Abstract Detail

Crops and Wild Relatives

Transfer of sclerotinia basal stalk resistance from annual sunflower crop wild relatives into cultivated sunflower (Helianthus annuus L.).

Sclerotinia basal stalk rot (BSR) is caused by Sclerotinia sclerotiorum, a necrotrophic fungus capable of causing a stem disease that is a major yield-limiting factor in global sunflower production. Sunflower is the only host species that is susceptible to BSR as a root infection. BSR resistance breeding is relatively complex, since resistance is controlled by multiple genes each with a small effect. To increase the level of resistance and genetic diversity of cultivated sunflower, annual sunflower crop wild relatives were evaluated for resistance to Sclerotinia BSR with four species showing high levels of tolerance that were introgressed into cultivated sunflower. Interspecific hybrids were screened in artificially inoculated field trials over six environments. Eight interspecific germplasm lines based on four wild annual species were identified: CMS 89 x PAR-1673 (Texas); CMS 451 x PRA-HIR 437 (Texas); CMS 441 x ANN-1 (Texas); CMS 441 x ANN 412-2 (Texas); CMS 466 x ANN 14 (Aust.); CMS 451 x ARG-130-1 (Mozb.); CMS 467 x ARG 130-2 (Mozb.); and CMS 451 x ARG 1 (S. Afr.). Average disease incidence (DI =percent of plants infected) for CMS 89 x PAR-1673 (Texas) was 11%; CMS 451 x PRA-HIR 437 (Texas) (16%); CMS 441 x ANN-1 (Texas) (5%); CMS 441 x ANN 412-2 (Texas) (6%); CMS 466 x ANN 14 (Aust.) (8%); CMS 451 x ARG-130-1 (Mozb.) (11%); CMS 467 x ARG 130-2 (Mozb.) (4%); and CMS 451 x ARG 1 (S. Afr.) (5%). The susceptible hybrid checks Cargill®270 had a DI of 60% and Hybrid 894 (47%), while the tolerant hybrid check Croplan®305 had 20%. The recurrent parents, CMS HA 89 was 36%, CMS 441 (20%), CMS 451 (44%), CMS 466 (19%), and CMS 467 (16%). The germplasm lines can be used in sunflower breeding programs to introgress Sclerotinia BSR resistance genes into adapted inbred lines for developing hybrids with a more efficient, durable, and environmentally friendly host plant resistance.

1 - United States Department Of Agriculture, USDA-ARS-N CROP SCI LAB, 1616 Albrecht Blvd N, Fargo, ND, 58102, United States

Keywords:
Genetic resources
species distributions
disease resistance.

Presentation Type: Poster
Number: PCW001
Abstract ID:63
Candidate for Awards:None