Factors affecting resistance of winter rapeseed (Brassica napus L.) shoots to cold stress in vitro

Abstract

Research was carried out at the Institute of Biology and Plant Biotechnology of Aleksandras Stulginskis University and at the Laboratory of Agrobiotechnology of the Joint Research Centre. The effect of cultivar, acclimation duration and exogenous L-glutamic acid on the changes of proline level and electrolyte leakage in shoots of winter rapeseed was evaluated. The shoots were cultivated in the MS medium supplemented with 0, 1, 2, 3 and 4.0 mM l–1 L-glutamic acid. The resistance of shoots to cold stress (at –8 °C for 24 h) was estimated by an electrolyte leakage test. It was found that the exogenous L-glutamic acid stimulates the synthesis of endogenous proline in non-acclimated as well as acclimated shoots. The highest increasing in cold resistance of winter rapeseed shoots has been obtained under the synergic effect of L-glutamic acid and acclimation. The shoots of cultivar ‘SY Kolumb’ were most cold-resistant independent of the acclimation duration and the concentration of L-glutamic acid in the medium.