Effects of low temperature and drought on the physiological and growth changes in oil palm seedlings

Water deficiency and low temperature are two important ecological factors which affect the distribution and cultivation of oil palm. To find out how oil palm adapts to the environmental conditions, the dynamics of a series of important physiological components derived from the leaves of potted oil palm seedlings under drought stress (DS) (water with holding) and low temperature stress (LTS) (10°C) were studied. The results showed that low temperature and water stress inhibited the growth of oil palm seedlings. The relative conductivity, injury index, malondialdehyde (MDA) and proline content in the leaves increased to different degrees with the extension of low temperature and drought stress. Superoxide dismutase (SOD) and peroxidase (POD) activities increased and then decreased gradually with the duration of treatment time. The variations of the earlier mentioned parameters except proline content under low temperature stress were greater than that under drought stress. Thus, oil palm possibly showed different response mechanisms under low temperature and drought stress by mediations of these substances, in order to increase plant defense capability. These data provided the information that was utilized to initiate the breeding programme used to improve drought and cold tolerance in oil palm.   Key words: Oil palm, drought stress, low temperature stress, physiological characteristics.