Authors: Melek KİTİŞ, Mehmet AKTAŞ
Abstract: In this study, the effect of manganese fertilization and nitrogen form on the content of vitamin C in pepper (Capsicum annu L. ) was investigated. Using NFT (Nutrient Film Technique) the plants were grown in sand culture with nutrient solutions which contained different nitrogen sources (NH4)2SO4 and Ca(NO3)2 ), and different levels of manganese (0, 5, 10, 20 and 40 ppm). pH of the solutions was adjusted at 5.9 and the pots were irrigated daily with these nutrient solutions. Vegetative and generative growth of plants were decreased drastically when supplied with NH4-N as compared to those grown with NO3-N solution; fresh weight of fruits was decreased by 84.4 % and vegetative dry weight by 76.8 %. Vitamin C content of pepper fruits showed no changes with the applications of 5, 10 and 20 ppm Mn but decreased with 40 ppm Mn application as compared to that of control plants. Vitamin C content of pepper grown with NO3-N was higher than those grown with NH4-N. Manganese content of leaves was increased with the increasing level of manganese. Manganese content of leaves in plants grown with NO3-N was higher than that of plants grown with NH4-N. According to these results, manganese doesnÕt have any positive effect on vitamin C content and nitrate as a nitrogen source enhances plant growth and yield of fruit in pepper plant.