Author
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MILLER, JERRY - Retired ARS Employee |
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Charlet, Laurence |
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Submitted to: Book Chapter
Publication Type: Book / Chapter Publication Acceptance Date: 10/8/2009 Publication Date: N/A Citation: N/A Interpretive Summary: Recent breeding programs have focused on identifying germplasm with tolerance to several seed damaging insects and a stem-infesting insect; all reported as economically important pests of cultivated sunflower. These include the sunflower moth, the banded sunflower moth, the red sunflower seed weevil, and the sunflower stem weevil. This chapter reviews two breeding procedures recommended for identifying lines with improved resistance to insects attacking cultivated sunflower. The recurrent phenotypic selection breeding procedure could be utilized for selection against stem and/or foliage infesting insects and recurrent phenotypic selection with S1 line progeny evaluation could be utilized for selection for head and/or seed infesting insects. These procedures are based on the initial evidence that the resistance to the insects is quantitatively inherited. Both are based on recurrent selection and random mating, with the main objective to combine as many of the alleles controlling resistance as possible. After several cycles of selection, superior plants can be added to a breeding program’s elite line group for testing hybrid combinations or creating open-pollinated cultivars. Results from multi-year resistance trials for each of the insects are reviewed and promising germplasm identified for each of the species studied. Our investigation showed potential for developing resistant genotypes for each insect to reduce seed feeding injury by the species attacking the sunflower head or low densities of stem weevil larvae per stalk. The ability to utilize host plant resistance would provide another tool in an integrated pest management approach to prevent yield loss for the grower and increase profit. Additional effort is in progress to use the identified lines to introgress resistance genes into cultivated sunflower through conventional breeding facilitated by the use of marker-assisted selection. Technical Abstract: Recent breeding programs have focused on identifying germplasm with tolerance to several seed damaging insects and a stem-infesting insect; all reported as economically important pests of cultivated sunflower. These include the sunflower moth, Homoeosoma electellum (Hulst), the banded sunflower moth, Cochylis hospes Walsingham, the red sunflower seed weevil, Smicronyx fulvus LeConte, and the sunflower stem weevil, Cylindrocopturus adspersus (LeConte). This chapter reviews two breeding procedures recommended for identifying lines with improved resistance to insects attacking cultivated sunflower. The recurrent phenotypic selection breeding procedure could be utilized for selection against stem and/or foliage infesting insects and recurrent phenotypic selection with S1 line progeny evaluation could be utilized for selection for head and/or seed infesting insects. These procedures are based on the initial evidence that the resistance to the insects is quantitatively inherited. Both are based on recurrent selection and random mating, with the main objective to combine as many of the alleles controlling resistance as possible. After several cycles of selection, superior plants can be added to a breeding program’s elite line group for testing hybrid combinations or creating open-pollinated cultivars. Results from multi-year resistance trials for each of the insects are reviewed and promising germplasm identified for each of the species studied. Our investigation showed potential for developing resistant genotypes for each insect to reduce seed feeding injury by the species attacking the sunflower head or low densities of stem weevil larvae per stalk. The ability to utilize host plant resistance would provide another tool in an integrated pest management approach to prevent yield loss for the grower and increase profit. Additional effort is in progress to use the identified lines to introgress resistance genes into cultivated sunflower through conventional breeding facilitated by the use of marker-assisted selection. |
