The effect of molybdenum on the molecular control of cold tolerance in cauliflower (Brassica oleracea var. botrytis) artificial seeds

Molybdenum (Mo) was used to improve the cold tolerance of cauliflower microshoots/artificial seeds. The optimal stage to introduce Mo to the micropropagation system was found to be the microshoots liquid culture stage, since its use within artificial seed capsules or conversion media had negative effects on conversion rate and viability. Mo was found to improve the cold tolerance of both acclimated and non-acclimated microshoots/artificial seeds. The capacity of Mo to up-regulate CBF/DREB1 in cauliflower microshoots was confirmed. Moreover, this study is the first to confirm the ability of this element to upregulate CBF/DREB1 without any low temperature treatment. Mo significantly increased the accumulation of 23 kDa polypeptide when it was used at 15 ppm concentration. However, Mo had a negative effect on the accumulation of dehydrin proteins which suggest that this group of proteins have no significant role in the cold tolerance of cauliflower microshoots. The study could help in improving the understanding of the abiotic stress network in plants and in improving the quality and efficiency of cauliflower artificial seed production systems.