Role of exogenous silica fertilization and genotype selection in attenuating oxidative and osmotic stress in wheat (Triticum aestivum L.) under water deficit conditions

Background & Aims Drought stress negatively affects wheat crop production worldwide. Selection of drought tolerant varieties and application of silicon (Si) can help to uplift the crop production. The present investigation was aimed to screen drought tolerant wheat varieties by evaluating the potential of Si fertilization. Methods Study was conducted in two sets of experiments, in first (hydroponic) investigation two wheat varieties out of eleven were screened out based upon agronomic parameters, membrane stability, potassium (K + ) distribution and tolerance index. The screened varieties were then subjected to different silicon fertilizers under water deficit pot conditions in second experiment and impact of Si sources was monitored via agronomic, physiological and biochemical attributes. Results Faisalabad-08 and Anaj-17 were best performing varieties in tested parameters. The silica fertilizer application improved the growth, physiological, biochemical and ionic attributes under water deficit and increased the grain yield of crop. Among tested sources, silicic acid proved best as compared to other silicates in terms of ameliorating the osmotic stress. The silicic acid application improved the root and shoot growth parameters i.e. increased plant height by 13% and grain yield by 43%, relative water contents (30%), membrane stability (46%), antioxidant activity (up to 64%), organic solutes production and silicification of cell wall by increasing Si uptake by 9 folds. Conclusion It was observed that combined use of tolerant varieties and silica fertilizer as silicic acid can uplift plant growth and production under water deficit conditions. Further field investigations are recommended to check crop economics of applied treatments.