The salinity of soil is among the most important abiotic stresses which limit agricultural productivity worldwide. The effects of salinity on growth, nutrient partitioning, chlorophyll, leaf relative water content, osmolytes accumulation and antioxidant compounds of pepper (Capsicum annuum L.) cultivars ('Granada', 'Goliath' and 'Nobili'), widely used in Cameroon, were investigated. Plants were subjected to four levels of NaCl (0, 50, 100 and 200 mM) at early seedling growth stage of plant development. Application of NaCl treatment led to a significant increase in total soluble sugars, proline, soluble proteins, total free amino acids content, peroxydase and superoxide dismutase activity and total phenolic content in salt-tolerant 'Granada' and 'Nobili' compared to salt-sensitive 'Goliath' and untreated plants, on the contrary, decreased in root dry weight, shoot dry weight, number of leaves, shoot length, stem diameter, total leaf area, chlorophyll and leaf relative water content in 'Goliath' at low salinity level. Flavonoid content, K, Ca and Mg concentrations were significantly reduced with increasing salinity in all cultivars. The highest Na concentrations were detected in the leaves while the lowest were recorded in the roots of 'Goliath' at high salinity level. The salt sensitivity of 'Goliath' seems to be increased osmotic adjustment through the strongly accumulation of Na in leaves while the salt tolerance of 'Granada' was related to its induce of antioxidative enzyme system more efficiently, resulting in higher osmolytes accumulation under salinity. 'Granada' was more tolerant and stable in physiological and biochemical traits suggesting that it could be grown in salt-affected soils.

Cowpea seeds are recognized to contain some anti-nutritional factors that reduce their nutritional values. The objective of this work was to evaluate the content of tannins, flavonoids and phytic acid of cowpea seeds and to study their genetic control by using generation's means analysis (GMA). F1 and F2 generations as well as backcross populations (BC1 and BC2) were produced in three hybrid combinations by crossing six selected lines. Variation among tested varieties was from 55.12 mg GAE/100 g dw (24-125B) to 233.92 mg GAE/100 g dw (IT97K-573-1-1) for tannins, 60.90 mg/100 g dw (24-125B) to 557.91 mg/100 g dw (BR1) for phytates and 363.64 mg RE/100 g dw (24-125B) to 453.93 mg RE/100 g dw (BR1) for flavonoids. Broad-sense heritability values (0.86 to 0.99), narrow-sense heritability values (0.06 to 0.50) and analysis of gene effects suggested that the antinutrients studied were controlled by additive and non-additive genes. Significant epistatic effects were found in several crosses and a duplicate type of epistasis was observed. These results suggested that breeding for increased tannins, flavonoids and phytates contents in cowpea seeds would be quite efficient through recurrent selection and selection in advanced generations.

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Salinity stress is the main abiotic constraints limiting crop yield worldwide. We investigated the effect of salt stress on growth, dry weight partitioning, chlorophyll content, mineral uptake, biochemical constituents and non-enzymatic antioxidant compounds of white pepper (Piper nigrum L.). White pepper seeds were planted in polythene bags previously filled with sand and supplied with a nutrient solution in a greenhouse during six weeks as a completely randomized design. Plants were subjected to four different concentrations of NaCl (0, 50, 100 and 200 mM). Supplies of intake doses of NaCl in the culture medium significantly decreased the dry biomass, stem height, leaf area and chlorophyll contents respectively from 100 mM NaCl. Mineral elements (K, Ca and Mg) significantly (P < 0.001) decreased in plant organs. The different biochemical constituents (proline, total soluble carbohydrates, soluble proteins and total free amino acids), total phenolic and flavonoids contents significantly (P < 0.001) increased from 50 mM NaCl. The accumulation of biochemical constituents in the leaves increased the osmotic potential of white pepper and could be considered as biochemical indicators of early selection and osmotic adjustment ability for salt tolerant plants. The planting of white pepper in salt affected soils could be encouraged for better development.