TY - JOUR

T1 - Independent and combined effects of soil warming and drought stress during anthesis on seed set and grain yield in two spring wheat varieties

AU - Weldearegay, Dawit Fisseha

AU - Yan, F.

AU - Jiang, D.

AU - Liu, Fulai

PY - 2012

Y1 - 2012

N2 - Increase in soil temperature together with decrease in soil moisture during anthesis of spring wheat (Triticum aestivum L) crops is predicted to occur more frequently in a future climate in Denmark. The objective of this study was to investigate the responses of two Danish spring wheat varieties (Trappe and Alora) to soil warming (H), drought (D) and both (HD) during anthesis. The plants were grown in pots in a climate-controlled glasshouse. In H, the soil temperature was increased by 3 °C compared with the control (C). In both D and HD treatments, the plants were drought-stressed by withholding irrigation until all of the transpirable soil water had been depleted in the pots. Results showed that, particularly under D treatment, Alora depleted soil water faster than Trappe. In both varieties, flag leaf relative water content (RWC) was significantly lowered, while spikelet abscisic acid (ABA) concentration was significantly increased by D and HD treatments. Compared with the C plants, D and HD treatments significantly reduced ear number, ear to tiller ratio, shoot biomass, grain yield, harvest index and seed set but hardly affected tiller number and 1000-kernel weight, whereas H treatment alone only decreased shoot biomass and reduced seed set. When analysed across the varieties and the treatments, it was found that the reduction in seed set was closely correlated with the increase in spikelet ABA concentration, indicating that D and HD treatments induced greater spikelet ABA concentrations might have caused seed abortion. It was concluded that the grain yield reduction under D and HD treatments during anthesis in spring wheat is ascribed mainly to a lowered seed set and wheat varieties (i.e. Alora) with more dramatic increase in spikelet ABA concentration are more susceptible to D and HD treatment.

AB - Increase in soil temperature together with decrease in soil moisture during anthesis of spring wheat (Triticum aestivum L) crops is predicted to occur more frequently in a future climate in Denmark. The objective of this study was to investigate the responses of two Danish spring wheat varieties (Trappe and Alora) to soil warming (H), drought (D) and both (HD) during anthesis. The plants were grown in pots in a climate-controlled glasshouse. In H, the soil temperature was increased by 3 °C compared with the control (C). In both D and HD treatments, the plants were drought-stressed by withholding irrigation until all of the transpirable soil water had been depleted in the pots. Results showed that, particularly under D treatment, Alora depleted soil water faster than Trappe. In both varieties, flag leaf relative water content (RWC) was significantly lowered, while spikelet abscisic acid (ABA) concentration was significantly increased by D and HD treatments. Compared with the C plants, D and HD treatments significantly reduced ear number, ear to tiller ratio, shoot biomass, grain yield, harvest index and seed set but hardly affected tiller number and 1000-kernel weight, whereas H treatment alone only decreased shoot biomass and reduced seed set. When analysed across the varieties and the treatments, it was found that the reduction in seed set was closely correlated with the increase in spikelet ABA concentration, indicating that D and HD treatments induced greater spikelet ABA concentrations might have caused seed abortion. It was concluded that the grain yield reduction under D and HD treatments during anthesis in spring wheat is ascribed mainly to a lowered seed set and wheat varieties (i.e. Alora) with more dramatic increase in spikelet ABA concentration are more susceptible to D and HD treatment.

U2 - 10.1111/j.1439-037X.2012.00507.x

DO - 10.1111/j.1439-037X.2012.00507.x

M3 - Journal article

VL - 198

SP - 245

EP - 253

JO - Journal of Agronomy and Crop Science

JF - Journal of Agronomy and Crop Science

SN - 0931-2250

IS - 4

ER -