Development and evaluation of host-plant-based semi-artificial diets for rearing Phytomyza orobanchia (Diptera: Agromyzidae) under controlled insectarium conditions

Phytomyza orobanchia is a specialised biocontrol agent of Orobanche spp., but its laboratory rearing remains poorly standardised. Four semi-artificial diets based on Orobanche whole-plant paste, control (T1), low (T2), standard (T3), and enriched (T4), differing in egg powder, yeast extract, glucose, and vitamins, were evaluated under insectarium conditions (25 ± 1°C, 60 ± 10% RH). Diet enrichment shortened total development from 21.1 to 16.6 days, raised pre-adult survival from 0.4 to 0.6, and increased fecundity from 9.2 to 24.5 eggs per female. Intrinsic rate of increase rose from 0.02 to 0.09 day−1. Enriched diets best support mass rearing of P. orobanchia for biocontrol.