Oviposition Preference and Larval Host Range of the Sugarbeet Root Maggot

Abstract

The sugarbeet root maggot, Tetanops myopaeformis Röder, is native to North America; however, its main crop host, sugarbeet, Beta vulgaris L., was introduced to the continent from Europe. This study involved an investigation of the attractiveness of cultivated crops and native North American weed species for oviposition by T. myopaeformis and the relative suitability of these potential host plant species for larval development, thus potentially shedding light on the native and current host range of this pest. Females preferred to oviposit near the following plant species: sugarbeet; spinach, Spinacia oleroceae L.; palmer amaranth, Amaranthus palmeri S. Watts.; common lambsquarters, Chenopodium album L.; redroot pigweed, Amaranthus retroflexus L.; and spear saltbush, Atriplex patula L. Larval survival was highest on spinach, followed by sugarbeet, and spear saltbush (all belonging to the family Chenopodiaceae). This suggests that species within this family likely served as native host plants for T. myopaeformis before the introduction of sugarbeet to North America. Lower larval numbers on common lambsquarters, redroot pigweed, and Palmer amaranth suggest that these species are sub-optimal hosts, despite being attractive for oviposition. Additional findings showed a general lack of oviposition preference by T. myopaeformis females for sunflower, Helianthus annuus L., and common ragweed, Ambrosia artemisiifolia L. These results provide further insights into the rapidly successful host preference shift by this insect to sugarbeet.