Evaluation of lentil cultivars and lines for resistance to Fusarium oxysporumf.sp. lentis

Abstract. Lentil (Lens culinaris Medik.) is one of the most important food legume crops in the farming and food systems of many countries, including Bulgaria. In recent years lentil fields increased in our country. Fusarium wilt caused by Fusarium oxysporum f.sp. lentis (F.o. f.sp. lentis) is a key yield-limiting factor worldwide. The major approach to control the disease is through resistance breeding. The aim of this investigation was to screen lentil cultivars and lines for resistance to F.o. f.sp. lentis. The investigations were carried out during 2013-2015. Thirty two lentil accessions were sown in 1m rows, in three replications. Barley grains (100g/m) inoculated with mix of four isolates of F.o. f.sp. lentis were used as inoculum. Disease reaction was estimated during flowering and pod filling stage according to 9 degree scale. The disease incidence (DI) of every accession was calculated according to McKinney index. Cluster analysis was used to group the accessions according to DI. ‘Genotype’ x ‘Year’ interaction was estimated by Two-way ANOVA. The results showed that middle disease incidence (MDI) was the highest in 2014 and the lowest in 2015. Our investigation confirms the results of many authors that disease incidence of F.o. f.sp. lentis on lentil was determined by the interaction of the factors ‘Genotype’x‘Year’. The cluster analysis grouped the accessions into two major classes. No resistant accessions were found. Six accessions showed MDI from 48.59 to 58.11 and they can be used in a genetic-improvement breeding program for fusarium wilt resistance