Nutrition and the protein economy in grasshoppers and locusts

1. 1. The protein and amino acid requirements of grasshoppers are similar to those of other mandibulate, phytophagous insects and are met by soluble leaf protein. 2. 2. The acquisition, digestion, assimilation and utilization of leaf protein are all subject to the negative effects of plant secondary chemicals. 3. 3. Adaptations to secondary plant chemicals have been reported in some grasshoppers but the presence of certain chemicals can have serious consequences in protein nutrition. 4. 4. Interference with protein intake, or the enforced secretion of digestive proteinases caused by some plants, results in symptoms resembling starvation. 5. 5. Negative effects on the protein economy of grasshoppers can severely reduce growth, survival and reproduction and stimulate compensatory feeding and dietary self-selection. 6. 6. Starvation or diets resulting in low protein acquisition can stimulate the reallocation of protein reserves, and ultimately tissue resorption.