In Japan, the scarcity of land resources has long driven the intensification of agriculture, where the use of chemical pesticides and fertilizers was once a common choice to maximize crop yield per unit area. However, this model has also led to increasing environmental pressure, prompting Japanese society to turn its attention toward more sustainable agricultural pathways aimed at protecting the health of soil, water sources, biodiversity, and even entire rural ecosystems. As public concern over food safety and pesticide residues grows, safer and more environmentally friendly biopesticides have gradually become a shared expectation among both farmers and consumers.

In response to this trend, the Japanese government launched its landmark "Green Food System Strategy" in 2021. This strategy, analogous to Europe's "Farm to Fork" plan, sets ambitious goals: to cut the risk-weighted use of chemical pesticides by 50% by 2050 and to expand organic farming to one million hectares, equivalent to a quarter of Japan's total farmland. The core of this strategy is to enhance the resilience and sustainability of agricultural production through a series of innovative measures, such as promoting Integrated Pest Management (IPM), optimizing pesticide application techniques, and developing novel alternatives. Within this grand blueprint, biopesticides are regarded as one of the key tools for implementing IPM principles and replacing chemical pesticides.
I. Japan's Unique Definition and Regulation of Biopesticides
Globally, "biopesticide" is often a broad concept, generally referring to agricultural preparations derived from biological resources. However, in its actual pesticide management, Japan adopts a stricter and narrower standard for the definition of "biopesticide." According to its regulations, Japanese biopesticides specifically refer to products whose active ingredients are "living organisms." This primarily includes antagonistic microorganisms, entomopathogenic microorganisms, entomoparasitic nematodes used for pest and disease control, and predatory or parasitic arthropods (i.e., natural enemies).
This precise definition means that many biologically-derived substances classified as biopesticides internationally—such as plant extracts, pheromones, agricultural antibiotics, and mineral oils—are not included in the official "biopesticide" category in Japan, although they are registered and used. They are classified into a separate category. To illustrate this classification more clearly, the table below (Table 1) details the types of biologically-derived substance pesticides that are registered in Japan but do not fall under the official "biopesticide" category.
Despite this regulatory distinction, when promoting organic agriculture, both officially defined biopesticides and a selection of approved biologically-derived substance pesticides are considered important tools for green production. The "List of Inputs for Organic Farming" published by Japan's Ministry of Agriculture, Forestry and Fisheries (MAFF) reflects this pragmatic approach. As shown in Table 2, this list not only covers all officially defined biopesticides but also includes various approved plant-derived, mineral-derived, and biochemical pesticides, which together form the toolbox available for products certified under the Japanese Agricultural Standard (JAS) for organic farming. Most of these products are exempt from the establishment of an Acceptable Daily Intake (ADI) and Maximum Residue Limits (MRLs).

II. Overview of Biopesticide Registration and Application in Japan
As a pioneer in the R&D and application of biopesticides, Japan has established a mature registration management system. As of 2023 statistics, there are 99 effective biopesticide formulations registered in Japan, derived from 47 different active ingredients (all of which are living organisms), accounting for approximately 8.5% of all registered pesticide active ingredients in the country.
In terms of application, the use of these biopesticides is highly concentrated: 35 ingredients are used as insecticides (including 2 nematicides), and 12 are used as fungicides. Currently, there are no registered living organism biopesticides for herbicidal or other purposes.
Application of Natural Enemy Biopesticides
Among all biopesticides, natural enemies hold a significant position, with 22 active ingredients registered. These natural enemy products can be classified into two types based on their mode of action:

1. Predatory insects and mites: These directly prey on pests, such as ladybugs, lacewings, and various predatory mites.
2. Parasitic insects: These lay their eggs inside pests, and their larvae feed on the host, eventually killing it. Examples include various parasitoid wasps.
These natural enemy products play a crucial role in modern agriculture, especially in intensive production environments like greenhouses for vegetables, flowers, and fruits. They are widely used to control common pests such as aphids, whiteflies, thrips, leaf miners, and spider mites. It is worth noting that Japan's biopesticide registration list is dynamic. Some previously registered natural enemy products (such as Amblyseius cucumeris, Orius strigicollis, etc.) have expired due to non-renewal of their registration, reflecting the continuous evolution of the market and technology.