BackgroundWheat is considered the most important cereal crop all over the world. The wheat weevil Sitophilus granarius is a serious insect pests in much of the wheat growing area worldwide and is responsible for significant loss of yield. Avidin proteins has been proposed to function as plant defense agents against insect pests.ResultsA synthetic avidin gene was introduced into spring wheat (Triticum aestivum L.) cv. Giza 168 using a biolistic bombardment protocol. The presence and expression of the transgene in six selected T0 transgenic wheat lines were confirmed at the molecular level. Accumulation of avidin protein was detected in transgenic plants compared to non-transgenic plants. Avidin transgene was stably integrated, transcribed and translated as indicated by Southern blot, ELISA, and dot blot analyses, with a high level of expression in transgenic wheat seeds. However, no expression was detected in untransformed wheat seeds. Functional integrity of avidin was confirmed by insect bioassay. The results of bioassay using transgenic wheat plants challenged with wheat weevil revealed 100 % mortality of the insects reared on transgenic plants after 21 days.ConclusionTransgenic wheat plants had improved resistance to Sitophilus granarius.

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The present study has been carried out to investigate the possible mutagenic effects of the synthetic food color tartrazine on mitosis, deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) contents of Allium cepa roots and protein banding pattern of A. cepa seeds. The obtained results indicated that the synthetic food color tartrazine (E102) had the ability to cause different mitotic changes varying from reduction in mitotic index to the production of a large number of mitotic abnormalities. These changes appeared in varying degrees depending on the applied concentration and duration of treatment. The types of abnormalities produced were laggards, bridges, stickiness, C-metaphase and disturbed phases as well as micronuclei. The amounts of both DNA and RNA were generally decreased with increasing of most concentrations and time of treatment. At electrophoretic level, E102 induced alternations in the protein banding pattern of A. cepa seeds as compared with the control. These alternations were expressed as disappearance of some characteristic bands, appearance of new bands, and changes in band intensities. The administration of vitamin C was found to be very helpful in minimizing the toxic effects induced by E102.

In the present study, sodium azide (SA) toxicity and the anti-mutagenic effects of different algal extracts at 0.1% and 0.2% concentrations were studied on the mitotic index (MI), chromosomal and nuclear aberrations using Allium cepa L. root assay. Moreover, phytochemical screening of photosynthetic pigments, antioxidants compounds, total antioxidant, DPPH scavenging activity, polysaccharides, and phenolic contents were done for two red seaweeds (Laurencia obtusa (Hudson) Lamouroux and Polysiphonia morrowii Harvey) and for one brown seaweed (Dictyopteris delicatula Lamouroux). Treatment with 300 μg/ml sodium azide (SA) induced the highest number of aberrations in A. cepa root. A highly significant decrease in the MI appeared after treatment with SA, whereas its value increased following different algal extracts treatments. The highest anti-mutagenic inhibition activity of Dictyopteris delicatula added at 0.2% concentration was 72.96%, 69.84%, 56.89% and 43.59% with the algal polyphenol, polysaccharide, aqueous and methanol extract treatments, respectively. The different algal extracts minimized the genotoxicity and exhibited anti-mutagenic potential against SA in a dose-dependent manner. Phytochemical studies showed that Dictyopteris delicatula contained the highest total phenol, chlorophyll-a and carotenoid quantity. Moreover it exhibited the highest total antioxidant and DPPH scavenging activities. Total polysaccharides and the weight percentage of sulphated polysaccharides were relatively higher in Polysiphonia morrowii followed by Laurencia obtusa. Hydroquinone and bromophenol were detected only in the studied brown and red seaweeds, respectively. Polysiphonia morrowii and Laurencia obtusa contained the highest quantity of galactose, rhmnose and xylose, while Dictyopteris delicatula contained fucose and mannitol as main monosaccharide units. In conclusion, the studied seaweeds may be considered as rich sources of natural antioxidants. Meanwhile the investigated different algal extracts can minimize the genotoxicity in a dose-dependent manner and exhibit anti-mutagenic potential against the mutagenic substance sodium azide.

L ENTIL (Lens culinaris Medikus) is an important seed legume crop cultivated worldwide as human food. Little is known about the molecular structure of the Egyptian lentil. Intervarietal variation and cultivar identification are crucial for breeding and gene bank conservation of this plant worldwide. The SDS-PAGE and SRAP-PCR techniques were used to detect some biochemical and molecular markers of six Egyptian lentil genotypes (Sinai 1, Line 9, Giza 1, Giza 4, Giza 51 and Giza 370). The genetic distance between cultivars was also estimated from banding patterns. The results of SDS-PAGE revealed a total of 21 bands with molecular weight ranging from about to 6-102 KD. The maximum number of bands (14) appeared in Giza 4, while the minimum number of bands (10) appeared in Giza 1. Electrophoresis analysis among six lentil cultivars showed 80.95% polymorphism, while DNA variations were explored using ten combinations of SRAP markers. SRAP analysis among six lentil cultivars showed 61.54% polymorphism. The highest similarity index (0.869) was found between Giza 51and Giza 370. The lowest similarity index (0.603) was found between Giza 1 and Giza 4. The markers used in this study created polymorphic bands among the different cultivars that can be utilized as molecular markers for their differentiation. The obtained data indicated that SRAP and SDS-PAGE systems can efficiently identify and differentiate between the selected cultivars. Also these results, enhancing the available knowledge of lentil genetic resources in Egypt, may contribute to their conservation and utilization in breeding programs.