Effect of molybdenum application in pepper (Capsicum annuum L.) under cold stress conditions

Cold stress (low temperature stress) is one of the abiotic stress factors. It causes many morphological and physiological problems in plants. One of the applications to eliminate and alleviate these negative effects is molybdenum application. The aim of this study was to determine the effect of molybdenum application on cold stress in commercial variety Mazamort pepper. In the experiment, control, 25 ppm molybdenum concentration, 72 hours cold stress and 25 ppm molybdenum +72 hours cold stress applications were included. Pots of 2 L were used to grow the plants and the growing medium was a mixture of peat and perlite in a ratio of 2:1 by volume. Climatic chamber conditions were set to 24±1°C during the day and 18±1°C at night with 16/8 h light/dark photoperiodicity for control conditions and 24±1°C during the day and 5±1°C at night with photoperiodicity for cold stress conditions. The experiment was planned according to the random plots factorial design with 3 replications and 6 plants in each replicate. At the end of the study, plant height, stem diameter, number of leaves, plant fresh and dry weight, SPAD, wet basis moisture content, leaf proportional water content and ion leakage parameters were analysed. The highest plant height of Mazamort pepper variety was determined in 25 ppm molybdenum+72 hours cold stress application (44.51 cm). Application of 25 ppm molybdenum was effective in alleviating the negative effect of cold stress on plant stem diameter, plant fresh-dry weight and turgor potential. Moisture content wet basis was lowest in 25 ppm molybdenum +72 hours cold stress application. SPAD value in pepper plants decreased under cold stress conditions. It was observed that 25 ppm molybdenum application was ineffective and the decrease increased under cold stress conditions. Ion leakage in Mazamort pepper variety was highest under 72 hours cold stress and 25 ppm molybdenum +72 hours cold stress conditions. Under cold stress conditions, 25 ppm molybdenum application was ineffective. Molybdenum application under cold stress conditions was found to have positive effects on some parameters in general. In future studies, we believe that the application of different molybdenum concentrations and different cold stress periods will reveal the effects of molybdenum more clearly.