Development of Artificial Diets for Mass Rearing of Eldana saccharina Walker (Lepidoptera: Pyralidae): A Systematic Review

Abstract

Sugarcane is a commercial crop and prime source of sugar contributing about 60% of worldwide sugar demand. Production of the crop in Africa is threatened by the African sugarcane stalk borer (Eldana saccharina), which can reduce yields up to 0.5 t/ha, even with just one larva present in the field. Management attempts using chemical and biological control have all proved futile against E. saccharina. To date no reliable method that has reduced the pest populations to economically acceptable levels after infestations have been detected. However, the use of Sterile Insect Technique (SIT) has of recent years become a promising option against several Lepidopteran pests making it an alternative to consider against E. saccharina. The effective exploitation of E. saccharina for SIT heavily relies on mass-rearing of the pest in the laboratory. Thus, developing a suitable diet is of utmost consideration prior to attempted rearing. This systematic review examined available literature on various sources and databases (Google, Google Scholar, EBSCOhost, AGORA, Research4Life, and Research Gate) from 1978 to 2024, focusing on diet formulations. Out of 69 considered relevant articles only six of them specifically addressed mass-rearing of E. saccharina. Several diets formulated to include crushed sugarcane had minimal success and led to high mortality rate. Success was recorded with diets that included sterol compounds which contribute to large-sized females, essential for successful SIT application. Unfortunately, all works on diet formulation are based on experiments conducted in South Africa, highlighting a significant research gap in other countries particularly Sub-Saharan Africa. The ingredients used in successful diets are costly and often unavailable in many countries, making SIT adoption challenging. Attempt to address these challenges should explore locally-available and cost-effective ingredients for diet formulation enabling effective SIT application against E. saccharina, paving a way to reliable control of the pest on sugarcane.