Inventarisasi Parasitoid Larva Plutella xylostella (Lepidoptera: Plutellidae) pada Pertanaman Kubis yang Diaplikasikan dan Tanpa Aplikasi Pestisida di Desa Purba Tengah Kecamatan Purba Kabupaten Simalungun

Abstract

Plutella xylostella is the major pest of cabbage crop that can cause severe damage leading to significant yield losses. Although the main control method used by farmers is the application of chemical pesticides, this practice has the potential to reduce the population of natural enemies, including larval parasitoids that play an essential role in biological control. The objective of this study was to determine the presence, types, and parasitization rates of parasitoids associated with P. xylostella larvae in cabbage crops with and without pesticide application. The study was conducted in Purba Tengah Village, Purba District, Simalungun Regency from August to September 2025 using a survey method and pursposive sampling technique on two sampe plots, each measuring 100 m2 . Two parasitoid species were identified: Diadegma semiclausum and Cotesia vestalis. The parasitism rate 29.57% was recorded in the non-pesticide plot, while the rate in the pesticide-treated plot was 15.56%. The diversity index in both sample plots was relatively lov and dominated by D. semiclausum.