The Effects Of Salt Stress And Exogenous ABA On Growth Of Five Sedum

Sedum are widely used in dry areas and green roofs because of its excellent drought resistance, exploring salt-tolerant species to enhance the green landscape effects of saline soil area is the work of scientific value and practical significance. Five Sedum, Sedum lineare, S. lineare cv.’Jin Ye’, S. sarmentosum, S. emarginatum and S. aizoon have been evaluated for their responses to salinity and exogenous ABA in terms of some physiological and biochemical indexes.Using two-factor randomized block design,5Sedum species were treated with four salt concentrations (0、6‰,12‰,24‰) and two ABA concentrations (0,0.1mmol/L), turf quality、 relative water content、 chlorophyll content、 electrolyte leakage、 malondialdehyde content、 SOD、 POD、 CAT were determined0、14、28、42d after treatment, using root growth monitoring system to scan the root growth conditions at0、30、60d after treatment. The results showed that:1) Salt stress significantly inhibited Sedum growth, with increasing salt concentration, the inhibition of shoot and root growth was significantly enhanced, which can be observed in the decreased plant turf quality, root growth rate, relative water content.2) Salt stress have significant impact on the physiological and biochemical indicators of five Sedum, and different concentration of salt treatment showed significant difference. Under salt stress, superoxide dismutase (SOD), peroxidase (POD) firstly raised and then decreased, catalase (CAT) had elevated, the content of MDA and membrane preability increased.3) The salt-tolerant ability of these five Sedum species decreased in order of:S. emarginatum> S. lineare’Jin Ye’> Sedum lineare> S. sarmentosum> S. aizoon.4) Under salt stress, the growth of Sedum seedlings was inhibited. While exogenous ABA have a significant alleviation role in salt stress, promoting root elongation, significantly increased chlorophyll content, reduced electrolyte leakage, and improved the activity of SOD, so exogenous ABA improved the salt-tolerance of these five Sedum on a certain extent.