Diversity and seasonal dynamics of wasp parasitoids associated with the edible silkworm (Borocera cajani, Lasiocampidae) in tapia woodland

Abstract

<title>Abstract</title> Study on interspecific interaction is not common in the wild edible silkworm <italic>Borocera cajani</italic>. This study explored the diversity and seasonal variation of parasitoid wasps associated with <italic>B. cajani</italic>. Weekly sampling was conducted during the rainy season (November to May 2023) using yellow pan traps and Malaise traps on Tapia woodland and its surrounding habitat, which included vegetable farming systems and agroforestry. The results revealed a high diversity of wasp parasitoids (<italic>n</italic> = 72). Only three of the fifteen species known to be parasitic were studied: <italic>Apanteles decaryi</italic> Granger (larval stage), <italic>Enicospilus evanescens</italic> Gauld &amp; Mitchell (cocoon stage), and <italic>Scelio</italic> sp1 (egg stage). The observed wasp parasitoid density doesn’t affect the density of the edible <italic>B. cajani.</italic> The rarity of the host explained also the weak diversity. Nevertheless, the diversity and seasonal variation in these wasp species highlighted the importance of the habitat as a refugee, which was highest in coffee plantation (<italic>n</italic> = 58), followed by the vegetable farming systems (<italic>n</italic> = 43), and lowest in tapia woodlands (<italic>n</italic> = 36). Compared to vegetable farming and coffee plantations, the hierarchical classification of species highlighted the distinctive diversity inherent in woodland ecosystems. However, the conservation and sustainability of the tapia woodland as a refuge and provider of insect ecosystem services may face challenges in the future due to the potential impact of chemical pesticides used on barley crops.