Selenium (Se) Regulates Seedling Growth in Wheat under Drought Stress

Fahim Nawaz,Ejaz Ahmad Waraich,Rashid Ahmad,Rana Nauman Shabbir,Muhammad Yasin Ashraf

doi:10.1155/2014/143567

Abstract

Selenium (Se) is an essential micronutrient with a range of physiological and antioxidative properties. Reports regarding effect of Se application on plants growth and development are not consistent. The identification of effective Se dose and application method is crucial for better understanding of Se translocation within crop plants under drought stress. The present study aimed at investigating the role of Se supplementation in improving the drought tolerance potential of wheat at early growth stages. Two wheat genotypes (Kohistan-97 and Pasban-90) were grown in plastic pots (8 × 12 cm) in green/wire-house experiments. Results demonstrated that the growth and biomass of seedlings increased at high Se foliar concentrations and decreased at low and high Se fertigation levels. The seedlings exhibited the highest values for plant height stress tolerance index (PHSI), root length stress tolerance index (RLSI), dry matter stress tolerance index (DMSI), and fresh matter stress tolerance indices (FMSI) at Se fertigation level of 7.35 μM, whereas Se foliar treatment of 7.06 μM resulted in maximum values for these indices. The seedlings foliarly sprayed with Se maintained higher DMSI and FMSI than those fertigated with Se which suggests that Se foliar spray is more effective than Se fertigation for improving drought tolerance.

Highlights

Drought stress has emerged as the single most critical threat to world food security
The maximum plant height stress tolerance index (PHSI) value (86%) was noted in seedlings fertigated with 7.35 μM Se, whereas low PHSI values were recorded at high (11.03 μM and 14.70 μM) or low levels (3.68 μM) of Se fertigation (Figure 1)
Nonsignificant differences were recorded between genotypes in both Se supply methods (Se fertigation and Se foliar spray) for PHSI (Figure 1)

Summary

Introduction

Drought stress has emerged as the single most critical threat to world food security. It seriously limits agricultural productivity, especially in areas where rainfall is limiting or unreliable, so improving yield under limited water conditions has become a crucial target for arid and semiarid regions of the world [1,2,3]. The physiological and antioxidant properties of selenium (Se) have increased the curiosity of many biologists in recent past. It does not take part in various vital metabolic processes in plants, it may help to reduce the damage under physiological stresses [7, 8]. It may regulate water status [18] and increase biomass production [19] by the activation of antioxidant apparatus of water stressed plants [20, 21]

Methods

Results

Discussion

Conclusion