Effects of tomato leaf handling methods on growth performance and chemical composition of Schistocerca gregaria

Abstract

Abstract Tomato leaves are an abundant agricultural waste stream; however, their use as feed is limited due to their high fiber content and the presence of toxic glycoalkaloids. This study evaluated the feasibility of utilizing tomato leaves for rearing Schistocerca gregaria (desert locust) as a source of insect protein. Locusts were fed freshly harvested leaves, leaves stored for different durations, and leaf cuttings maintained in water to preserve freshness. The results showed that storage and water-based maintenance reduced the need for daily harvesting without negatively affecting growth performance or survival, while affecting the accumulation of Cu and Zn. Notably, although tomato leaves maintained in water contained high levels of α-tomatine and dehydrotomatine, their accumulation in the locusts was reduced. Crude protein content ranged from 59.37% to 60.51%, and α-linolenic acid (C18:3, n-3) was the predominant fatty acid, accounting for 40.63% to 43.12% across treatments. Overall, tomato leaves can be stored or appropriately handled as an alternative to freshly harvested leaves without compromising locust growth, while enhancing the accumulation of Cu and Zn and reducing the frequency of daily harvesting and feeding operations.

The authors' abstract, as published at the source. Scientific Reports, 2026 · DOI ↗