Journal of Applied Entomology (2020) 144, 632-636

Jarrad R. Prasifka (2020)
Susceptibility of sunflower inbred lines and putative resistance sources to Smicronyx fulvus LeConte (Coleoptera: Curculionidae)
Journal of Applied Entomology 144 (7), 632-636
Abstract: The red sunflower seed weevil, Smicronyx fulvus LeConte (Coleoptera: Curculionidae), is a primary seed-feeding pest of cultivated sunflowers, Helianthus annuus L., in North America. Host plant resistance is one tool available to complement insecticide-based management of S. fulvus. Artificial infestations of 30 adult weevils per head were used to determine whether variation for susceptibility to S. fulvus exists in previously released inbred lines, and how a new weevil-resistant line, HA 488, compares with other putative sources of resistance. Correcting for the number of seeds per head, 13 older inbred lines showed variation in per cent seed damage from 20% to 38%, with two lines (HA 412 HO, HA 821) being more damaged than most of the tested lines. Among four putative resistance sources, HA 488 was significantly less damaged (5%) than two previously identified open-pollinated varieties (PI 170424, PI 253417, with 13%–14% seed damage), while the source of the resistance in HA 488, PI 431542, was statistically intermediate (12%). The resistance available in HA 488 is a marked improvement, potentially reducing damage per weevil by two thirds or more, but additional work on genetic markers for resistance, economic thresholds and basic weevil biology (e.g. degree-day models for adult emergence) is needed to support implementation of integrated pest management for this key sunflower pest.
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Link to article at publishers website
Database assignments for author(s): Jarrad R. Prasifka

Research topic(s) for pests/diseases/weeds:
resistance/tolerance/defence of host

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Smicronyx fulvus	Sunflower (Helianthus annuus)	U.S.A. (mid N)