The impact of PEG-induced drought stress on seed germination and seedling growth of different bread wheat (Triticum aestivum L.) genotypes

Abstract

Wheat is an important crop, used as staple food in numerous countries around the world. However, wheat productivity is low in the developing world due to several biotic and abiotic stresses, particularly drought stress. Non-availability of drought-tolerant wheat genotypes at different growth stages is the major constraint in improving wheat productivity in the developing world. Therefore, screening/developing drought-tolerant genotypes at different growth stages could improve the productivity of wheat. This study assessed seed germination and seedling growth of eight wheat genotypes under polyethylene glycol (PEG)-induced stress. Two PEG-induced osmotic potentials (i.e., -0.6 and -1.2 MPa) were included in the study along with control (0 MPa). Wheat genotypes included in the study were ‘KLR-16’, ‘B6’, ‘J10’, ‘716’, ‘A12’, ‘Seher’, ‘KTDH-16’, and ‘J4’. Data relating to seed germination percentage, root and shoot length, fresh and dry weight of roots and shoot, root/shoot length ratio and chlorophyll content were recorded. The studied parameters were significantly altered by individual and interactive effects of genotypes and PEG-induced osmotic potentials. Seed germination and growth parameters were reduced by osmotic potentials; however, huge differences were noted among genotypes. A reduction of 32.83 to 53.50% was recorded in seed germination, 24.611 to 47.75% in root length, 37.83 to 53.72% in shoot length, and 53.35 to 65.16% in root fresh weight. The genotypes, ‘J4’, ‘KLR-16’ and ‘KTDH-16’, particularly ‘J4’ better tolerated increasing osmotic potentials compared to the rest of the genotypes included in the study. Principal component analysis segregated these genotypes from the rest of the genotypes included in the study indicated that these can be used in the future studies to improve the drought tolerance of wheat crop. The genotype ‘J4’ can be used as a breeding material to develop drought resistant wheat genotypes.

Endophytic Fungal Consortia Enhance Basal Drought-Tolerance in Moringa oleifera by Upregulating the Antioxidant Enzyme (APX) through Heat Shock Factors

“…Researchers have used it to assess the drought resistance of crops during seedling establishment since it inhibits seed germination and development by lowering water potential, and the effect is more noticeable on shoots than on main roots. In vitro screening with PEG has been shown in several studies to be one of the most accurate procedures for selecting drought-tolerant genotypes based on germination indices [ 62 ].…”

Comparative Analysis of Tolerance to Salt Stress and Water Deficit in Two Invasive Weeds of the Genus Erigeron (Asteraceae)

“…The standard method to test the osmotic effect on germination is by using different concentrations of polyethylene glycol (PEG), which mimics environmental drought conditions [ 65 , 66 , 67 , 68 ]. Germination of the two species proved to be tolerant to osmotic stress, no significant differences were obtained with respect to the control up to the highest PEG concentration in E. bonariensis where 92% of the seeds and in E. sumatrensis 60% of the seeds germinated, a considerably lower reduction than under NaCl.…”

Efficacy of biological agents and fillers seed coating in improving drought stress in anise

“…Environmental factors, especially drought stress, can affect seed germination and seedling growth in such a way that activation of enzymes can be prevented in the germination stage, and plant life cycle can be disrupted in this sensitive stage (Rezayian et al, 2018;Kour et al, 2019;Mahpara et al, 2022). Different studies have shown that drought stress impacts the seed germination of various plants (Naseem et al, 2018;Khan and Bano, 2019;Zhang et al, 2019).…”