Stress induced by soil contamination with heavy metals and their effects on some biomarkers and DNA damage in maize plants at the vicinity of Ferronikel smelter in Drenas, Kosovo.

The Ferronikel smelter in Drenas is one of the main industrial areas in the Kosovo and pollution by heavy metals causes serious threat for all living organisms on this area. The objective of this study was to determine the concentration of some heavy metals (Fe, Cu, Mn, Cr, Cd, Ni and Pb) in agricultural soils and in maize plants, and their potential toxic effects on this plant through some sensitive biochemical and molecular markers. Maize seedlings growth in nine soil samples from different locations of this area. The highest concentrations of heavy metals in soils and maize leaves were conducted close to the Ferronikel smelter, and in some locations, the nickel and chromium concertation in soils exceeded 800 mg kg-1. A significant effects of heavy metals induced toxicity resulted in the, build-up aminolevulinic acid and reduced activity of δ-aminolevulinic acid dehydratase, and chlorophyll content in the maize leaves. In general, maize seedlings growth in polluted locations showed an increase in nuclear DNA content and in G2M phase. We concluded that locations close to the smelter are affected by soil heavy metals pollution and these biochemical and molecular analysis would be a powerful ecotoxicological tool in biomonitoring of heavy metal pollution.

Cryopreservation of shoot apices and callus cultures of globe artichoke using vitrification method.

BACKGROUND: Cryogenic cooling became a crucial tool for the storage of heterozygous plants such as globe artichoke. This study was carried out to optimize a reliable method for in vitro cryopreservation of shoot apices and callus cultures of globe artichoke using dimethylsulfoxide (DMSO) and Plant Vitrification Solutions 2 (PVS2) as cryoprotectant solutions. Shoot apices were exposed to DMSO or PVS2 for 20, 40, 60, and 80 min prior to plunge in liquid nitrogen (LN). RESULTS: It was found that using PVS2 as a cryoprotectant in cryopreservation of shoot apices of globe artichoke was more effective compared with using of DMSO alone. Among the exposure time tested, 60 min gave the best results of survival. The highest survival (60%), regeneration (56%), and proliferated shootlets (4.30) were obtained after cryoprotection with PVS2 for 60 min. Regarding callus cultures, the maximum values of fresh weights and subsequently growth value of recovered callus were registered with 40 min followed by 60 min exposure time. Related to the type of the tested cryoprotectants, the best survival and growth parameters of the cryopreserved callus cultures were obtained with PVS2 treatments. Treatment with PVS2 for 40 min registered the highest survival observations of cryopreserved callus. Also, the maximum values of fresh weight (1.30 g) and growth value (4.20) were obtained with 40 min exposure time. Microscopy analysis presented as cell morphology revealed that the treatment of PVS2 40% was the optimum for cell growth of cryopreserved callus of globe artichoke. CONCLUSION: The results demonstrated that using PVS2 as a cryoprotectant in cryopreservation of shoot apices and callus cultures of globe artichoke was more effective compared with DMSO.

Micropropagation and in vitro conservation of the rare and threatened plants Ramonda serbica and Ramonda nathaliae.

Ramonda serbica and Ramonda nathaliae are rare and endemo relict plant species from Balkan Peninsula. An efficient micro propagation and in vitro conservation method via direct and indirect organogenesis from seed and leaf explants, respectively, was established in this study. The seed of both Ramonda species were collected from different populations in Kosovo, and were germinated in nutrient media JG-B without any phytohormone. The highest number of shoots and multiplication rate was observed on JG-B medium supplemented with BAP and IAA (0.5 mg l(-1) each), whereas the highest number of leaves per plantlets was found on WPM and RA medium supplemented with BAP and IAA (0.1 mg l(-1) each). During this stage of micro propagation some significant differences were observed in plantlets from different populations. The indirect organogenesis from parts of leaves of natural plants was not successful due to unavailability of established protocol for disinfections of the plant material. On other hand, parts of leaves from micro propagated plantlets, cultured on MS medium supplemented with different ratio of BAP and NAA, resulted in the highest efficiency for shoot regeneration. In vitro conservation of micro propagated plants at the lower temperature (4 °C) had a significantly positive effect for storage of more than 12 months.