Boron toxicity effects on the concentration of pigments, carbohydrates and nutrient elements in six non-grafted pepper cultivars (Capsicum annuum L.)

The effects of high boron concentration (5 mg L−1) on chlorophyll, carotenoid, carbohydrate, and mineral concentration in six non-grafted pepper cultivars (Arlequin, Imperial, Twingo, Odysseo, Salomon, and Gabryel) were studied. Salomon had the greatest chlorophyll, carbohydrate, and carotenoid concentration 14 and 35 days after the initiation of boron treatment, while Odysseo had the greatest boron concentration in the leaves (> 250 mg kg−1) compared to the other cultivars. At 14 days, Arlequin had the greatest boron concentration in the leaves, while Imperial, Twingo, Odysseo, and Salomon had intermediate levels, whereas the cv Gabryel had from 21 to 60% boron concentration of that found in Arlequin leaves. The greatest potassium and phosphorus concentrations in the leaves were recorded in the cultivar Imperial, while the concentrations of manganese and zinc in the leaves decreased depending on the cultivar. Iron concentration in the roots was 7–15 times greater than that of the leaves. These results indicate that chlorophyll, carbohydrate, carotenoid concentration and mineral composition in the leaves of peppers were significantly affected from both the duration of exposure to B toxicity and the genotype. This study depicts the genotypic variability associated with response to B toxicity. Interestingly ‘Salomon’ leaves had the greatest chlorophyll, carbohydrates and carotenoids concentration, which may affect fruit composition and yield, while ‘Odysseo’ accumulate more B in leaves and is more prone to B toxicity. © 2018, Indian Society for Plant Physiology.