title: Selenium Supplementation Affects Physiological and Biochemical Processes to Improve Fodder Yield and Quality of Maize (Zea maysL.) under Water Deficit Conditions.
abstract: Climate change is one of the most complex challenges that pose serious threats to livelihoods of poor people who rely heavily on agriculture and livestock particularly in climate-sensitive developing countries of the world. The negative effects of water scarcity, due to climate change, are not limited to productivity food crops but have far-reaching consequences on livestock feed production systems. Selenium (Se) is considered essential for animal health and has also been reported to counteract various abiotic stresses in plants, however, understanding of Se regulated mechanisms for improving nutritional status of fodder crops remains elusive. We report the effects of exogenous selenium supply on physiological and biochemical processes that may influence green fodder yield and quality of maize (Zea maysL.) under drought stress conditions. The plants were grown in lysimeter tanks under natural conditions and were subjected to normal (100% field capacity) and water stress (60% field capacity) conditions. Foliar spray of Se was carried out before the start of tasseling stage (65 days after sowing) and was repeated after 1 week, whereas, water spray was used as a control. Drought stress markedly reduced the water status, pigments and green fodder yield and resulted in low forage quality in water stressed maize plants. Nevertheless, exogenous Se application at 40 mg L-1resulted in less negative leaf water potential (41%) and enhanced relative water contents (30%), total chlorophyll (53%), carotenoid contents (60%), accumulation of total free amino acids (40%) and activities of superoxide dismutase (53%), catalase (30%), peroxidase (27%), and ascorbate peroxidase (27%) with respect to control under water deficit conditions. Consequently, Se regulated processes improved fodder yield (15%) and increased crude protein (47%), fiber (10%), nitrogen free extract (10%) and Se content (36%) but did not affect crude ash content in water stressed maize plants. We propose that Se foliar spray (40 mg L-1) is a handy, feasible and cost-effective approach to improve maize fodder yield and quality in arid and semi-arid regions of the world facing acute shortage of water.
authors.affiliation: Department of Agronomy, Muhammad Nawaz Sharif University of AgricultureMultan, Pakistan; Department of Agronomy, UCA and ES, The Islamia University of BahawalpurBahawalpur, Pakistan.
authors.forename: Fahim
authors.initials: F
authors.lastname: Nawaz
authors.affiliation: Department of Agronomy, UCA and ES, The Islamia University of Bahawalpur Bahawalpur, Pakistan.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Naeem
authors.affiliation: Nuclear Institute for Agriculture and Biology Faisalabad, Pakistan.
authors.forename: Muhammad Y
authors.initials: MY
authors.lastname: Ashraf
authors.affiliation: University College of Veterinary and Animal Sciences, The Islamia University of Bahawalpur Bahawalpur, Pakistan.
authors.forename: Muhammad N
authors.initials: MN
authors.lastname: Tahir
authors.affiliation: Department of Agronomy, UCA and ES, The Islamia University of Bahawalpur Bahawalpur, Pakistan.
authors.forename: Bilal
authors.initials: B
authors.lastname: Zulfiqar
authors.affiliation: Department of Agronomy, UCA and ES, The Islamia University of Bahawalpur Bahawalpur, Pakistan.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Salahuddin
authors.affiliation: Department of Agronomy, Agriculture College, Bahauddin Zakariya University Multan, Pakistan.
authors.forename: Rana N
authors.initials: RN
authors.lastname: Shabbir
authors.affiliation: Department of Agronomy, UCA and ES, The Islamia University of Bahawalpur Bahawalpur, Pakistan.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Aslam
keywords: Se; antioxidant enzymes; drought stress; fodder quality; maize; photosynthetic pigments