Exogenous application of urea and a urease inhibitor improves drought stress tolerance in maize (Zea mays L.)

• Published in: Journal of plant research 2017-05, Vol.130 (3), p.599-609
• Main Authors: Gou, Wei, Zheng, Pufan, Tian, Li, Gao, Mei, Zhang, Lixin, Akram, Nudrat Aisha, Ashraf, Muhammad
• Format: Article
• Language: English
• Subjects: Antioxidants - metabolism; Biomedical and Life Sciences; Corn; Cultivars; Drought resistance; Droughts; Enzyme Activation; Hydrogen peroxide; Hydrogen Peroxide - metabolism; Life Sciences; Malondialdehyde - metabolism; Metabolites; Organophosphorus Compounds - antagonists & inhibitors; Osmoregulation; Osmoregulation - physiology; Peroxidases - metabolism; Photosynthesis; Pigments, Biological; Plant Biochemistry; Plant Ecology; Plant growth; Plant Leaves - growth & development; Plant Leaves - metabolism; Plant Physiology; Plant Proteins - metabolism; Plant Sciences; Polyethylene Glycols - pharmacology; Reactive Oxygen Species - metabolism; Regular Paper; Spraying; Stress, Physiological; Superoxide Dismutase - metabolism; Superoxides - metabolism; Urea; Urea - metabolism; Urease - drug effects; Water - metabolism; Water content; Water stress; Zea mays - drug effects; Zea mays - growth & development; Zea mays - metabolism; Zea mays - physiology
• ISSN: 0918-9440; 1618-0860
• DOI: 10.1007/s10265-017-0933-5

Drought is believed to cause many metabolic changes which affect plant growth and development. However, it might be mitigated by various inorganic substances, such as nitrogen. Thus, the study was carried out to investigate the effect of foliar-applied urea with or without urease inhibitor N-( n -butyl) thiophosphoric triamide (NBPT) on a maize cultivar under drought stress simulated by 15% (w/v) polyethylene glycol 6000. Foliar-applied urea resulted in a significant increase in plant dry weight, relative water content, and photosynthetic pigments under water stress condition. Furthermore, the activities of superoxide dismutase (SOD), peroxidase (POD), and hydrogen peroxidase (CAT), were enhanced with all spraying treatments under drought stress, which led to decreases in accumulation of hydrogen peroxide (H 2 O 2 ), superoxide anion ( O 2 · - ) and malondialdehyde (MDA). The contents of soluble protein and soluble sugar accumulated remarkably with urea-applied under drought stress condition. Moreover, a further enhancement in above metabolites was observed by spraying a mixture of urea and urease inhibitor as compared to urea sprayed only. Taken together, our findings show that foliar application of urea and a urease inhibitor could significantly enhance drought tolerance of maize through protecting photosynthetic apparatus, activating antioxidant defense system and improving osmoregulation.