Striga weed is considered to be the greatest biological constraint to food production in sub-Saharan Africa (SSA). Striga hermonthica is the most widespread among the species in the semi-arid tropical African zones. Seven populations of S. hermonthica were collected from five regions on sorghum and millet in Sudan and investigated with 12 microsatellite markers. Host speciﬁcity or geography may play important roles in shaping the population structure of S. hermonthica. 108 fragments were detected across all primer combinations and numbers per each primer ranged from 2 to 18 with average 9.1 fragments. The genetic diversity among the seven populations was moderate as revealed by the Nei‟s genetic distance values which, ranged from 0.387 to 0.919 with an average of 0.724. Genetic differentiation between populations was relatively high, and all populations were signiﬁcantly different from each other. FST values ranged from 0.00 to 0.643 indicating high differentiation. Geography appeared to play a signiﬁcant role in shaping the genetic diversity of S. hermonthica.
Keywords: Striga hermonthica, SSR, host speciﬁcity, geography, Sudan.