Peganum harmala L. is a perennial herbaceous plant and can be a future drug due to its wide medicinal purposes. Despite its economic importance, the molecular genetics of P. harmal have not yet been studied in detail. Genetic diversity of 12 P. harmala genotypes were investigated by using Inter-Simple Sequence Repeats (ISSR), PCR-RFLP of rDNA-ITS, PCR-SSCP of rDNA-ITS and Simple Sequence Repeat (SSR) markers. The level of polymorphism revealed by ITS-SSCP is the lowest, followed by ITS-RFLP then ISSR and the highest polymorphism level was reported for SSR marker. The AMOVA analysis implied that most of the variation occurred within the Populations. A value of inbreeding coefficient Fis estimated by the three co-dominant markers was nearly equal and offer an indication of the partial out-crossing reproductive system of P. harmala. Principal Coordinate Analysis (PCOA) plot revealed a clear pattern of clustering based on the locations of collected plants which coincide with the isolation by distance. The study revealed that ITS-SSCP and ISSR markers respectively were more informative than the other used markers in the assessment of genetic diversity of P. harmala. The results reflect the great diversity of P. harmala and data obtained from this study can be used for future collecting missions.

The present study describes the response of Zea mays to hematite nanoparticles (NPs) using five concentrations ranged from 500 to 8000 mg kg −1 , and Cd 2+ concentrations (110 or 130 mg kg −1 Cd 2+ ) only or combined with 500 mg kg −1 NPs, using soil culture. The endpoints measured were root/shoot growth, elements uptake, ultra-structural alterations, lipid peroxidation, some antioxidant enzyme activities, and their relative gene expressions. The results indicated that hematite NPs exhibited a dual behavior, in which 500 mg kg −1 NPs significantly enhanced maize growth, while 4000 and 8000 mg kg −1 NPs significantly increased lipid peroxidation and superoxide dismutase (SOD) activity displaying positive correlation with SOD expression in shoots (r = +0.472, p < .05). Ultrastructure micrographs revealed the appearance of aggregated NPs inside the vacuoles. The stunted growth, perturbed ultra-structure, and high lipid peroxidation were used as toxicity biomarkers for Cd 2+ . However, combined treatments of 500 mg kg −1 NPs and Cd 2+ significantly stimulated growth and glutathione reductase activity, while significantly reduced catalase (CAT) activity displaying positive correlation with CAT expression in roots (r = +0.694, p < .01). In conclusion, hematite NPs could alleviate Cd 2+ toxicity not at the level of antioxidant defense, but by affecting mechanisms of Cd 2+ detoxification.

Two forms of A. halimus shrubs: erect habit (A. halimus) and bushy habit shrub (A. schweinfurthii) are used naturally isolated by a considerable distance from each other and occupy the same area. To explore the effect of natural isolation on the genetic basis of the two forms, Start Codon Targeted (SCoT) and the phylogenetic relationships of A. halimus by sequencing ITS1-5.8S-ITS2 regions of the ribosomal DNA are used. Significant isolation-by-distance relationship was found (r = 0.62, P = 0.001). Soil factors did not influence molecular variations. The natural isolation of A. halimus habitats restricts gene flow among the populations and the observed high within-population genetic diversity (74.19%) in this species is best explained by its outcrossing behaviour, longlived individuals and overlapping generations. The UPGMA analysis of the SCoT results showed that all the studied populations were divided into two discrete genetic groups with significant separation of the two forms in Burg El-Arab area (Populations 1 and 2) and insignificant separation between two forms in El-Hammam area (population 5 and 6). The sequencing of the ITS1-5.8S-ITS2 rDNA regions also showed the insignificant separation of the two A. halimus forms. We conclude that gene flow depending on habitat fragmentation was the main factor affecting the population genetic differentiation. We suggest that the two forms do not merit specific rank in presence of interference between the two forms and absence of a breeding barrier fail to separate the different populations when they become sympatric.

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This study compared the genetic diversity within and among six naturally growing coastal and inland populations of Peganum harmala by using random amplified polymorphic DNA (RAPD) technique. Seven primers generated a total of 63 RAPD bands (loci) of which 60 (95.24%) were polymorphic across all individuals. The genetic diversity of P. harmala at the population level and species level were percentage polymorphic loci (PPL) = 42.59%, Nei's gene diversity (h) = 0.1892, Shannon information index (I) = 0.2711 and PPL = 95.24%, h = 0.3116, I = 0.4723, respectively. The value of differentiation (the coefficient for gene divergence, Gst = 0.3925) and analysis of molecular variance (AMOVA) indicated that there was a relatively high genetic differentiation within populations, and about one-six of the genetic variations occurred among populations. Analysis of fixation indices (FST) = 0.15500, p < 0.00196 showed low degree of differentiation among populations. The genetic variation in the coastal populations was higher than the variation in the inland populations. The present study suggests that the gene drift may play an important role in the differentiation of P. harmala populations. The in situ conservation of the species should focus on establishing more sites to protect the natural populations and their habitats, while the ex situ conservation needs to focus on enhancing the exchange of seeds and seedlings among populations to facilitate gene flow, exchange and recombination.

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The genetic diversity among 14 barley accessions was evaluated using seven designed primers based on long terminal repeat (LTR) retrotransposons derived from the barley genome. LTR primers amplified 96 bands of > 100- 1500 bp, of which 84 were polymorphic. The number of polymorphic fragments ranged from 5 (LTR, LTR1 and LTR6150) to 18 (Sukkula) with an average of 9.33. The highest marker index (MI) was observed with the primer Nikita (3.93) and the lowest with the primer LTR2 (1.05), with an average MI of 2.28 per primer. The insertion patterns of retrotransposones have interesting implications for genome organization in Hordeum. The Shannon diversity index with markers obtained on the accessions level was 0.45. Barely accessions are clustered according to their pedigree and caryopsis character (hulled or naked caryopsis). This study demonstrates the efficiency of IRAP markers as a genetic tool for selection of suitable accessions for breeding programs.

The current study examined the phylogenetic pattern of medicinal species of the family Apiaceae based on flavonoid groups production, as well as the overall mechanism of the key genes involved in flavonol and flavone production. Thirteen species of the family Apiaceae were used, including Eryngium campestre from the subfamily Saniculoideae, as well as Cuminum cyminum, Carum carvi, Coriandrum sativum, Apium graveolens, Petroselinum crispum, Pimpinella anisum, Anethum graveolens, Foeniculum vulgare, Daucus carota, Ammi majus, Torilis arvensis, and Deverra tortuosa from the subfamily Apioideae. The seeds were cultivated, and the leaves were collected to estimate flavonoids and their groups, physiological factors, transcription levels of flavonol and flavone production-related genes. The phylogenetic relationship between the studied species was established using the L-ribosomal 16 (rpl16) chloroplast gene. The results revealed that the studied species were divided into two patterns: six plant species, E. campestre, C. carvi, C. sativum, P. anisum, An. graveolens, and D. carota, contained low content of flavonoids, while the other seven species had high content. This pattern of flavonoids production coincided with the phylogenetic relationships between the studied species. In contrast, the phylogeny of the flavonol and flavone synthase genes was incompatible with the quantitative production of their products. The study concluded that the increment in the production of flavonol depends on the high expression of chalcone synthase, chalcone isomerase, flavanone 3 hydroxylase, flavonol synthase, the increase of Abscisic acid, sucrose, and phenyl ammonia lyase, while flavone mainly depends on evolution and on the high expression of the flavone synthase gene.