Study On Growth Inhibition Preservation Of Dioscorea Alata And Transcriptome Analysis Under Low Sucrose Stress

As a tropical economic tuber crop with great yield potential,Dioscorea alata is widely planted in southern China.D.alata has been propagated asexually with few or no flowers.When the disease is serious,the germplasm resources will be reduced.At present,in vitro tissue culture is the main way to prevent resource loss.It needs to be subcultured every two months,which is time-consuming and laborious.In order to reduce the cost and save more resources,it is urgent to reduce the growth rate of test tube plantlets.In this study,the effects of different plant growth inhibitors on the growth of test tube plantlets and the recovery of growth after inhibition were investigated.The transcriptome analysis was used to screen the significant differentially expressed genes of growth inhibition under low sucrose stress.The major findings of this work include:1、Different concentrations of sucrose,mannitol,ABA,PP333 were used to treat the tube seedlings of Da40,Da70,Da207.The results showed that 10 g/L sucrose,30 g/L and40 g/L mannitol,2.5 mg/L ABA and 8 mg/L PP333 could effectively inhibit the growth of plants,and the subculture time was extended from once every 2 months to once every 4months.2、The test tube plantlets of D.alata with growth inhibition were restored,and the changes of plant morphology and physiological and biochemical indexes were observed.The test tube plantlets with growth inhibition were restored,and the changes of plant morphology and physiological and biochemical indexes were observed.And there was no significant difference in POD activity,SOD activity and chlorophyll content between sucrose treated and control.There were significant differences in POD activity,SOD activity and chlorophyll content between the other treatments and the control.However,in terms of soluble sugar content,there were significant differences between all treatments and the control.3 、 Transcriptome analysis was used to identify the genes and pathways of low concentration sucrose inhibiting the growth of Da70.The results showed that: with the decrease of sucrose concentration,the up-regulated genes were mainly enriched in MAPK signaling pathway-plant and plant-pathogen interaction.The down regulated genes were mainly enriched in phenylpropanoid biosynthesis,starch and sucrose metabolism and plant hormone signal transduction.