Location: Sunflower Improvement Research
Title: Efficacy of red sunflower seed weevil resistance from inbred line cms HA 488 in single-cross hybridsAuthor
Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 5/13/2024 Publication Date: 6/12/2024 Citation: Prasifka, J.R., Hulke, B.S. 2024. Efficacy of red sunflower seed weevil resistance from inbred line cms HA 488 in single-cross hybrids. Agronomy Journal. 116:2081-2084. https://doi.org/10.1002/agj2.21613. DOI: https://doi.org/10.1002/agj2.21613 Interpretive Summary: As a hybrid crop (like corn), commercial sunflowers are produced by movement of pollen from a male to a female sunflower line. A female with resistance to the red sunflower seed weevil (HA 488) and a female that is susceptible (= more easily damaged; HA 412HO) to the weevil were each pollinated using three different male sunflowers (RHA 274, RHA 464, or RHA 468) to make six hybrids. In tests during 2021-2022, the resistant female made hybrids whose seed were 40–50% less damaged than hybrids with a susceptible female parent. However, in one case (pollination by RHA 468), there was no benefit from the resistant female. The results show that both parents need to have resistance for the maximum benefit and suggest that some male lines may have previously unknown effects on damage by seed weevils. Technical Abstract: Sunflower line HA 488 is resistant to the red sunflower seed weevil, Smicronyx fulvus LeConte, with ˜ 80% less seed damage compared to susceptible lines. To determine the value of resistance in single-cross hybrids, six hybrids were created by pollinating weevil-resistant (cms HA 488) or susceptible (cms HA 412HO) inbred lines with three putatively susceptible restorer lines (RHA 274, RHA 464, or RHA 468) and artificially infesting each with 30 weevils head-1. In 2021–2022, resistant hybrids from cms HA 488 reduced seed damage by ˜ 40–50% for hybrids with RHA 274 or RHA 464. However, cms HA 488 did not reduce damage when crossed with RHA 468. Infestation of male-fertile isogenic lines HA 488 and HA 412HO with 60 weevils head-1 showed resistance remained effective at 12–20 times economic thresholds. Results confirm the value of resistance to S. fulvus for sunflower hybrids, but also suggest a need to further examine the role of male heterotic group in resistance to the red sunflower seed weevil. |