Effect of low temperature on the synthesis of N-containing compounds in inbred maize lines with varying degrees of cold tolerance

The paper reports on the effect of low temperature on the synthesis of a nu mber of N-containing compounds (putrescine, agmatine, proline and glycine-b etaine) in five inbred maize lines with different degrees of cold tolerance (F7 cmsC, F 564, Co 158 W 153 R and Mo 17). The compounds listed above are regarded as stress markers on the basis of their response to abiotic stres s factors. The aim of the experiments was to obtain a better understanding of the role of these compounds in maize cold tolerance. The results indicat e that changes of various magnitudes occur in the quantities of putrescine, agmatine and proline as the result of cold treatment. The quantitative cha nges are correlated with the cold tolerance of the given inbred maize line. The alternative pathway of polyamine biosynthesis, which functions chiefly in higher plants, probably plays a substantial role in the development of the defence mechanism against low temperature.