Research On Callus Culture And Flavonoids Biosynthesis Of Buckwheat

Buckwheat is not only an important food crops of alpine mountain people in China，butalso has good health benefits．In recent years，pharmaceutical researches have shown thatbuckwheat is rich in flavonoids．The flavonoids have the function of SOD，which caneliminate free radicals；have a good preventive effect on cerebral hemorrhage and anemia；have a positive effect on the control and treatment of hypertension; have an obvious effect onlowering blood sugar and lowering blood lipids; have a certain inhibition of tumor cellgrowth．Increasingly medicinal value of buckwheat has been recognized widely，how toimprove the buckwheat medicinal ingredients become an important research direction of thespecialists．Flavonoids are a class of secondary metabolites in the long-term natural selectionprocess of plants．In recent years，with the environment of global biological resourcesdeteriorating，the market demand for these biologically active substances become more andmore，cell culture technology has become a new way for mass production of secondarymetabolites．The research on buckwheat flavonoids is mainly concentrated in the roots，stems，leaves and grain，the research on buckwheat flavonoids of callus has opened up a newway of thinking．High biological yield of callus is not only paid attention to，but also theincrease of flavonoids content in callus，and ultimately the simultaneous growth of biologicalyield of callus and flavonoids content is a key technology in the production process of theflavonoids．Buckwheat callus induced from the hypocotyl of its sterile seedling were cultivated indifferent light period treatment，different concentration of sucrose，L-phenylalanine andphytohormone（2,4-D、NAA、6-BA）to study the influence of different culture conditions onthe growth of buckwheat callus and flavonoids biosynthesis；callus growth and accumulationof flavonoids of different genotypes of buckwheat were compared．The aim was to explore theoptimal culture conditions of buckwheat callus growth and flavonoids biosynthesis，provide areference for breeding special variety which has high flavonoids in callus，and lay afoundation for the large-scale cell culture and industrial production of flavonoids inbuckwheat．The main conclusions of this paper are as follows： （1）Different light period treatment had no significant effect on the growth of callus；but there were significant differences in flavonoids content and biological yield of flavones incallus under different light period treatment；light treatment significantly promoted flavonoidssynthesis；particularly under the light and dark（16h/8h）processing alternately，flavonoidscontent and biological yield of flavones in callus was almost twice as the dark（16h）treatment．（2）With sucrose concentration increasing，biological yield of callus，flavones contentand biological yield of flavones was increasing；when the sucrose concentration was4%，thebiological yield of buckwheat callus，content and biological yield of flavones was reachedmaximum value; increasing sucrose concentration to5%， the three indicators declinedslightly．（3）With L-phenylalanine concentration increasing，biological yield of callus wasdecreasing， but flavones content and biological yield of flavones was increasing；L-phenylalanine could inhibit the growth of callus，but promote flavonoids synthesis incallus．（4）In the low concentration range，with the concentration of phytohormone increasing，the role in promoting callus growth and flavonoids biosynthesis was more and more obvious；but increasing the concentration of phytohormone to a certain value，callus growth andflavonoids biosynthesis was inhibited；the influence strength of phytohormone on callusgrowth and flavonoids biosynthesis was2,4-D＞6-BA＞NAA；low concentrations of2,4-Dand NAA，6-BA mixture ratio brought a better effect on promoting callus growth andflavonoids biosynthesis； the best combination of different phytohormone promotingbuckwheat callus growth and flavonoids accumulation was1.5m/L2,4-D+0.6m/L6-BA．（5）The differences of biological yield of callus，flavones content and biological yieldof flavones were very significant level in different genotypes of buckwheat．The averagevalue of biological yield of callus of common buckwheat （Beizaosheng， NO．1ofDingtianqiao，Xinong9976and Xinong9978）was significantly higher than the tartarybuckwheat（Jiujiang buckwheat，Xinong9940，Xinong9909and Xinong9920）；the averagevalue of flavones content in callus of tartary buckwheat was higher than the commonbuckwheat，but the average value of biological yield of flavones in callus of commonbuckwheat was higher than the tartary buckwheat．The biological yield of callus，flavonescontent and biological yield of flavones of NO．1of Dingtianqiao were all the highest in fourvarieties of common buckwheat；The biological yield of callus，flavones content andbiological yield of flavones of Xinong9940were all the highest in four varieties of tartarybuckwheat；but the flavones content in callus of Xinong9940was higher than NO．1of Dingtianqiao，the biological yield of callus and biological yield of flavones of NO．1ofDingtianqiao were higher than Xinong9940．...