Effects Of Temperature,Drought And UV-B Irradiation Time On Celery Growth And Flavonoids Accumulation

Celery(Apium graveolens L.),an annual or biennial herb,belongs to the umbrella family.The origin of celery is Europe,close to the Mediterranean Sea,began to grow in China in fifteenth Century.Because Celery contains a variety of nutrients and medicinal ingredients and loved by the people,and gradually become one of the daily consumption of vegetables.Celery contains a variety of flavonoids,apigenin and luteolin content was the highest.Flavonoids have good antioxidant effects,anti-tumor and anti-cancer effects,etc.,in recent years by the researchers concerned.In this paper,Celery was used as the experimental material.The growth and the flavonoids accumulation of Celery in the environment under temperature,drought and UV-B irradiation were studied by matrix cultivation method.In order to investigate the effects of environmental factors on the growth and flavonoids synthesis of celery,And to provide the basis for improving the content of flavonoids in Celery by cultivation techniques.The main findings are as follows:1.As the temperature increasing,proline,soluble sugar,apigenin and luteolin content and SOD,POD,CAT,PAL,CHS,CHI activities and the relative expression of PAL,CHS and CHI genes in celery showed a trend of increasing first and then decreasing.H2O2 and O2-content decreased first and then increased.Under low temperature(8?/10?),the activity of PAL,CHS and CHI in celery reached the maximum and showed that the leaf was larger than that of petiole.The relative expression of PAL,CHS and CHI gene was similar to that of the corresponding enzyme activity.Apocynum and Flavonoids were the highest,showing that the leaves were much larger than petiole.The contents of proline and soluble sugar were the highest,and there was no significant difference between leaf and petiole.The content of H2O2 and O2-was the lowest,and there was no significant difference between leaf and petiole.The activity of SOD,POD and CAT reached the maximum value,and the activity of SOD enzyme in petiole was higher than that of petiole,and the activity of POD and CAT showed no significant difference between leaf and petiole.At the same time,the growth index of celery decreased to some extent,but there was no significant difference compared with the control.It can be seen that the lower temperature can promote the accumulation of flavonoids in celery,the optimum temperature is 8 ?/10 ?(evening/day).2.Under mild drought(10%PEG6000 treatment)treatment conditions,there was no significant difference in the growth index of celery compared with the control,PAL,CHS and CHI were significantly increased,and the leaf was larger than petiole.The relative expression of PAL,CHS and CHI genes in different treatments and different parts of celery was similar to that of corresponding enzymes.Apigenin and luteolin content compared to the control increased significantly,and the leaf was much larger than the petiole.The contents of proline and soluble sugar were significantly increased,and there was no significant difference between leaf and petiole.H2O2 and O2-were significantly decreased,showing no significant difference in leaf and petiole.The activities of antioxidant enzymes were increased,and the activity of SOD enzyme in leaf was higher than that of petiole.The activities of POD and CAT showed no significant difference in leaf and petiole.Severe drought(30%PEG6000 treatment),the content of flavonoids decreased significantly,the content of free radical increased significantly,and the activities of SOD,POD,CAT,PAL,CHS and CHI decreased,and the relative expression of PAL,CHS and CHI decreased in celery.It can be concluded that the appropriate degree of drought treatment can promote the synthesis and accumulation of flavonoids in celery,with mild drought(10%PEG6000 treatment)as well.3.with the extension of UV-B irradiation time,Celery growth is affected to varying degrees,apigenin and luteolin content,SOD,POD,CAT,PAL,CHS and CHI activities and the relative expression of PAL,CHS and CHI genes in celery showed a trend of increasing first and then decreasing.Chlorophyll content decreased gradually,The content of H2O2 and O2-decreased first and then increased.After 4 days of UV-B irradiation,the growth index of celery decreased to some extent,but there was no significant difference compared with the control,the activities of PAL,CHS and CHI reached the maximum value,and the leaf was larger than petiole.The relative expression levels of PAL,CHS and CHI genes in different treatments and different parts of celery were consistent with the changes of their corresponding enzyme activities.Apocynum and Flavonoids were the highest,showing that the leaves were much larger than petiole.The content of Chlorophyll has a certain degree of decline.The content of H2O2 and O2-in celery were the lowest,and there was no significant difference between leaf and petiole.The activity of SOD,POD and CAT reached the maximum,and the activity of SOD enzyme in leaf was higher than that of petiole.The activity of POD and CAT showed no significant difference between leaf and petiole.Therefore,the appropriate time of UV-B irradiation treatment can promote the synthesis of flavonoids in celery,the optimal irradiation time is 4d.