Diversity and Host Association of Aphid Species on Vegetable Crops in Peri-Urban Farms in Jos, Plateau State, North Central Nigeria

Aphids are economically destructive pests of vegetable crops, causing direct feeding damage and transmitting plant viruses that significantly reduce yields. Plateau State, with its temperate highland climate, is a major vegetable production zone supplying markets throughout Nigeria, making aphid management a priority for farmers in the region. This study surveys aphid species diversity and host associations on six common vegetable crops in peri-urban farms around Jos Metropolis. Aphid colonies will be sampled weekly from cabbage, tomato, pepper, carrot, spinach, and garden egg across 30 farms over one growing season. Aphids will be cleared, mounted, and identified using morphological keys with reference to current taxonomic literature. Host specificity and infestation intensity will be documented. Natural enemy observations will be recorded concurrently. The study will apply regression analysis to examine the relationship between aphid density and observed leaf damage scores. This work adds to limited documentation of vegetable aphid fauna in Nigeria's highlands. Results are expected to identify Brevicoryne brassicae and Myzus persicae as dominant species, with host specialization varying by vegetable type. Extension recommendations will focus on early monitoring, intercropping strategies, and conservative pesticide application to protect natural enemies. Keywords: aphid diversity, vegetable crops, Jos Plateau, host associations, pest management