DNA-based RAPD (Random Amplification of Polymorphic DNA) markers have been used extensively to study genetic diversity and relationships in a number of fruit crops. In this study, 10 (7 commercial mango cultivars and 3 accessions) mango genotypes traditionally grown in Suez Canal and Sinai region of Egypt, were selected to assess genetic diversity and relatedness. Total genomic DNA was extracted and subjected to RAPD analysis using 30 arbitrary 10-mer primers. Of these, eleven primers were selected which gave 92 clear and bright fragments. A total of 72 polymorphic RAPD bands were detected out of 92 bands, generating 78% polymorphisms. The mean PIC values scores for all loci were of 0.85. This reflects a high level of discriminatory power of a marker and most of these primers produced unique band pattern for each cultivar. A dendrogram based on Nei's Genetic distance co-efficient implied a moderate degree of genetic diversity among the cultivars used for experimentation, with some differences. The hybrid which had derived from cultivar as female parent was placed together. In the cluster, the cultivars and accessions formed separate groups according to bearing habit and type of embryo and the members in each group were very closely linked. Cluster analysis clearly showed two main groups, the first consisting of indigenous to the Delta of Egypt cultivars and the second consisting of indigenous to the Suez Canal and Sinai region. From the analysis of results, it appears the majority of mango cultivars originated from a local mango genepool and were domesticated later. The results indicated the potential of RAPD markers for the identification and management of mango germplasm for breeding purposes.

Biodiesel is an eco-friendly renewable fuel that can be derived from microalgae. Maximization of biomass and lipid productivities are considered the main challenges for algal biodiesel production. Since conventional batch cultures are time-, space-, and reagent-consuming with many restrictions to apply many replicates, microfluidic technology has recently emerged as an alternative low-cost and efficient technology with high throughput repeatability and reproducibility. Different applications of microfluidic devices in algal biotechnology have been reported, including cell identification, sorting, trapping, and metabolic screening. In this work, Chlorella vulgaris was investigated by encapsulating in a simple droplet-based micro-array device at different light intensities of 20, 80, and 200 µmol/m2/s combined with different nitrate concentrations of 17.6, 8.8, and 4.4 mM. The growth results for C. vulgaris within microfluidic device were compared to the conventional batch culture method. In addition, the effect of combined stress of deficiencies in irradiance and nitrogen availability were studied to illustrate their impact on the metabolic profiling of microalgae. The results showed that the most optimum favorable culturing conditions for Chlorella vulgaris growth within the microfluidic channels were 17.6 mM and 80 µmol/m2/s.

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SummaryThe present study evaluates the genotoxic and cytotoxic effects of the crude water and ethanol extracts of Peganum harmala L. (Zygophyllaceae) on the Vicia faba L. M1 generation. Two types of treatments were carried out in this study. In the first type, the germinated root tips were treated with four dilutions of the water extract and ethanol extract (12.5, 25, 50 and 100%). All concentrations were applied for 3, 6, 12 and 24 h. In the second treatment, soaked V. faba seeds were treated with the same concentrations of the two extracts for 3, 6, 12, and 24 h, and then planted to raise the M1 generation. Root tips were squashed after Feulgen staining, and the prepared slides were analyzed for chromosomal aberrations and mitotic index changes. Significant concentrationdependent increase and duration-dependent decrease of MI were observed with aqueous extracts, while with ethanol extracts, the MI showed concentration-and duration-dependent decrease. The two extracts induced significant (p 0.01) increase in the percentage of nuclear and chromosomal aberrations. Concentration-and duration-dependent increase in the number of branches per plant and decrease in the other studied growth parameters were also recorded for all treatments with the water and ethanol extracts.