# Alternative Prey and Artificial Diet of the Multicolored Asian Lady Beetle Harmonia axyridis: A Review

## TL;DR

This paper reviews artificial diets for the lady beetle Harmonia axyridis to improve large-scale rearing for pest control.

## Contribution

The study systematically analyzes artificial diet formulations to identify key factors for efficient and cost-effective rearing of Harmonia axyridis.

## Key findings

- Current reliance on live aphids for rearing H. axyridis is costly and inefficient.
- Artificial diets can be optimized to support the beetle's entire life cycle.
- Nutritional composition of natural prey is critical for developing effective artificial diets.

## Abstract

Harmonia axyridis is a vital natural predator capable of preying upon numerous agricultural pests and are in high demand for biological control. However, large-scale provision of these beetles currently relies heavily on rearing live aphids as a food source, a method characterized by high costs, low efficiency, and unstable supply, thereby limiting the beetles’ widespread adoption. To overcome this bottleneck, we comprehensively reviewed and analyzed extensive literature on artificial diets for lady beetles. Statistical evaluations were conducted on the rearing efficacy of diverse feed formulations. Our work aims to identify key determinants of effective artificial diets, providing a solid foundation for optimizing rearing protocols and enabling large-scale propagation.

As an important natural enemy insect, Harmonia axyridis has significant biological control effects on a variety of pests such as aphids in agroforestry ecosystems. The large-scale application of H. axyridis has long been limited by the unstable supply of natural prey, poor rearing of alternative prey and artificial diets, and high costs. In this paper, we review the research progress on the effects of alternative prey and artificial diets, and present the results and shortcomings of H. axyridis rearing. Focusing on the nutritional requirements of H. axyridis and the nutrient composition of natural prey, the paper aims to analyze and optimize the core components of artificial diets, develop diet formulations that are highly efficient, low-cost, support the ladybird throughout its complete life cycle, and identify the key factors for breaking the bottleneck of large-scale reproduction of H. axyridis, with a view to facilitate the industrialization of H. axyridis, enhancing the efficacy of biocontrol, and providing references to the development of diets for other natural enemy insects.