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ARS Home » Plains Area » Fargo, North Dakota » Edward T. Schafer Agricultural Research Center » Sunflower and Plant Biology Research » Research » Publications at this Location » Publication #398977

Research Project: Genetic Enhancement of Sunflower Yield and Tolerance to Biotic Stress

Location: Sunflower and Plant Biology Research

Title: Degree-day model for adult emergence of the red sunflower seed weevil

item Prasifka, Jarrad
item PANTZKE, SHAWNA - North Dakota State University
item Rinehart, Joseph - Joe
item FERGUSON, BETH - Former ARS Employee
item PRISCHMANN-VOLSETH, DEIRDRE - North Dakota State University

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 10/4/2022
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: The red sunflower seed weevil, Smicronyx fulvis LeConte, is a univoltine seed-feeding pest of cultivated sunflowers. Previous research suggests that peak populations of this pest can be avoided by planting early or early-maturing sunflower hybrids. However, no validated method to predict adult emergence has been available for this pest. Emergence of adult weevils under controlled temperatures in the laboratory allowed estimation of a lower developmental threshold and accumulated degree days for first adult emergence and 50% emergence. When the model was tested in field plots, weevils generally emerged earlier than predicted, likely because measured soil temperatures (in a state-wide weather network) are slightly cooler than what many overwintering weevils experience. This first degree-day model for S. fulvus could be improved with additional emergence (validation) data, but also by using ambient temperatures, which are more accessible than soil temperature data.