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.

Heat tolerance around flowering in wheat identified as a key trait for increased yield potential in Europe under climate change

“…An absolute tolerance to high temperatures is certainly unachievable. However, it has been shown that susceptibility to high temperatures during anthesis and grain filling varies among wheat cultivars (Alghabari et al , 2014; Vara Prasad and Djanaguiraman, 2014). Therefore, impacts of heat stress on future yields could be expected between these two extreme cases.…”

“…It has been shown that wheat is particularly sensitive to extreme cold and hot temperatures during the reproductive stage (Saini et al , 1983; Marcellos and Single, 1984; Alghabari et al , 2014; Vara Prasad and Djanaguiraman, 2014). With global warming, the frequency of high temperatures occurring around anthesis is predicted to increase in Europe (Semenov and Shewry, 2011).…”

Changes in Water Status, Membrane Stability and Antioxidant Capacity of Wheat Seedlings Carrying Different Rht‐B1 Dwarfing Alleles under Drought Stress

“…), or on grain yield at adult stage (Alghabari et al. ). Using a set of wheat Rht near‐isogenic lines, growth reduction by dehydration was shown to be inversely related to plant size.…”

High-Temperature-Induced Defects in Tomato (Solanum lycopersicum) Anther and Pollen Development Are Associated with Reduced Expression of B-Class Floral Patterning Genes

“…At later stages of anther and pollen development, however, B-class gene expression is maintained by gibberellin (GA) via degradation of DELLA proteins, which act as repressors of the B-class MADS-box genes [50,51]. Notably, a GA-hyposensitive mutant in wheat has recently been shown to be hypersensitive to high temperature regarding seed set [52] and among rice cultivars, the ability to maintain pollen viability under high temperatures was shown to correlate with higher contents of GA [53]. …”