Salinization/sodification of soil and physiological dynamics of sunflower irrigated with saline–sodic water amending by potassium and farm yard manure

• Main Authors: M. Ashraf, S. Muhammad Shahzad, N. Akhtar, M. Imtiaz, A. Ali
• Format: Article
• Language: English
• Published: IWA Publishing 2017-12-01
• Series: Journal of Water Reuse and Desalination
• Subjects: amendment; brackish water; physiological activities; salinity; sodicity; sunflower
• Online Access: http://jwrd.iwaponline.com/content/7/4/476

Sunflower (Helianthus annuus L.) plants were grown with saline–sodic water (SSW) by treating with potassium (K @ 100 and 200 mg K2O kg−1 soil) and farm yard manure (FYM @ 5 and 10% of soil, w/w). Irrigation with untreated SSW caused soil salinization/sodification, leading to an increase in electrical conductivity (EC) of 165% and sodium adsorption ratio (SAR) 100% with the subsequent increase of 736% in shoot Na+, a decrease of 52% in shoot K+ and 94% in shoot K+:Na+ratio compared to canal water. SSW also decreased physiological activities: 31% relative water content (RWC), 34% membrane stability index (MSI), 51% protein, 33% chlorophyll and 58% photosynthetic rate compared to canal water. Integrated application of K and FYM, at higher level, decreased soil EC by 54% and SAR 43%, and shoot Na+ 57% with a corresponding improvement in soil organic matter 166%, shoot K+ 360%, shoot K+:Na+ratio 987%, RWC 34%, MSI 37%, protein 60%, photosynthetic rate 102%, superoxide dismutase 92%, peroxidase 78% and catalase 52% compared to SSW without K and/or FYM. In conclusion, exogenous application of K and FYM could be a promising approach to use brackish water in agriculture on a sustainable basis.