Location: Plant Germplasm Introduction and Testing Research
Title: Alfalfa NPGS germplasm – Leafhopper resistanceAuthor
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Irish, Brian |
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BRUMMER, CHARLES - University Of California, Davis |
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Samac, Deborah - Debby |
Submitted to: Book Chapter
Publication Type: Book / Chapter Publication Acceptance Date: 5/15/2024 Publication Date: 5/21/2024 Citation: Irish, B.M., Brummer, C.E., Samac, D.A. 2024. Alfalfa NPGS germplasm – Leafhopper resistance. In: Volk, G.M., Chen, K., Byrne, P., editors. Plant Genetic Resources: Success Stories. Fort Collins, CO: Colorado State University. https://colostate.pressbooks.pub/pgrsuccessstories/chapter/alfalfa-npgs-germplasm-leafhopper-resistance/. Interpretive Summary: Potato leafhopper is one of the most economically important pests of alfalfa in the eastern half of the United States and Canada, causing death of seedlings, adult plant stunting, and significantly reduced forage yield and quality. This leads to significant economic losses to producers. Prior to 1980s, there were no cultivars with resistance to potato leafhopper and the pest was managed by early harvest, leading to reduced yield, or with use of insecticides. In the 1980s, a hairy trait conferring resistance to potato leafhopper was discovered in USDA ARS National Plant Germplasm System wild and domesticated alfalfa, which was introgressed into elite breeding lines resulting in cultivars with this pest resistant trait. A significant acreage of potato leafhopper resistant cultivars with the hairy trait is now grown in the U.S. where the insect pest occurs. The use of leafhopper resistant cultivars in alfalfa production, especially when pest pressure is high, is an environmentally friendly tool that increases safety by reducing or eliminating the need for insecticide use while reducing crop production costs. Technical Abstract: Potato leafhopper (PLH; Empoasca fabae) is one of the most economically important pests of alfalfa in the eastern half of the United States and Canada, causing seedling mortality, adult plant stunting, and significantly reduced forage yield and quality. The damage causes reduced yield and quality in the alfalfa crop during mid-summer cuttings, and if severe, to subsequent crop harvests that year leading to significant economic losses to producers. Prior to 1980s, there were no cultivars with resistance to PHL and the pest was managed by early harvest of the herbage, leading to reduced realized yield potential, or with use of insecticides. In the 1980s, a glandular haired (trichome) trait conferring resistance to PLH was discovered in USDA ARS National Plant Germplasm System alfalfa and crop wild relative plant introductions, which was introgressed into elite breeding lines resulting in cultivars with this pest resistant trait. Although difficult to quantify precisely, a significant acreage of PLH resistant cultivars with the glandular-haired trait is grown in the U.S. where the insect pest occurs. The use of leafhopper resistant cultivars in alfalfa production, especially when pest pressure is high, is an environmentally friendly tool that increases safety by reducing or eliminating the need for insecticide use while reducing crop production costs. |