Identification Of Drought Tolerance And Expression Analysis Of Related Genes In Seedlings Of Medicago Falcata

In this experiment,Wild Medicago falcata of Xinjiang was used as a material,and mannitol and PEG-6000 were used for drought stress treatment.The seedling germination of Alfalfa under drought stress and the effect of drought stress on the morphology and physiological index of Alfalfa were studied.Drought-resistance sensitive spots and transcriptome sequencing results were used to screen plants for differentially expressed genes under PEG-6000 stress.The related genes were verified by q PCR to identify and utilize the methods and resources for the identification,utilization,protection and drought resistance of alfalfa resources.Identification provides a certain theoretical basis and technical support,and lays the foundation for the development of genetic breeding of drought tolerance.The main results were as follows:(1)The seed germination rate of alfalfa in 1/2MS medium was the highest,reaching more than 85%under mannitol stress treatment.the longest root length was 6.14 cm and the fresh weight was 0.063 g.With the increase of alcohol concentration,the seed germination rate,root length and fresh weight all showed a gradual decline.(2)40 days old plants of alfalfa were treated with 0,10%,20%,30% and 40% PEG-6000,and 30%PEG-6000 was used as a sensitive point for 60 minutes.The SOD,POD,CAT activity,electrical conductivity and soluble sugar content in roots and leaves of alfalfa increased under drought stress compared with the control.The above physiological indexes were lower than the stress treatment after 60 minutes of rewatering treatment.SOD activity,electrical conductivity and soluble sugar content were higher than those in leaves.POD and CAT activities in leaves were higher than those in roots.(3)Using transcriptome sequencing technology,10 genes that may be associated with drought resistance were screened.Actin and UBL-2a genes were selected as internal controls for q PCR validation.The results showed that the expression trends of 9 genes out of 10 genes were consistent.The transcriptome arrays are consistent and demonstrate that the transcriptome data is reliable.