Physiological Response To The Six Species Of Rosa Plants In Xinjiang To Drought Stress And Their Drought Resistance

In this research we took the six species of Rosa plants as the test materials.Using pot and water controlling simulated natural drought method and the treatment of the rehydration after the drought stress,through continuous 15 d the drought stress.Observation of the six plants and for drought-resistant physiology indexes determined.The comprehensive evaluation of drought resistance was also conducted using subordinate function value method.In order to screening of excellent drought resistance genes germplasm resources.The results showed that:(1)In the process of drought stress,the Rosa xanthina Lindl.,Rosa webbiana Wall.,Rosa platyacantha Schrenk,Rosa albertii Rgl.RWC content first decreased and then increased,the Rosa acicularis Lindl.RWC content first increased and then decreased.In 5days drought stress,the Rosa platyacantha Schrenk reaches the minimum,and the reduction quantity reached a maximum.Comparing CK decline 39.2%.Water saturation of change and the relative water content change instead rising trend.The Rosa albertii Rgl.reduction quantity reached a maximum ΔRWD 2.2%.Show that the Rosa albertii Rgl.have strong ability of water.(2)The six plants,chlorophyll a and chlorophyll b content first increased and then decreased,comparing CK decline,chlorophyll a and chlorophyll b content reaches the minimum in drought stress at 15 days,but on the whole chlorophyll b Change smaller than chlorophyll a.(3)The soluble protein content of Rosa xanthina Lindl.,Rosa webbiana Wall.and Rosa platyacantha Schrenk first increased,then decreased and last increased.Rosa albertii Rgl.,Rosa acicularis Lindl and Rosa laxa Retz.The soluble protein content first decreased and then increased,which,the Rosa albertii Rgl.increased maximum at 15 days,comparing CK decline 6.65mg/g.In the process of drought stress,all of the six Rosa plants accumulation of proline,increased maximum at 15 days,which,Rosa platyacantha Schrenk increased maximum at 15 days,comparing CK decline 475.32mg/g.(4)With the passage of drought stress time,Rosa webbiana Wall.,Rosa albertii Rgl.,Rosa platyacantha Schrenk,Rosa laxa Retz.,the activity of SOD first increased,then decreased,last increased.The Rosa xanthina Lindl.and Rosa acicularis Lindl.first decreased and then increased.Which,Rosa xanthina Lindl.changed most markedly with obvious at 15 days,comparing CK decline 44.3%.Rosa webbiana Wall.and Rosa acicularis Lindl.,the activity of SOD no obvious difference.(5)In the process of drought stress,the six plants of MDA content first increased and then decreased.Which,Rosa webbiana Wall.reaches the maximum,and the reduction quantity reached a maximum at 5days.Comparing CK decline 24%.Shows that the membrane damage is the most serious.(6)With the drought stress aggravate,the six plants leaf morphology all present: leaf color loss green,leaves shrivel wilting ect symptoms.After rewatering,the growth vigor of six plants were recovered gradually,have new branches and leaves.The plants all return to in normal water level.Show that the Rosa plants growth vigor reversible and have strong drought-resistant ability.At drought-resistant rescission the plants growth vigor reversible in a snap.Use the average subordinative function method to sum to the combating drought correlation each target summation,it is concluded that the drought resistance plants from strongest to the weakest were as order: Rosa platyacantha Schrenk>Rosa laxa Retz.> Rosa webbiana Wall.> Rosa acicularis Lindl.> Rosa albertii Rgl.> Rosa xanthina Lindl.