## 4 Discussion  
The present study is an original genetic diversity and structure analysis based on the dominant RAPD molecular markers of samples of \(O\). _foetida_, \(O\). _crenata_ and \(P\). _ranosa_ from different hosts and regions in Tunisia. RAPD markers were chosen based on their high polymorphism and discrimination capacity as identified in our own unpublished optimizations. Moreover, the genome of these species has not yet been sequenced, and there are no available standard molecular markers or kits that have been published to study the three species' diversity altogether. RAPD was previously used to investigate broom-rape [15; 18; 48; 49] genetic diversity in Tunisian populations [31; 49], and RADseq was used to study the genetic diversity of Tunisian \(O\). _foetida_ populations [11]. The RAPD markers applied in this study clearly showed their efficiency in revealing the polymorphism between _Orobanche_ and _Phelipanche_ species and individuals. Indeed, the PIC ranged between 0.79 and 0.92. These results agree with those of [18], who reported the effectiveness of RAPD markers in revealing the polymorphism of varied populations of _Orobanche_ spp. affecting wild hosts in Spain. Figure 4: Results of the STRUCTURE analysis’s genetic clustering (N = 34). Different colors indicate different clusters. The highest PPB was monitored for _O. creenta_, followed by 80.6% for _O. foetida_, while the lowest was detected for _P. ramosa_ (72.45%). These results were supported by the AMOVA, which revealed 70.31% genetic variability within species and only 29.69% between species, in agreement with previous results (75.4%) showing internal variation in Tunisian and Spanish _O. foetida_ populations [34; 49]. Comparable results were found in a study undertaken by [25] (the highest variability occurred between individuals as opposed to within populations based on SSR markers that screened a significant _O. creenta_ population number in Ethiopia). In our study, there was a high gene flow measured between species (Nm = 1.91). This result could be based on the high level of outcrossing (71%) of _O. creenta_[2] due to its flower morphology, with large low lips that serve as a platform for pollinators. In this context, it is well documented that such plant species possess a low rate of diversity among populations compared to self-pollinated ones. Previous research has documented that _Orobanche_ spp. and _Phelipanche_ spp. have a complex genetic structure due to their allogamous mating: _O. creenta_ from Ethiopia [25] or from Algeria [28] and _Orobanche_ spp. from Spain [24; 33; 34]. Our broomrare population structure investigation showed that, at K = 2, the model-based clustering divides the studied samples into two subgroups, the first of which grouped _O. creenta_ and _P. ramosa_ together, and the second of which included samples from all of northern Tunisia without showing any particular correlation with the geographic origin of the samples or overlapping between the two groups. Conversely, when we move to K = 3, we can distinguish three groups, and _O. foetida_ is clearly distinct from the two other species. This could be explained by the fact that an outburst of _Orobanche_ races from wild to cultivated species has been documented, as reported by many researchers in the Mediterranean regions [5; 29; 33]. For instance, _O. foetida_ was reported in Tunisia in 1905 on _Medicago truncatula_[50]; and also on common vetch [51] and lentil [52] in Morocco with variable levels of parasitism. The results of [11], utilizing Radseq to explore _O. foetida_ genetic variability, are in agreement with the grouping of _O. foetida_ separately from the other species in this study and the high genetic variability within the population without any geographic origin correlation. Indeed, both [11; 33] pinpointed the autogamous mating of Tunisian _O. foetida_ populations, affecting crop plants compared with the allogamous mating of Spanish _O. foetida_ that parasitizes wild species.