Blue rot disease caused by Penicillium expansum is one of the most widespread fungal diseases that affects apples worldwide. This work was to verify the effect of chitosan (2 and 4 g/L) and its nano-form (0.2 and 0.4 g/L) against blue rot disease on apples and their effect on the expression of six defense-related genes as well as fruit quality parameters. Regarding disease incidence, in most cases, chitosan NPs performed better as compared to their raw materials for both artificial and natural infections. The highest efficacy was obtained for chitosan NPs at 0.4 g/L for artificial and natural infection in both 2019 and 2020 seasons. All treatments kept fruit quality parameters regarding firmness, total soluble solids, and titratable acidity for artificial and natural infection in both seasons. As expected, the exogenous application of chitosan NPs and bulk form triggered an increase in the expression levels of six defense-related genes including chitinase, peroxidase, β-1,3-glucanase, Xyloglucan endotransglycosylase (XET), pathogenesis-related protein (PR8), and phenylalanine ammonia lyase-1 (PAL1). Moreover, the highest mRNA quantity of all the studied genes was detected in leaves treated with chitosan NPs at both concentrations compared to other treatments. Chitosan NPs can be considered an eco-friendly and effective approach against blue mold of apples and can be integrated into management programs to maintain postharvest quality and extend the shelf life of fruits.

The limited rabbit resources in Egypt are threatened by the danger of extinction, whereas genetic diversity studies of native breeds could play a vital role in conservation and improvement of these breeds. In this study, 3 native rabbit breeds: Gabali (G), Baladi Red (BR) and Baladi Black (BB), in addition to New Zealand White (NZW), were genotyped using 12 microsatellite markers. All the typed microsatellites were polymorphic by average number of alleles 5.25 per locus. Observed and expected heterozygosity per locus averaged 0.62 and 0.68, respectively. The average polymorphic information content was 0.71 and the highest polymorphic information content was recorded in locus SOL33 by 0.85. All the studied loci except SAT7 and SAT2 showed deviation from Hardy-Weinberg equilibrium with significant level. The inbreeding coefficient of the individuals relative to the total population was 0.07. The within-population heterozygote deficit averaged 0.07 and ranged from 0.141 in BR to 0.015 in BB breeds. The highest pairwise differentiation among the populations was recorded between BB and NZW (0.071), while the lowest value was recorded between BR and both of G (0.038) and BB (0.039). The lowest pairwise Nei’s genetic distance was recorded between BR and BB (0.190), while the highest was recorded between NZW and BB breeds (0.409). BR and G populations were clustered together forming an admixed mosaic cluster. BR recorded the highest contribution in the aggregate genetic diversity based on the three prioritisation methods used.

Forty-two bacterial isolates were collected from soft-rotted potato tubers originating from four governorates in Egypt. Their phenotypic and genetic characteristics were studied. The phenotypic identification resulted in grouping the studied isolates into five different species and/or genera including Pectobacterium sp., Bacillus sp., Dickeya sp., Pseudomonas sp. (1), and Pseudomonas sp. (2). The molecular identification of the 10 isolates of them were pathogenic to potato tubers and other hosts. More specific identification of the later 10 isolates, using two specific primers for P. carotovorum subsp. carotovorum (Pcc) and the reference strain PccY46 (Acc. No. KP187511.1), revealed that all these isolates had yielded 220–272-bp DNA fragments identical to the 16S rRNA gene of PccY46. Phylogenetic analysis showed sequence similarity ranging from 87 to 98%, which confirmed the genetic variation among the 10 tested strains of Pcc. The isolates were distributed in four major clusters, each subdivided into a few sub-clusters. In another experiment, two different essential oils (peppermint and clove oils) plus a nano-Cu-based fungicide (Tango®), in comparison to the two different antibiotics and the two copper fungicides, were evaluated for their potential management on the three most severe bacterial isolates (Pcc1, Pcc5, and Pcc10). Results of in vivo experiment showed that clove oil was the most effective, where it caused a reduction of disease severity (0.0%) on potato tubers, 4 days post artificial inoculation.

Chlorella vulgaris species was isolated from Nile River in Qalubia Governorates, Egypt. The highest constant of growth (μ=1.5), and the lower time of reproducing a generation (G=0. 2). The green alga was identified using 18S rRNA gene amplification followed by sequencing the resultant sequence was compared with those available on the NCBI website database through the BLAST bioinformatics tool. The percentage of lipids synthesized was 20 %. In order to increase lipid contents in this green alga was made chemical mutation by EMS. Using three concentrations from EMS (0.1, 0.01 and 0.001) for two hours. The resulted in the treatment of concentration 0.1 decrease total lipid to 16.2 % in by concentration 0.01 almost no change the total lipids were equal with wild strain. By the concentration 0.001 a significant increase in total lipids content as it reached 25% compared with wild strain.