Inorganic and Organic Fertilization Effects on the Growth, Nutrient Uptake, Chlorophyll Fluorescence and Fruit Quality in Solanum melongena L. Plants

Plant growth, nutrient uptake and fruit quality may be influenced by fertilization practices. A 64-day greenhouse pot experiment, with a 6X1 factorial, i.e., Solanum melongena L. (cv. ‘Lagkadas’) plants, grown on soil substrate and submitted to six fertilization treatments (Patent Kali, Ammonium Nitrate + Patent Kali, Tree Branch Chips, Poultry Manure, Tree Branch Chips + Poultry Manure, and non-fertilization—CONTROL) was conducted. The objectives were to investigate the impact of fertilization on: (i) plant growth, (ii) nutrition, (iii) photosystem II activity and (iv) fruit quality. The main results were the following: a) the highest total plant and fruit biomass values were recorded in poultry manure, followed by those in the ammonium nitrate + patent kali treatment; (b) in most cases, total plant macronutrient content was significantly higher in the poultry manure-treated plants; (c) the optimum and most balanced plant nutrition, fruit total phenolic and flavonoid contents and antioxidant activity levels were achieved in the poultry manure, tree branch chips + poultry manure and ammonium nitrate + patent kali treatments; (d) significant decline in the values of the maximum quantum yield of photosystem II, performance index and fruit quality was found in the tree branch chips and CONTROL plants. It was concluded that the kind of fertilization significantly influenced biomass, nutrient uptake, chlorophyll content and fluorescence, as well as fruit quality of Solanum melongena L. plants. Thus, it should be thoroughly investigated, towards substituting high fertilization rates by manure applications and improving fruit quality, with human health benefits.