Registration of AR11SDS Soybean Germplasm Resistant to Sudden Death Syndrome, Soybean Cyst Nematode, and with Moderate Iron Deficiency Chlorosis Scores

Genetically resistant crops are effective strategies for crop production and the soybean [Glycine max (L.) Merr.] program against pathogens at Iowa State University (ISU) breeds germplasm possessing resistance to Iowa pests. Sudden death syndrome (SDS) caused by Fusarium virguliforme, soybean cyst nematode (SCN; Heterodera glycines Ichinoe), and iron deficiency chlorosis (IDC) are Iowa yield deterrents. AR11SDS (Reg. No. GP-399, PI 675224) was developed at ISU, Project 4403, Agronomy Department, ISU Research Foundation (ISURF) Docket # 3999. AR11SDS is an F-3-derived bulk of 60 F-8:9 plants from the cross 'Ripley' x 'IA2036'. Ripley resistance to SDS and IA2036 resistance to SCN were crossed in Iowa. Generations were advanced at the ISU research site, University of Puerto Rico, PR. From 2003 to 2006, AR11SDS yield was evaluated. Resistance to SDS and SCN was screened in greenhouses and on SCN-infested fields. Calcareous soils were used to screen IDC. Five SDS resistance quantitative trait loci (QTLs) were from Ripley, and one SCN QTL was from IA2036. Average seed yield on SCN-infested soil (3891 kg ha(-1)) was similar to the high-yielding SDS-susceptible 'IA2068' (3658 kg ha(-1)) although lower on non-SCN soil, similar in yield to SDS-susceptible 'IA2065', and superior to SDS-susceptible 'Dwight'. AR11SDS is of early-mid maturity group II, adapted to 40 to 42 degrees N latitude, and is highly resistant to SDS, resistant to SCN (Race 3, HG Type 0, and 7), and moderately resistant to IDC (score 2.4). These traits and its yield and agronomic performances make AR11SDS a unique source for SDS breeding in the northern US soybean region.