Determination of the effects of different boron doses on the salinity stress tolerance of fox grape (Vitis labrusca L.) in vitro conditions

This study was conducted in the tissue culture laboratory of the Department of Horticulture at Ordu University, Faculty of Agriculture, during the 2023 vegetation season. Micro cuttings derived from shoots of Balıkçı Siyahı grape type (Vitis labrusca L.) were used as explant. The explants underwent surface sterilization and were cultured in Murashige-Skoog (MS) medium containing 1 mg/l Benzyladenine (BA) to induce shoot formation. The shoots, grown in the medium supplemented with BA, were then transferred to MS medium supplemented with 2 mg/l Indole-3-butyric acid (IBA) for rooting. After rooting, the plantlets were transferred to MS medium containing four different concentrations of boron (0, 0.5, 1, 2 mM, H3BO3 form), three different concentrations of salt (NaCl) (0, 100, 200 mM) and 2 mg/l IBA to create salinity stress and evaluate the effectiveness of boron under these conditions. Several parameters were evaluated in the study, including plant viability (%), shoot fresh weight (g), shoot dry weight (g), shoot length (cm), number of leaves per shoot (n), chlorophyll content (SPAD), damage degree (0-3 scale), shoot tolerance rate (STR), leaf turgor weight (g), ion flow (%), cell membrane damage rate (CMDR, %), and explant relative water content (%). When the results were examined, it was found that the degree of damage, ion flux, and cell membrane damage rate increased with the increase in salt doses. The most pronounced negative effect was observed in the plant subjected to 200 mM salt application, significantly reducing growth and development. However, it was determined that the plant exhibited higher resilience against 100 mM salt in certain parameters. In the overall evaluation of boron effectiveness under salt stress, boron doses of 0.5 mM and 1 mM were identified to have a mitigating effect on the negative impacts caused by salt stress. Based on the findings, it was concluded that boron applications under saline conditions could assist grapevines in coping with the harmful effects of salinity.