QTL Mapping For Soybean Sudden Death Syndrome (SDS) and Cyst Nematode (SCN) On a 'hartwig' x 'camp' Population.

Soybean (Glycines max (L.) Merr.) is the sixth most planted crop in the world. In the United States it occupied, in 2009, the second position with 77.5 million hectares. Estimated disease loss in some regions may vary from 10% to 16%. From this, Soybean Cyst Nematode (Heterode glycines Ichinohe) and Soybean Sudden Death Syndrome (Fusarium) are ranked respectively, first and fifth in terms of losses.

Resistant cultivars are the most effect way to control these diseases. Previous works have identified genotypes with resistance to these diseases individually and have found valuable quantitative trait loci (QTL).

The objective of this study was to map QTL conferring SDS and SCN resistance in a population developed from the cross ‘Hartwig’ x ‘Camp’. Hartwig is resistance SCN race 1 through 14 and moderately resistance to SDS, while Camp is susceptible to both.

From the F3:5 population 200 lines were phenotyped and field data was collected for SDS. Also a greenhouse screening was conducted with 3 replications. For the SCN a race 2 test was also conducted. SSR markers were used over the previous identification linkage groups.

QTL confirmation from these cross is a helpful tool for breeding purpose and leads to a better understating about the control of these diseases.