Nalan Yildirim

The protective role of zinc and calcium in Vicia faba seedlings subjected to cadmium stress

The aim of the present study was to evidence the possible antagonistic effect of Zinc (Zn2+) and Calcium (Ca2+) against cadmium (Cd2+)-induced DNA damage by using random amplification of polymorphic DNA (RAPD) and metabolic activities in Vicia faba. The results showed that all doses of Cd2+ (10 -3 M, 10-5 M) caused an increase in polymorphism value and a decrease in genomic template stability (GTS %). In addition, when 10 -4-10-6 M Ca2+, 10-6 M Zn2+ were added together with 10-3 M, 10-4 M, 10-5 M of Cd2+, polymorphism value decreased besides GTS, total protein and chlorophyll content increased. Results suggested that Zn2+ and Ca2+ have an antagonistic effect against Cd2+. The order of the antagonisms of Ca2+, Zn2+ against Cd2+ toxicity was Ca2+ > Zn2+. Especially, the degree of antagonistic effect of Zn2+ against Cd2+ is probably related to its concentration ratio.

Determination of protective role of selenium against aflatoxin B1-induced DNA damage

Selenium is an essential mineral for a healthy life. Appropriate doses of it may undertake a protective role in the organism. In this study, the protective role of selenium (Se4+) against aflatoxin B1 (AFB1)-induced DNA damage was determined using random amplified polymorphic DNA on two plants including Vicia faba and Zea mays. It was observed that the concentrations of 0.1, 0.2 and 0.4 ppm of AFB1 have increased polymorphism value, total chlorophyll inhibition rate (IRc, %) and total protein IR (IRp, %). Unlike protein, chlorophyll contents and genomic template stability were decreased. With the addition of different concentrations (0.8 and 80 ppm) of Se4+ to the treated samples with AFB1, the values return to normal. An 800-ppm concentration of Se4+, on the contrary, could not inhibit the toxicity of AFB1 but caused an increase in toxicity level of AFB1/enhanced the toxicity level of AFB1. Results suggested that Se4+ has an antagonistic effect against AFB1 toxicity and that the degree of antagonistic effect of Se4+ against AFB1 was related to its concentration.

Genetic Diversity in Grapevine Germplasm Resources in the Coruh Valley Revealed by RAPD Markers

Random amplified polymorphic DNA analysis was carried out in 35 autochthonous table grapevine cultivars grown in Coruh valley. Fifty-five oligonucleotide primers were screened on cultivars, and among them, 12 primers showed clear polymorphic patterns. PCR amplification with 12 primers generated a total of 157 polymorphic bands. There was genetic variation among the cultivars with values of genetic diversity ranging from 0.19 to 0.72 using the Jaccard coefficient. UPGMA analysis of the distance matrix resulted in a dendrogram with two main clusters. The first cluster included 28 cultivars and the second 7 cultivars. The greatest genetic similarity was observed between cultivars Gah and Kolik, while the greatest dissimilarity was observed between cultivars Gah and Siyah Kus Uzumu. The dendrogram revealed that the cultivars present in Coruh valley can be distinguished to a relatively high degree.