The use of osmoregulators and antioxidants to mitigate the adverse impacts of salinity stress in diploid and tetraploid potato genotypes (Solanum spp.)

Chemical and Biological Technologies in Agriculture

Table 6 Principal component analysis (PCA) of all studied traits of 13 genotypes of potato divided into 7 tetraploid cultivars of Solanum tuberosum (tbr), and 6 diploid clones of S. chacoense (chc) grown in vitro under conditions of high salt stress level (300 mmol L⁻¹ NaCl) and glycine betaine, proline or salicylic acid treatments

Components	Variance	Proportion	Cumulative proportion
Roots fresh weight (g)	1.255	0.082	0.871
Surface area of root (cm²)	0.927	0.062	0.933
Total root length (mm)	0.847	0.060	0.941
Number of roots/plantlet	0.956	0.077	0.864
Plantlet water content (%)	0.441	0.029	0.962
Chloride (mmol kg⁻¹ FW)	0.208	0.014	0.976
Sodium (mmol kg⁻¹ FW)	0.148	0.010	0.986
Potassium (mmol kg⁻¹ FW)	0.811	0.051	0.992
Chlorophyll (SPAD)	0.043	0.003	0.994
Catalase (U min⁻¹ g⁻¹ FW)	0.037	0.002	0.997
Peroxidase (U min⁻¹ g⁻¹ FW)	0.019	0.001	0.998
Callus fresh weight (g)	0.031	0.001	0.874
Explants forming callus (%)	0.214	0.002	0.891
Explants forming roots (%)	0.921	0.063	0.911