Sema Alikamanoglu

EFFECT OF MAGNETIC FIELD AND GAMMA RADIATION ON PAULOWINIA TOMENTOSA TISSUE CULTURE

ABSTRACT In this study, the in vitro tissue culture of the Paulownia tomentosa plant was established and a magnetic field which has 2.9–4.8mT flux density was applied to the culture at a velocity of 1m/s for 19.8 seconds. Additionally, gamma radiation of 10 and 25 Gy was applied as combined to the magnetic field. It was observed that magnetic field increased the capability of regeneration of Paulownia tomentosa cultures and supported the regeneration in a short time in comparison with the control group and applied radiation dose and decreased regeneration capability were re-supported when combined with magnetic field. It was found that magnetic field has a positive effect on plant fresh weight, leaf number and chlorophyll amount on the 28th day of established cultures of Ptomentosa node explants and the negative effects on these parameters by radiation, when magnetic field and gamma radiation applied together, these parameters changed and aroused depending on the radiation doses.

Analysis of drought-tolerant sugar beet (Beta vulgaris L.) mutants induced with gamma radiation using SDS-PAGE and ISSR markers.

Drought is one of the major environmental stresses which greatly affect the plant growth and productivity. In the present study, various doses (0-75Gy) of gamma rays were applied to investigate the effect of radiation on shoot tip explants. It was observed that the regeneration rates and plant fresh weights decreased significantly with an increase in radiation dose. The optimal irradiation doses for mutation induction were determined at 15 and 20Gy. Afterwards, the induction of somatic mutation in sugar beet (Beta vulgaris L.) was investigated by irradiation of shoot tips with 15 and 20Gy gamma rays. Irradiated shoot tips were sub-cultured and M(1)V(1)-M(1)V(3) generations were obtained. Mutants tolerant to drought stress were selected on MS medium, supplemented with 10 and 20gl(-1) PEG6000. Of the M(1)V(3) plantlets, drought-tolerant mutants were selected. Leaf soluble proteins obtained from the control and drought-tolerant mutants were analyzed by SDS-PAGE. A total of 22 protein bands were determined and 2 of them were observed to be drought-tolerant mutants except the control. Polymorphism was also detected among the control and drought-tolerant mutants by DNA fingerprinting using ISSR markers. A total of 106 PCR fragments were amplified with 19 ISSR primers and 91 of them were polymorphic. The dendrograms were separated into two main clusters. First cluster included M8 mutant plant, which was applied 20Gy gamma radiation and regenerated on selective culture media containing 10gl(-1) PEG6000 concentration, and the second cluster was further divided into five sub-clusters.