Impact of weed flora on aphid and thrips occurrence in pepper (Capsicum annum L.) in the Strumica region

This study was conducted during 2024 and 2025 in pepper fields, at two localities in the Strumica region (Kuklish and Borievo) to determine weed species composition, their density, and their role as reservoirs of aphids and thrips.
A total of ten weed species belonging to nine botanical families were identified in Kuklish and eight species in Borievo, in and around pepper fields. The most dominant species in both localities in 2024 were Galinsoga parviflora, Chenopodium album, and Amaranthus retroflexus. In 2025, the dominant species in Kuklish were G. parviflora, C. album, and Cyperus rotundus, while in Borievo they were G. parviflora, C. album, and Capsella bursa-pastoris.
Weed density was higher in Kuklish compared to Borievo, reaching 81.6 and 62 plants/m² in 2024, and 83.4 and 70.8 plants/m² in 2025, respectively.
Aphids and thrips were recorded on both weeds and pepper plants. The number of infected pepper plants varied during the growing season. In both years, infestation by aphids and thrips was higher in Kuklish than in Borievo. In both years and at both locations, thrips were more abundant than aphids.
The results indicate a strong relationship between weed presence and pest occurrence, suggesting that weeds act as reservoirs for aphids and thrips. Effective weed management should therefore be considered an essential component of pest management strategies in pepper production.