1a.Objectives (from AD-416):
1) Identify new sources of resistance and introgress resistance genes into desirable agronomic backgrounds;. 2)Phenotype mapping populations for developing new DNA markers and confirm resistance.
1b.Approach (from AD-416):
Screen soybean germplasm using standardized methods in greenhouse assay. Phenotype mapping populations from other scientists. Evaluate for presence of DNA markers using PCR reactions for Marker assisted selection.
For broadening the resistance in soybean, additional soybean germplasm is being screened for identifying new sources of resistance to soybean cyst nematode (SCN). Progenies derived from crosses AR03-361091 x PI437655; 1AR2001 x PI404166, AR05-150140_ x PI567516C and AR05-150140 x PI567568A in maturity groups ranging from I to III were evaluated for nematode resistance using DNA markers tagged to resistance in marker assisted selection. Several simple sequence markers (SSR) were identified by USDA-ARS, Jackson, TN. These included Satt 309, Satt 632, Sat_168, Satt 574, Satt 592, Satt 331 and Sat_274. We have developed modified protocols for polymerse chain reaction (PCR) used for marker assisted selection. This biotechnological method is more efficient and quicker in identifying resistant soybean lines. The greenhouse screening and development of desirable source materials are in progress, the data are shared among collaborators. ADODR monitored the research primarily through meetings, site visits, emails and conference calls.