antioxidant responses of cultivated and wild barley under salt stressOriginal Paper

Jabeen Zahra^*,1,2, Hussain Nazim², Irshad Faiza², Jianbin Zeng², Ayesha Tahir¹, Guoping Zhang²

¹ Department of Biosciences, COMSATS University Islamabad (CUI), Islamabad, Pakistan

² Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, P.R. China

Saline soil is a critical environmental problem affecting crop yield worldwide. Tibetan wild barley is distinguished for its vast genetic diversity and high degree of tolerance to abiotic stress, including salinity. The present study compared the response of antioxidant defense system in the XZ16 wild and CM72 cultivated barleys to salt stress. Wild barley was relatively more tolerant than cultivated CM72, salt-tolerant cultivar, with less Na⁺ uptake and more K⁺, Ca²⁺, and Mg²⁺ retention in plant tissues. The results of diaminobenzidine (DAB) and nitroblue tetrazolium (NBT) staining showed that XZ16 had significantly lower H₂O₂ and O₂^- concentrations than a salt-sensitive cultivar Gairdner, suggesting that the salt-tolerant genotype suffer from less oxidative damage. Moreover, XZ16 and Gairdner had the highest and lowest anti-oxidative enzyme activities and proline content in plant tissues. In addition, the microscopic examination revealed that DNA damage in cv. Gairdner was closely correlated to oxidative stress, representing that more reactive oxygen species accumulation in plants tissues leads to subsequent DNA damage. The present results show that higher salt tolerance of wild barley XZ16 is attributed to less Na⁺ accumulation and stronger anti-oxidative capacity.

Keywords: Hordeum vulgare L.; superoxide radical; hydrogen peroxide; toxic effect; antioxidant enzyme

Published: July 31, 2020  Show citation