title: Effect of Rht alleles on wheat grain yield and quality under high temperature and drought stress during booting and anthesis.
abstract: The present study examined the effects of gibberellin semi-sensitive reduced height (Rht) alleles on wheat grain yield and quality under high temperature and drought stress during booting and anthesis stages. Near-isogenic lines (NILs) of winter wheat (Rht (tall), Rht-B1b, Rht-D1b, Rht-B1c, Rht-8c, Rht-D1c, Rht-12) having background of Mercia and Maris Widgeon cultivars were compared under variable temperatures (day/night: 20/12, 27/19, 30/22, 33/25, 36/28, and 39/31 °C) and irrigation regimes. Pots were transferred to controlled thermal conditions (Saxcil growth chamber) during booting and anthesis stages and were maintained at field capacity (FC) or had water withheld. High temperature (>30 °C) and drought stress for seven consecutive days during booting and anthesis stages reduced the grain yield, while increased nitrogen (N) and sulphur (S) concentrations. A 50 % reduction in grain yield was fitted to have occurred at 37.4 °C for well-watered plants and at 31.4 °C for drought-stressed plants. The N and S concentrations were higher for severe dwarfs, whereas no significant differences were observed between tall and semi-dwarfs in Mercia. In the taller background (Maris Widgeon), N and S concentrations were significantly higher compared with that in Mercia. In Mercia, the severe dwarf Rht-D1c had higher Hagberg falling number (HFN) and sodium dodecyl sulphate (SDS) sedimentation volume. In both backgrounds, semi-dwarfs and severe dwarfs had higher HFN. Moreover, the SDS sedimentation volumes in Maris Widgeon were also higher than that in Mercia. Greater adaptability and improved grain quality traits suggested that severe dwarf Rht alleles are better able to enhance tolerance to high temperature and drought stress in wheat.
authors.affiliation: Department of Arid Land Agriculture, Faculty of Meteorology, Environment & Arid Land Agriculture, King Abdul Aziz University, Jeddah, 21589, Saudi Arabia.|School of Agriculture Policy and Development, University of Reading Earley Gate, PO Box 237, Reading, RG6 6AR, UK.
authors.forename: Fahad
authors.initials: F
authors.lastname: Alghabari
authors.affiliation: Department of Arid Land Agriculture, Faculty of Meteorology, Environment & Arid Land Agriculture, King Abdul Aziz University, Jeddah, 21589, Saudi Arabia.
authors.forename: Muhammad Zahid
authors.initials: MZ
authors.lastname: Ihsan
authors.affiliation: College of Resources and Environment, Huazhong Agricultural University, Wuhan, Hubei, 430070, China. shussain@webmail.hzau.edu.cn.|College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China. shussain@webmail.hzau.edu.cn.
authors.forename: Saddam
authors.initials: S
authors.lastname: Hussain
authors.affiliation: College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.
authors.forename: Ghulam
authors.initials: G
authors.lastname: Aishia
authors.affiliation: Department of Arid Land Agriculture, Faculty of Meteorology, Environment & Arid Land Agriculture, King Abdul Aziz University, Jeddah, 21589, Saudi Arabia.
authors.forename: Ihsanullah
authors.initials: I
authors.lastname: Daur
mesh_terms: D000483:Alleles; D003681:Dehydration / Q000235:genetics; D055864:Droughts; D002523:Edible Grain / Q000235:genetics / Q000254:growth & development; D017343:Genes, Plant; D005875:Gibberellins / Q000502:physiology; D006358:Hot Temperature; D056626:Inflorescence / Q000235:genetics / Q000254:growth & development; D014908:Triticum / Q000235:genetics* / Q000254:growth & development
chemical_list: D005875:Gibberellins
keywords: Gibberellin-sensitive alleles; Grain quality; Hagberg falling number; Heat stress; Nitrogen contents