Metabolic and physiological responses to progressive drought stress in bread wheat

• Published in: Scientific reports Vol. 10; no. 1; p. 17189
• Main Authors: Itam, Michael, Mega, Ryosuke, Tadano, Shota, Abdelrahman, Mostafa, Matsunaga, Sachiko, Yamasaki, Yuji, Akashi, Kinya, Tsujimoto, Hisashi
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 14-10-2020
• Subjects: 631/449; 631/449/2661; 631/449/2661/2146; Abscisic Acid - metabolism; Acclimatization - physiology; Adaptation, Physiological - physiology; Biomarkers - metabolism; Bread; Droughts; Humanities and Social Sciences; Metabolome - physiology; multidisciplinary; Nitrogen - metabolism; Plant Breeding - methods; Reactive Oxygen Species - metabolism; Science; Science (multidisciplinary); Soil; Stress, Physiological - physiology; Triticum - metabolism; Triticum - physiology; Water - metabolism
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-74303-6

Wheat (
Tritium aestivum
) is vulnerable to future climate change because it is predominantly grown under rain-fed conditions in drought-prone areas. Thus, in-depth understanding of drought effect on wheat metabolism is essential for developing drought-tolerant wheat varieties. Here, we exposed wheat ‘Norin 61’ plants to progressive drought stress [0 (before drought), 2, 4, 6, 8, and 10 days after withholding water] during the flowering stage to investigate physiological and metabolomic responses. Transcriptional analyses of key abscisic acid-responsive genes indicated that abscisic acid signalling played a major role in the adaptation of wheat to water deficit. Carbon isotope composition had a higher value than the control while canopy temperature (CT) increased under drought stress. The CT depression was tightly correlated with soil water potential (SWP). Additionally, SWP at − 517 kPa was identified as the critical point for increasing CT and inducing reactive oxygen species. Metabolome analysis identified four potential drought-responsive biomarkers, the enhancement of nitrogen recycling through purine and pyrimidine metabolism, drought-induced senescence based on 1-aminocyclopropane-1-carboxylic acid and Asn accumulation, and an anti-senescence response through serotonin accumulation under severe drought stress. Our findings provide in-depth insight into molecular, physiological and metabolite changes involved in drought response which are useful for wheat breeding programs to develop drought-tolerant wheat varieties.