Large Field Screening for Resistance to Broomrape ( Orobanche crenata Forsk.) in a Global Lentil Diversity Panel (GLDP) ( Lens culinaris Medik.).

Broomrape ( Orobanche crenata Forsk.) is a serious problem causing important losses to lentil ( Lens culinaris Medik.) production and productivity in Mediterranean countries. Despite intensive breeding activities, no resistance sources against O. crenata have been identified so far. In this study, a Global Lentil Diversity Panel (GLDP) of 1315 genotypes including local populations, landraces, accessions, improved lines and released varieties were evaluated for their resistance to O. crenata under highly infested field conditions at ICARDA Marchouch research station, Morocco. The trial was conducted according to an augmented design with repeated susceptible checks. The best-performing genotypes were selected based on the correlations between Orobanche infestation parameters and agronomic performance. Results showed significant variation ( p < 0.005) among the studied genotypes and between the tested genotypes and checks for BY, D2F, D2M, PH, EODW and NEO. Out of the 1315 tested genotypes, only (1%) showed high to moderate resistance levels to O. crenata . Most of these genotypes are improved lines originating from different breeding programs. the PCA analysis clustered all the tested genotypes into four different groups. Good resistance levels were recorded for the genotypes ILL7723, ILL 7982, ILL 6912, ILL 6415, ILL 9850, ILL 605, ILL 7915, ILL 1861 and ILL 9888 showing a parasitism index and grain yield ranging from 1.69 to 5.99 and 10.97 to 60.19 g m -2 , respectively. Person's correlation showed significant negative correlations between agronomic traits and infestation parameters. Both the path and spatial analysis showed that the D2F, NEO, D2OE, SEV and parasitism index (PI) were the strongest driver traits that influenced the seed yield (SY).