Morphological, Biochemical, and Molecular Characterization of Exotic Brassica Germplasm.

Oilseed rape (Brassica napus L.) is an important oilseed crop. We examined the diversity of germplasm expressed at three distinct levels (i.e., morphological, biochemical, and DNA levels). In this study, 150 B. napus L. accessions with three check varieties were provided by Bioresources Conservation Institute. The germplasm was grown in field conditions for data collection of 15 quantitative and nine qualitative agro-morphological traits. The result indicated that for 15 quantitative agro-morphological traits, the highest coefficient of variation was recorded for plant height and days to flowering initiation. For nine qualitative traits, most of the accessions have a spatulate leaf, brown color seeds, yellow flowers, and erect silique attitude. The best adoptable genetically diverse exotic Brassica germplasms were selected, i.e., accessions 24178, 24881, 24199, 24214, 24242, and 24192. Based on biochemical analysis for high oil content and high oleic acid content, chakwal sarsoon and accession 24192 were selected. For high oleic and linoleic acids, accession 24181 performed best, for low erucic acid accessions 24177 and 24195. Based on molecular (SSR) markers, the top 50 selected genotypes were evaluated with 30 SSR markers. The 47 genotypes with three check varieties were clustered in six major groups; the coefficient of similarity ranged between 0.18 and 1.00. Based on SSR data, the germplasms accession 24178 and Abasin were the most diverse genotypes. These genotypes have the capacity and could be used in future breeding programs. High genetic variations were investigated through the SSR among the studied genotypes of Brassica napus L. The present study also concluded that SSR is a better technique for intraspecific genetic diversity. Other modern techniques should be applied such as SNIP for the investigation of a high level of genetic diversity among crop plants in the future.

Production of Virus-Free Rose Plants using Meristem-Tip Culture and in vitro Thermotherapy.

<b>Background and Objective:</b> Tissue culture and thermotherapy were proved to be suitable in eliminating viruses of many plants. This study was designed in an attempt to produce virus-free Al-Taif rose plants (<i>Rosa damascena</i> Trigintipetala Dieck) through the practical application of the tissue culture approach and thermotherapy. <b>Materials and Methods:</b> Double Antibody Sandwich-Enzyme-Linked Immunosorbent Assay ( DAS-ELISA) and Reverse Transcription-Polymerase Chain Reaction (RT-PCR) techniques were used to detect the presence of <i>Apple mosaic virus</i> (ApMV) and <i>Strawberry latent ringspot virus</i> (SLRV) in rose plant materials collected from Taif, KSA. RT-PCR was more sensitive than DAS-ELISA in detecting the 2 viruses. <b>Results:</b> Three different meristem-tip sterilization methods were compared and results revealed that treatment 3 (T₃: 70% Ethanol for 1.0 min and 15% Clorox (Sodium hypochlorite 5.25%) for 10 min) was the most suitable as 97.78% of cleaned meristem tips survived. Meristem tips with different lengths were thermotherapy-treated for different durations. It was indicated that meristem tips of 0.5 or 1.0 cm and heat-treated at 37^oC for four weeks gave the highest percentage of meristems that were able to differentiate into micro-shoots. <b>Conclusion:</b> RT-PCR detection of ApMV and SLRV revealed that using thermotherapy-treatment, for 4 weeks, of 0.5 cm long meristem tips was successfully applied to eliminate the 2 viruses in 92 and 96% of regenerated plantlets, respectively.

Protective Role of Juniperus phoenicea L. Leaves Extract against Gamma-irradiation-induced Oxidative Stress.

BACKGROUND AND OBJECTIVE: Radiation exposure can cause several harmful effects in biological systems due to free radical production. Several antioxidants have been tested as potential hepatoprotective agents against ionizing radiation as they lower oxidative stress in normal cells induced by Reactive Oxygen Species (ROS). The present study was conducted to evaluate the possible ameliorative effects of Juniperus phoenicea L. MATERIALS AND METHODS: Aqueous leaves extract on different biochemical and histopathological parameters against whole body gamma-irradiation-induced oxidative stress, organ dysfunction and metabolic disturbances in experimental Swiss Albino rats. After a single dose of gamma-radiation (6 Gy), there was a significant reduction in albumin, total protein and globulin levels and a significant increase in the liver enzymes (ALT, AST, ALP and GGT) and lipid profile parameters (cholesterol, triglyceride, HDL-cholesterol and LDL-cholesterol) in gamma-irradiated rats unlike in normal controls. RESULTS: The gamma-irradiated rats pre-treated with J. phoenicea leaf extracts, however, showed a significant increase in albumin, total protein and globulin levels and a significant reduction in liver enzymes and lipid profile parameters as opposed to the untreated ones. The gamma-irradiated rats showed toxic changes in the liver, whereas, the rats pre-treated with J. phoenicea leaves extract demonstrated a protective effect. Additionally, gamma- irradiation caused myocardial degenerative changes, interstitial edema between muscle fibers, necrosis and inflammatory cells infiltration and fibrotic and cellular damages to the heart, but J. phoenicea leaves extract were found to ameliorate the gamma-irradiation-induced changes in the heart. CONCLUSION: The results suggested that treatment with J. phoenicea leaves extract is possibly safe and can ameliorate gamma-irradiation-induced oxidative damage and tissue injury in rats. The leaves of J. phoenicea could serve as a potential source of therapeutic antioxidants.

DNA Fingerprinting of in vitro Micropropagated Pomegranate Genotypes.

BACKGROUND AND OBJECTIVE: Pomegranate is grown for its rich flavour in numerous tropical and subtropical areas, like Egypt and the Kingdom of Saudi Arabia (KSA). Assessing the genetic background of the pomegranate is the key to its expansion through the Middle East, where tissue culture reproduction strategies could be used to solve environmental and economic problems. This study aimed at studying the genetic stability of 2 pomegranate genotypes in vitro micro-propagated in the Kingdom of Saudi Arabia by using the random amplified polymorphic DNA (RAPD) polymerase chain reaction (PCR) and inter simple sequence repeats (ISSR) tools. MATERIALS AND METHODS: The two above mentioned molecular tools were used to evaluate the DNA fingerprints of Taify and Yemeni pomegranate genotypes 12 weeks post in vitro propagation in Taif, Kingdom of Saudi Arabia compared to the mother plant. Shoot tip explants of 4-5 cm long were grown on Murashige and Skoog (MS) medium supplemented by 1.0 mg L-1 NAA, 2.00 mg L-1 IBA and 2 g L-1 activated carbon for 4 weeks for rooting. On 12 weeks DNA extracts were prepared from the acquired plantlets obtained and used as templates for each of RAPD-PCR and ISSR tools. RESULTS: The RAPD-PCR and ISSR assays generated a total of 79-94 and 57-72 DNA fragments, respectively. In case of RAPD-PCR 80 and 90% of the primers used and developed monomorphic fragments of the Yemeni and Taify genotypes, respectively, particularly OPG08 primer for Taify genotype and OPA04 and OPD07 primers for the Yemeni genotype. Regarding ISSR, no DNA polymorphic for the micropropagated clones were recorded compared to the mother plant. CONCLUSION: The ISSR assay's findings indicated the genetic homogeneity between the in vitro micropropagated clones of both pomegranate genotypes and the mother plants.