Comparative Study On Salt Tolerance Of Two Jerusalem Artichoke Cultivars

Our vast coastal areas have a large area of saline soil,planting salt-tolerant crops in saline area can effectively utilize the growing tension in the land resources,the study of salt-tolerant crops Jerusalem artichoke can help yield higher and breeding adaptable varieties.In this thesis,we choose two Jerusalem artichoke varieties,they are Nanyu No.1?NY-1?and Henan province Jerusalem artichoke?M1?as test materials.Using hydroponic test in greenhouse trials to different concentrations of NaCl?0,100,200mmolL-1?for processing.Observed and studied the response of these two varieties of Jerusalem artichoke for stress,compare and analyze the morphology,biomass,activity of antioxidant enzyme,to explore the stress ability and physiological changes of Jerusalem artichoke under NaCl stress,then compare the salt tolerance of them.The main result were listed as follows:1.The two species have consistent response to salt stress.The inhibition of the growth increased with the increasing of NaCl concentration,at the time of 15d,the growth inhibition is significant when two treatments compared to the control.The growth inhibition under low concentrations of salt?100 mmol L-1?stress was significantly lower than the high concentrations of salt?200 mmolL-1?stress.The fresh weight dry weight and moisture content of the two varieties Jerusalem artichoke decrease with NaCl concentrations increased,and this trend will be more significant with the time last long.2.The chlorophyll content in two varieties of Jerusalem artichoke have consistent trends under the salt stress.At the time of 15d under low concentrations of salt stress,the chlorophyll content of NY-1 increased compared with the same period in control,but with the extension of the time the chlorophyll content decreased significantly,under high salt treatment,the chlorophyll content has always been decreasing.The chlorophyll a and b content of M1 at 15d in each treatment did not change significantly,at 30d and 45d in each treatment were significantly different.3.SOD,POD,CAT in the leaves of two varieties of Jerusalem artichoke under low salt stress showed high activity.SOD and POD in the leaves of NY-1 under high concentrations of salt stress compared with the same period of control increased at the first and then decreased,while CAT content was gradually decreased.POD and CAT activity in the leaves of Ml reached the highest level on Day 15 under high concentrations of salt stress,then decreased with the time extension,on Day 30 and Day 45 the activity become stable.4.Salt stress has little effect on the content of soluble sugar?SS?in the root,the high salt concentration can reduse the SS in stems and leaves,while at low concentrations will promote content of SS in stems.The two species have consistent tend of soluble protein?SP?in leaves,on Day 15 the content of SP was significant positive correlation with the concentration of salt,with the time extend,the high salt concentration let the SP content decrease to the same level with the same period of control.5.The Mg²⁺ content in root,stem,leaf of two varieties of Jerusalem artichoke were significantly lower than CK in a long time at high concentrations of salt stress,but low concentration of salt stress causes NY-1 leaves and stems Mg²⁺ content increased,M1 leaf and root Mg²⁺ content increase.Low concentrations of salt stress can increase the two Ca²⁺ content in stem of two varieties in short time,but prolonged stress with high concentrations of salt can reduse the Ca²⁺ content in different parts of two varieties.High concentrations of salt stress can increase the content of Na⁺ in different parts of two varieties.The content of K⁺ show as downward tend and under low concentrations of salt stress was not significantly different,the high concentration for a long time salt stress significantly different.6.Compared with NY-1,the change range of chlorophyll content of M1 under salt stress is smaller,the SOD,POD,CAT activity and soluble sugar content is higher and the MDA and Na+ content is lower.M1 salt above differences can be judged better than NY-1.According to the above differences,we find M1 is better than NY-1 at salt tolerance.