Date of this Version
The red sunflowerseed weevil, Smicronyx fulvus LeConte (Coleoptera: Curculionidae), is a major insect pest of sunflower in North Dakota, South Dakota, and Minnesota. Economic damage is caused by the larvae which are internal seed feeders. During the 1992-1995 growing seasons, sunflower accessions were artificially infested and evaluated for resistance to the red sunflower seed weevil. Accessions 170411, 253417, and 170424 were resistant to the red sunflower seed weevil. Morphological types within accessions170411 and 170424 varied for seed and pollen color and resistance to the red sunflower seed weevil. The resistant variant of accession170424 had 45% of the seed damage of the susceptible type. In accession 170411, damage in the resistant type was 55% of the susceptible. Antixenosis was the major resistance mechanism detected in accessions 170411 and 170424.