Molecular identification of the parasitoids Trichospilus diatraeae, Palmistichus elaisis, Tetrastichus howardi and Trichogramma pretiosum

Parasitoid wasps play a fundamental role in the biological control of pests, but their morphological identification can be limited due to their small size and the high similarity between species. The aim of this study was to molecularly identify Trichospilus diatraeae, Palmistichus elaeisis, Tetrastichus howardi and Trichogramma pretiosum using genome sequencing. The samples consisted of adult specimens preserved in absolute ethanol, extracted using the DNeasy Blood & Tissue kit (Qiagen), and sequenced on the Illumina Novaseq 6000 platform. Bioinformatics tools were used were used for quality control, variant detection and principal component analysis (PCA) and support vector modeling (SVM). Aphelinus certus was the most suitable reference genome, showing the lowest number of fixed variants and the greatest alignment between species. Four specific variants were identified for T. diatraeae, five for T. pretiosum, four for P. elaeisis and two for T. howardi, allowing them to be identified. The analysis of variants in simulated samples confirmed the robustness of the genetic markers. The results represent an advance in the molecular identification of these parasitoids.