Study On The Enhancement Of Disease、Salt And Drought Tolerance Of Lotus Corniculatus L. By Transgene HhERF

Drought and soil salinization and plant diseases has been becoming the most important factorsleading to yield loss of crops. Although various attempts have been made to the solution to droughtand soil salinization, no notable results had been achieved. The best measures are thought tocultivate drought and salt–tolerant cultivars of crops in such area. Attempts to breeding drought andsalt–tolerant cultivars have been made by introducing various drought and salt–tolerant foreigngenes into crop cultivars via molecular biology technology over the past years. In this paper, weanalysed HhERF cloned from Halimodendron halodendron.The HhERF gene was transferred intothe Lotus corniculatus to expect to improve drought resistance and salt endurance and diseaseresistance.Major results obtained are as follows:1、The plant expression vectors of PMI-HhERF was verified by PCR and Enzyme validation. Usingbgrobacterium-mediated transformation,96resistant plant were obtained by PhosphomannoseIsomerase as a Selection Marker.23transgenic L. corniculatus plants were obtained by PCRvalidation,The percent conversion is24%. the results of PCR，RT-PCR showed that theHhERFgene were obtained from the plant genome, the results of PCR-Southern and Southernshowed that the HhERFgene was expressed in protein expression levels. Using cutting propagationsystem, transgenic L. corniculatus plants were Grown in ShunYi BeiJing.2、Build cutting propagation system of Lotus corniculatus L.Sawdust:coir pith:vermiculite:substrateis2:1:0:0or2:2:0:0which is the best approach using L8（27）orthogonal test.3、Analysis the drought-tolerant functional of HhERF gene.Determination of physiological andbiochemical Indexes of Leo after drought stress of0d、3d、6d、9d、12d and rewatering3d、6d. Thetest results show that:(1) Under drought stress, RWC、SOD、 POD is higher in transgenic plant.MDA is higher in wide type.The Chl in the two group has no significant difference. Results showthat transgenic plant is better than wide type in tolerance to drought stress.(2) partial rehabilitationof RWC、Chl、MDA、SOD、POD after two times rewatering prove that the damage of cellmembrane is partial rehabilitation.drought4、Analysis the salt-tolerant functional of HhERF gene. Determination of physiological andbiochemical Indexes of Leo after salt stress of0、50、100、150、200、250mM NaCl. The testresults show that:(1) The effects of salt stress is not obvious to plant height of transgenic plant isnot obvious.(2) When salt concentration was higher than150mM, RWC、Chl is higher in transgenicplant. MDA is higher in wide type. Results show that transgenic plant is better than wide type intolerance to salt stress. 5、Analysis the disease-resistant functional of HhERF gene. Determination of physiological andbiochemical Indexes、disease incidence、DI of Leo after the inoculation of Fusarium oxysporumof2d、4d、6d、8d、10d. The test results show that:(1) transgenic plant and wide type areoccurrence of plant diseases at6d.The disease incidence、DI is higher in transgenic plant.(2) SOD、POD is higher in transgenic plant. MDA is higher in wide type.The RWC and soluble sugarin the two group has no significant difference. Results show that transgenic plant is better than widetype in tolerance to plant disease.