Genetic diversity among some broomrape (Orobanche) species from Egypt using SRAP and ISSR markers

Broomrape, a noxious parasitic weed from several families, causes severe damage to 
economically important vegetables and field crops in Egypt. It can reduce crop yield as much as 90 
to 100%. Identification of broomrape species based on morphological characters faces major 
difficulties. Therefore, the precise discrimination of such parasitic weed is considered the first step 
toward effective and specific weed management. Thus, in this study molecular markers were used as 
powerful and rapid identification techniques for the most major Orobanche species in Egypt. 
Sixteen sequence related amplified polymorphism (SRAP) primers and nine inter simple sequence 
repeat (ISSR) primers were employed to assess the genetic diversity among three most important 
Orobanche species. The SRAP and ISSR analyses showed that, 132 out of 170 and 80 out of 106 
markers, respectively, were detected as polymorphic markers (77.6 % and 75.4 %) among the tested 
Orobanche species. The Orobanche species were characterized by 32 genotype-specific markers, 
20 for SRAP and 12 for ISSR that would be considered as useful markers for Orobanche species. 
UPGMA cluster analysis separated the three broomrape species into two main clusters, the first 
one comprised of two species O. ramosa which infect different plants and O. aegyptiaca. While, the 
second cluster included only O. crenata. This clustering indicates that the tested species have 
common genomic segments. Our results indicated that SRAP–based molecular could be used for 
characterization of the studied broomrape species as considered more reliable and robust than 
other molecular markers used. Moreover, investigating the variability in broomrape species is 
crucial when attempting to develop weed control means.