Influence of crop spacing, post-harvest packaging and storage period on physico-biochemical quality of leafy lettuce (Lactuca sativa L.) grown on hydroponic system

Lettuce ( Lactuca sativa L.) is one of the world’s most popular and economically important leafy vegetables, valued for its high nutritional benefits, versatile culinary applications, and efficient, fast-growing production methods. The nutritional quality of lettuce is influenced by multiple factors, including pre-harvest cultivation and post-harvest handling practices. The highly perishable nature of the crop after harvest reduces its shelf life, which creates challenges for storage, distribution, and marketing. As a result, this study assessed the combined effects of pre-harvest plant spacing (10 and 20 cm) and post-harvest packaging material (Biorientated polypropylene packaging “BOPP” and Expandable polystyrene sheet + polyvinyl chloride wrap “EPS + PVC”) on the quality of leafy lettuce cultivated in vertical nutrient film technique hydroponic system. It was found that the 10 cm plant spacing in combination with BOPP anti-fog packaging sustained the most fresh-cut lettuce moisture content, wilting, yellowing and browning, as well as maintained the lowest levels of oxygen, with a simultaneous increase in carbon dioxide. This resulted in improved nutritional and phytochemical qualities of the fresh produce for up to six days of storage. This emphasizes the importance of integrating pre- and post-harvest strategies to enhance the shelf life and quality of hydroponically grown lettuce.