Performance, fruit quality, and shelf life of tomato (Solanum lycopersicum) grown using charred and uncharred eggshells

Abstract

Despite its widespread cultivation, challenges persist in producing tomato fruits with high quality and extended shelf life. This study focuses on the potential of eggshells as a sustainable soil amendment. The experiment was carried out to determine the growth, photosynthetic pigment concentrations, yield, shelf life, and fruit quality of tomato grown using charred eggshells (CEG) and uncharred eggshells (UCEG) (amendment) on two different soil types. The research was conducted over two cropping seasons (2022 and 2023) at Landmark University, Omu-Aran, Nigeria. Two soil types (Site A: sandy loam; Site B: sandy) were used to test the efficacy of the amendments. Ground eggshells, in both CEG and UCEG forms, were applied individually at the following concentrations: 25, 50, 75, and 100%, and in combination with each other. Standard rate (2.5 t ha −1 ) of calcium carbonate (CaCO 3 ) was applied as a check. Data on the vegetative, yield, and fruit shelf life quality were collected and subjected to analysis of variance (ANOVA) using the GENSTAT Discovery Software, Edition 4. CEG 100% had significantly ( p  ≤ 0.05) higher chlorophyll content (70.39 mg m 2 ), number of fruits (138.56), and yield (9,595.84 kg ha −1 ), while UCEG 100% had the least chlorophyll content (15.24 mg m 2 ), number of fruits (71.59), and yield (5,286.52 kg ha −1 ). Combined application of CEG 75% + UCEG 25% significantly increased the shelf life (21 days) compared to the control, which had the least number of days (9.0 days). Application of CEG 75% + UCEG 25% increased the lycopene content (1.96 mg g −1 ), vitamin A (2.24 mg g −1 ), and N, P, K, Ca, and Mg of the fruits. Tomato plants in Site A performed better than those in Site B for all the parameters tested in both years. Results of this study indicated that using CEG 75% and CEG 75% + UCEG 25% significantly improved tomato yield and shelf life. Eggshells are a low-cost, easily accessible agricultural waste product; therefore, the application of CEG 75% alone and the combined application of CEG 75% + UCEG 25% may be considered economical and environmentally friendly for tomato production.