Study On The Regulation Mechanism Of Exogenous Hormone And Illumination Temperature Treatment On Seed Germination Of Cistanche Deserticola Y.C.Ma

Cistanche deserticola Y.C.Ma is a valuable traditional Chinese medicine resource with a long history of medicine and food.With the further development of C.deserticola resources and further exploration of the value of medicine and food,the domestic demand and export volume of C.deserticola increased year by year.Meanwhile,C.deserticola’host Haloxylon ammodendron,has the ecological value of windbreak and sand fixation,and greatly promotes the artificial cultivation of C.deserticola.At present,the process of artificial breeding of C.deserticola,it is faced with problems such as difficulty in seed germination,low inoculation rate,inability to measure the strength of seed germination power,and preservation of seeds.These problems severely restricted the large-scale cultivation and industrial development of C.deserticola.The effects of two kinds of exogenous hormones,illumination and temperature on the seed germination of C.deserticola and the physiological characteristics of C.deserticola were studied in this paper.The main conclusions are as follows:1.The seed of C.deserticola is fine,consisting of two parts:seed embryo and seed coat,and the proportion of seed embryo is only part of the seed.There is no water absorption barrier in seeds.The seeds contain certain germination inhibitors,and after the seed imbibition,there are still the production and transformation of the inhibitory substance.2.The synergistic induction of the seeds of C.deserticola by fluridone and gibberellin can break seed dormancy and promote germination.The synergistic combination of the optimal fluridone and gibberellin was screened out:10mg/L fluridone pretreatment for 36h+dark culture with 25mg/L gibberellin.In addition,single fluridone pretreatment with C.deserticola seeds can promote seed germination,10mg/L fluridone pretreatment for 36h,and the seed germination rate was 32.67%.But fluridone has little effect on seed germination during germination.The optimal effect of single gibberellin on seed germination was:distilled water pretreatment for36h+dark culture with 25mg/L gibberellin,and the seed germination rate was 7.33%.3.C.deserticola seeds soaked in distilled water prior to germination and supplemented with illumination treatment can promote seed germination and seed germ tube growth.During seed germination,illumination has an inhibitory effect on the seed germination.Illumination for C.deserticola seed germination of the best results showed:soaked in distilled water and additional illumination treatment for36h+dark culture with 25mg/L gibberellin,the seed germination rate was 33.33%.4.In five storage conditions of 4°C,4°C stratification,25°C,35°C,and room temperature,stratification at 4°C can break seed dormancy and promote seed germination.The seed of 0¹20 days after 4°C stratification,and the seed germination rate was increased.After 4°C stratification for 120°C days,dark culture with 25mg/L gibberellin,the seed germination rate was 30.00%.The storage period was 0¹20days,the five storage conditions had no significant effect on the viability of C.deserticola seeds.The viability of seeds after storage was from low to high:35°C<room temperature<25°C and 4°C<4°C stratification.The seeds stored at 35°C had the greatest impact on seed viability,but before and after storage,seed viability decreased by only 2.33%.5.The seeds of C.deserticola were stored under 4°C,4°C stratification,25°C,35°C and room temperature.With the increase of storage time,the electrical conductivity,MDA content,soluble sugar content,soluble protein content,SOD activity and CAT activity of the seeds varied with different degrees.The seeds were stored at 4°C and 4°C stratification,the peroxidation degree of the membrane was lighter,less consumption of inclusions,the activity of SOD and CAT enzymes was higher,and the seed membrane system could be well protected.When seed was stratificated at 4°C for 120 days,seed electrical conductivity and MDA content were the lowest,soluble protein content was highest,and SOD activity and CAT activity were the highest.However,after 120 days storage at 4°C,the soluble sugar content was the highest,and the remaining indicators are only inferior to the 4°C stratification condition.To sum up,the effect of fluridone,gibberellin,illumination and storage conditions on the germination of C.deserticola seeds was shown as follows:4℃stratified 120d+dark culture with 25mg/L GA₃,the germination rate was 30.00%<10mg/L FL pretreatment for 36h+dark culture with distilled water,the germination rate was 32.67%<soaking and illumination for 36h+dark culture with 25mg/L GA₃,and the germination rate was 33.33%<10mg/L FL pretreatment for 36h+dark culture with 25mg/L GA₃,the germination rate was 59.33%.