High intrinsic seed Zn concentration improves abiotic stress tolerance in wheat

Abstract

Abiotic stresses are threatening wheat productivity across the globe, which is often associated with nutrient deficiencies. Zinc (Zn) is involved in many physiological processes of plants, and high intrinsic seed Zn concentrations may help to improve the resistance of wheat to abiotic stresses. Three separate experiments evaluated the effect of intrinsic seed zinc on bread wheat resistance to abiotic stresses, viz. waterlogging, drought and salinity. One-week-old wheat seedlings raised from seeds containing either 49 mg (high), 42 mg (medium), or 35 mg (low) Zn kg−1 grain were exposed to waterlogging or drought stress for one week or until harvest. Salinity stress was applied at sowing for one week or until harvest. Plants with high intrinsic seed Zn performed better than those with medium or low Zn concentrations under each stress, including lower malondialdehyde contents and total antioxidant activities and more proline. The grain yield in plants from high, medium and low seed Zn concentrations increased by 10.5–48%, 12.2–21.5% and 7.7–21% under waterlogging, drought and salinity stress, respectively. Plants with high intrinsic seed Zn concentrations produced higher wheat grain yields than those with lower levels under abiotic stress by reducing oxidative damage and improving the growth and uptake of nutrients.