Growth parameters, mineral distribution, chlorophyll content, biochemical constituents and non-enzymatic antioxidant compounds of white yam (Dioscorea rotundata (L) var. gana) grown under salinity stress.

Soil salinity has a negative impact on crop production over the world. The effect of salt stress on growth, chlorophyll content, mineral distribution, biochemical constituents and non-enzymatic antioxidant compounds of white yam (Dioscorea rotundata (L) var. gana) cultivar regularly consumed in Cameroon were investigated. Plants were subjected to four different levels concentrations of NaCl (0, 50, 100 and 200 mM), with 0 mM NaCl as a control. The supply of intake doses of NaCl in the culture medium significantly (P < 0.001) decreased the dry biomass (roots and shoots), growth parameters (number of leaves, noose diameter, leaf area and stem height) and chlorophyll contents from 100 mM NaCl. Mineral elements (K, Ca and Mg) and K/Na ratio significantly (P < 0.001) decreased in roots and shoots with increasing salinity. The higher sodium (Na) concentrations were recorded in shoots than in roots. The different biochemical constituents (proline (PRO), total soluble carbohydrates (CH), soluble proteins (PR) and total free amino acids (FAA)) and non-enzymatic antioxidants compounds (total phenolic (TP) and flavonoids (FLA) contents) significantly (P < 0.001) increased from 50 mM NaCl. The main strategy in cv. gana seems to increase osmotic adjustment through high accumulation of CH, PR, FAA and PRO in the leaves and they could eventually be considered as biochemical indicators of early selection and osmotic adjustment ability for salt tolerant plants. The gana variety could be encouraged to be planted on salt affected soils for the better development in salty areas.