Submitted to: Proceedings Sunflower Research Workshop
Publication Type: Proceedings
Publication Acceptance Date: 2/15/1997
Publication Date: N/A
Citation: N/A Interpretive Summary: Sunflower broomrape is a serious parasite infecting the roots of plants that causes heavy losses to sunflower crops in many areas of the world. Adaptive evolution of this parasite to sunflower cultivars with resistance genes resulted in new virulent broomrape races. Sources of resistance were found in perennial wild species. This study reported the production of interspecific hybrids between two resistant wild perennial accessions and cultivated sunflower, the evaluation of their resistance to broomrape, and seed setting ability. The immune reaction in the two wild accessions and their hybrids with cultivated line indicated a simple genetic control of resistance, and the resistant plants in the progenies of the hybrids can be selected for breeding broomrape resistant lines.
Technical Abstract: Wild perennial sunflower species H. laevigatus and H. giganteus were hybridized with inbred line HA89, and the F1 plants were produced with the use of embryo rescue. The F1 plants of H. giganteus x HA89 produced sufficient backcrossed seeds for further evaluation and were highly self- incompatible. The F1 plants of H. laevigateus x HA89 had good pollen stainability and backcrossed seed set, and a low degree of self- compatibility. When tested against a virulent broomrape race collected in southern Spain, both wild accessions and their F1 hybrids with HA89 were immune, indicating total resistance of the two wild parents as well as the complete dominance of the resistance genes. Resistant backcross progenies can be further backcrossed, and the incorporation of resistance genes into cultivated lines is expected.