Genetic Diversity of Moroccan Orobanche crenata Populations Revealed by Sequence-Related Amplified Polymorphism Markers

Abstract

Orobanche crenata Forsk. is a root holoparasitic plant that affects legume species in Mediterranean basin especially in Northern Africa. This parasitic weed is particularly problematic in faba bean (Vicia faba L.) and lentil (Lens culinaris Medik.) fields. In Morocco, development of legume resistant/tolerant genotypes is considered the most economical and ecological control strategy against O. crenata. Efficient selection of resistant/tolerant cultivars requires prerequisite knowledge of the genetic diversity of the parasite. Thus, the present study focused on the assessment of the genetic diversity among and within Moroccan O. crenata populations, growing in faba bean fields, using Sequence-Related Amplified Polymorphism markers (SRAP). This marker system proved to be a powerful and an efficient tool for the evaluation of the genetic diversity among O. crenata populations. In fact, a total of 101 markers were identified and used for the Analysis of Molecular Variance (AMOVA), among which 98 bands were polymorphic (97.02%), indicating considerable genetic variation of these O. crenata populations. However, at population level, low level of polymorphic loci was observed with a percentage ranging between 41.58% and 67.33%. The Jaccard’s similarity coefficient and Principal Coordinate Analysis (PCoA) showed a clear differentiation among O. crenata samples according to the geographical origin of each population. AMOVA analysis revealed also a large extent of variation among O. crenata populations (60%; p < 0.010). Our outputs on molecular genetics of O. crenata combined with future epidemiological studies of these populations should clarify occurrence of O. crenata pathotypes and thereby validate the relevance of using multisite screening trials during breeding programs.