ABSTRACT Augmentative biological control promotes sustainable food production via reducing reliance on chemical insecticides. The San Jose scale, Comstockaspis perniciosa (Hemiptera: Diaspididae), is a major pest in deciduous fruit agriculture worldwide. Surveys in Uruguay have identified a species of Aphytis to be the main natural enemy of this pest; this genus of parasitoids is mostly used for their effectiveness in regulating scale populations. This study aimed to enhance the biological control of San Jose scale via evaluating the biological characteristics of Aphytis sp. to optimise its mass-rearing. The host development stage with the highest oviposition and offspring emergence was determined. Longevity, daily egg production throughout life, and daily offspring emergence in the first 10 days of life were studied. Offspring production at different parasitoid densities was evaluated, incorporating parasitoid interference and using scales for host-feeding. Results showed greater oviposition and emergence in adult female scales compared to the second nymphal instar, regardless of scales being young or pre-reproductive females. The parasitoids had a median adult life span of 10 days, with the highest oviposition on the first day. However, offspring emergence was low during the first five days. Mass production levels approached those of individual parasitism at a density of 13 scales per parasitoid per day. These findings suggest an optimised production scheme for Aphytis sp., enhancing profitability for producers and contributing to sustainable agroecosystems via reducing the need for chemical insecticides.
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