Identification and selection of low-phosphate-tolerant germplasm in barley (Hordeum vulgare L.)

Abstract

Phosphorus (P) deficiency is one of the major constraints to crop yield worldwide, and genotypes or cultivars with high phosphate use efficiency (PUE) sustain growth when exposed to phosphate stress. Therefore, it is imperative to develop the genotypes or cultivars with high PUE. A pot experiment was conducted to evaluate the PUE among 150 barley (Hordeum vulgare L.) genotypes. Two high-tolerant and -sensitive accessions were selected. These two candidate materials were used to investigate the differences among the root morphology characteristics, antioxidant enzyme activity, inorganic phosphate (Pi) content and gene expression of HvPT5 under P-deficiency and P-sufficiency conditions. The values of these parameters were higher in the low-P-tolerant genotype than in the sensitive one. In pot experiment 1, all genotypes showed a significant difference in low-P tolerance, with variety GN121 achieving the highest tolerance, and GN42 being most sensitive. The results of this study may provide elite genetic germplasms for future work on isolation of P-related genes, and the improvement of PUE in barley. Abbreviations: PUE: phosphate use efficiency; CAT: catalase; POD: peroxidase; SOD: superoxide dismutase; DMSO: dimethyl sulphoxide; MDA: malondialdehyde; TOPSIS: technique for order preference by similarity to an ideal solution; MCDM/MADM: multi-criteria (or attribute) decision making