Identification of sources of resistance to Striga gesnerioides Willd. Vatke among cowpea (Vigna unguiculata [L.] Walp) germplasm from Togo

Striga gesnerioides is one of the major biotic constraints to cowpea (Vigna unguiculata [L.] Walp) production throughout West Africa. The best way to control and limit the spread of this weed remains genetic control, but recent works have shown that all cowpea varieties commonly grown in Togo are susceptible to S. gesnerioides. This study aims to investigate the resistance response of cowpea germplasm from Togo to S. gesnerioides. A field test was performed under natural infestation followed by a pots test under artificial infestation. Genotyping was carried out with three molecular markers SSR1, 61RM2 and C42-2B, known for their linkage to S. gesnerioides resistance genes. The results have revealed three cowpea accessions, TG20_66, TG20_82 and TG20_108, phenotypically resistant to S. gesnerioides. All three resistant accessions have shown the RSG3-301 resistance gene presence. Potential resistance gene sources to S. gesnerioides exist among cowpea accessions from Togo.