Effects Of Exogenous Calcium And EGTA On Seed Germination And Physiological Characteristics Of Pepper (Capsicum Annum L.) Seedlings Under Salt Stress

In order to study the effects of different types of salt stress on pepper (Capsicum annum L.) seedlings and germination, and to research how Ca²⁺ can relax the salt injury, this article used Longjiao 2 as the basic testing material. Used two kinds of NaCl concentration to treat the material and after the treatment add Ca(NO3)2 solution and EGTA, The findings are as follows:1. The effects of NaCl stress on germination of pepper(Capsicum annum L.)seeds were extremely distinct influence, with the increase of NaCl concentration, the inhibition on germination increased significantly. The germination rate,germination energy and the length of seedlings were all descend, and the relatively conductance rate increased. Under NaCl stress, the appropriate exogenous Ca²⁺ can mitigate NaCl stress in some degree. And the conductance rate was less than comparison, meanwhile reduced the germination rate and the length of seedlings.2. Has studied the different concentration of NaCl and under the stress condition added extraneous source Ca²⁺ to influence the hot pepper seedlings. The result indicated that: All has certain suppression under the NaCl stress in hot pepper seedling's growth quantity, under the concentration of 90mmol·L-1 NaCl, the exogenous calcium ion effect is not obvious, but under salt stress of 150mmol·L-1 NaCl, the calcium ion can alleviate salt injury significantly. Low concentration Ca²⁺ has enhanced the hot pepper's root activity under the stress. Compares with the salty stress on hot pepper seedling, Ca²⁺ is not good to the chlorophyll a, but may increase the contents of chlorophyll b. In these three targets, the EGTA processing displays the intense inhibitory action, it means that the lacks of the calcium ion to produce more injury in pepper's seedlings.3. As tries the material of pepper Longjiao 2, studied it to join extraneous source Ca²⁺ and the EGTA processing under the different stress, finally indicated: The soluble sugar content under two kinds of salt stress, the performance is the rise, its content dropped after adds the calcium, the processing of adds EGTA related with the salinity concentration, the different salinity performance is inconsistent. The soluble protein content all drops along with the time goes by, the processing of adds calcium to be high under the high salinity density content, two kinds of density salt stress used with EGTA processing, the soluble protein content all must be higher than any processing. The proline content all has increased under salty processing, although adds calcium processing is higher than the comparison content, but the overall must be lower than the sole salinity processing content, and the EGTA processing response is not obvious. Added the Ca²⁺ processing to reduce the MDA content in hot pepper leaves under salt stress , about the injury rate ,it is lower than CK and the sole salty stress in the Ca²⁺ processing, but EGTA processing's injury rate compared to comparison and sole salty processing are all remarkable. 4. As tries the material of the pepper Longjiao 2, studied the effects on membrane-lipid peroxidation and resistant-oxidation enzyme activities of pepper seedlings under the different salinity density stress, finally indicated: The SOD activities drops because of the salinity stress, the time and the density more increase, then drops obviously, after use exogenous Ca²⁺ can reduce the drop of SOD effects. The POD and CAT activities performance quite is similar, added Ca²⁺ after the salty stress, the activities to be higher than the enzyme activities under the sole salty stress, but processes completely compared to the comparison all has dropped; The APX activeness all has the drop under the salty stress, after use exogenous Ca²⁺ is obvious to the highly concentrated salinity function, but it was still unable to surmount the comparison APX activeness. Four kinds of enzyme responses are consistent under the EGTA processing; all reduced the enzyme activeness, weakened the Ca²⁺'s function.