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Holoparasitic broomrape weeds (Orobanche and Phelipanche spp.) are a major biotic constraint limiting the production of important food crops. Parasitism caused by Phelipanche spp. is considered to be a serious threat, particularly in the Mediterranean region. In this study, the broomrape species collected from infested fennel fields in Sid L'Mokhtar in the Central West of Morocco was described and identified morphologically and molecularly. For molecular identification, 700 bp ITS regions were PCR-amplified from two representative individuals, OA and OY-4. The obtained sequences exhibited more than 99% similarity with the P. schultzii sequence (MT026593). In addition, maximum likelihood analysis placed our species with other referred P. schultzii in the same clade. Through molecular analysis, the broomrape species attacking fennel was identified as P. schultzii. This is the first record of the broomrape species P. schultzii parasitizing fennel (Foeniculum vulgare syn. Foeniculum officinale) in Morocco. Therefore, it should be considered that this parasite could spread to other cultivated fields causing severe yield losses, requiring urgent action through efficient control measures to avoid further spread of this parasitic weed. [ABSTRACT FROM AUTHOR]

Hybridization and polyploidy are major drivers of plant evolution. In Centaurea (Asteraceae), both mechanisms are frequent and lead to reticulate evolutions. However, in the Western Mediterranean section, Seridia studies are scarce. In this section, Centaurea aspera forms a complex including four European diploid and one Moroccan autotetraploid subspecies, an allopolyploid, and hybrids among them. Here, we aimed to delimit the different taxa, identify any introgressions, and discuss their evolutionary history. Samples of all taxa were analysed using 1688 SNPs obtained through GBS and were morphologically characterized. Three genetically well-differentiated clusters were observed, corresponding to the allopolyploid C. seridis, the diploid C. aspera and the cryptic autotetraploid C. aspera ssp. gentilii, which is proposed to be considered as a species. Centaurea seridis showed a high isolation by distance, a greater morphological variability, and a lack of interspecific gene flow. Diploid and autotetraploid C. aspera individuals were morphologically similar, and some introgressions were detected in Southern Spain, where new forms may promote diversification. This gene flow might have taken place during the Messinian and before autopolyploidization occurred in Morocco. In the C. aspera complex, current interspecific barriers are strong, while polyploidization may provide a better adaptation to drier environments. [ABSTRACT FROM AUTHOR]

Cercospora Leaf Spot is the most important foliar disease that affects sugar beet crops all over the world. The recent study focuses on the effect of isolation methods, light, and the culture medium on the development of Cercospora beticola Sacc. The results underlined that abundant sporulation occurred in the alternating 12-hr light/dark, but few spores were produced in the continuous darkness. The two medium PDA and SBLEA had no statistically significant effect on sporulation rate or fungal speed growth. From four isolation techniques, only the scraping by scalpel pseudostromata on old dry leaf technique has a lower rate of growth and had no sporulation in the tow media and under the tow light regime. Also, isolates collected from the four major sugar beet cultivating agro-ecologies (Gharb; Doukkala; Tadla; Moulouya), over two growing seasons (2017–2018), were characterized according to morphological and genetic traits. The genetic difference was studied by four RAPD primers and three DAMD. The outcome resulted in high band diversity depending on the used primer even for isolates from the same beet production area. The isolates showed a high diversity of morphological and molecular traits and the comparison between the classification of the two diversities did not reveal any connection between genetic and morphological diversity. Further studies may explore the source of this high genetic diversity, such as long infected seed transmission or C. beticola mycelium anastomosis. [ABSTRACT FROM AUTHOR]