Assessing the Impact of Compost and Compost Tea on Water Stress Mitigation in Tomato Plants Under In Vitro and Pot Conditions

Abstract

Water scarcity is a major constraint to agricultural productivity, particularly in arid and semi-arid regions. This study evaluated the effects of gardening waste-based compost and compost tea (CT) on tomato (Solanum lycopersicum L.) plants subjected to osmotic and water deficit stress. The first experiment assessed seed germination and early growth under polyethylene glycol (PEG)-induced osmotic stress. An inverse correlation between PEG concentration and seed and plant development was found. CT improved the germination rate and early seedling development under moderate stress (2% PEG). The second experiment examined the effect of compost and CT on tomato growth in a 45-day pot trial under three irrigation levels: 100%, 60%, and 40% field capacity (FC). Compost-treated plants consistently showed significantly greater growth and biomass accumulation across all FC levels, especially under moderate water stress. In contrast, CT-treated plants showed a general reduction in growth parameters. In addition, there was a positive association between compost treatment and multiple growth traits, particularly under reduced irrigation conditions. These findings underscore the beneficial effects of compost on plant performance under drought conditions.