The Establishment Of Rubber Tree (Hevea Brasiliensis) 7-33-97 Suspension Cells And Activation Of Its Defense Responses Treated With Riboflavin

Plant can induce a series of defense responses including such as reactive oxygen species, secondary metabolites accumulation and resistance related gene expression which can resist the invasion and expansion of resistantpathogens.tr-eated by Elicitor (elicitor). Riboflavin(vitamin B2),as a coenzyme,produced fro--m plants and microorganisms in natural conditions,plays an important role in many physiological activities of microorganisms, animal and plant. Due to its g-ood dispersion, fast growth and easy to control,cell suspensions culture as a ki-nd of plant biotechnology research mean, has been widely used in the study o-f cytology, biochemistry, genetics, molecular biology and application of plant b re--eding. Previous studies showed that riboflavin as elicitor can improve plant di-sease resistance.The main results of this study are as follows:1?Take the callus got from the anther of Hevea brasiliensis (7-33-97) afte-r induced by MS culture medium as material, we have established the table s--uspension cells which can be as the main material for follow-up experiments by the the improved MS medium based on the selection of the optimal concen tration of several key hormones and the source produced the main carbon sucr--oseon.The results showed that by adding l.Omg/L 2,4-D, 0.5mg/L NAA, 1.5m g/L KT, 30g/L sucrose in MS medium under the nutritional environment, we c-an get the cell suspensions which are in good stability and growth rate.Those cells provide an effective guarantee for the subsequent experiments which need the large amount of experimental materials; suspension of pH value of the liq uid culture there is a correlation between the growth rate and the change of ce 11s. When the cell suspensions in the logarithmic phase of rapid growth, the va-lue of pH in the liquid is gradually increased and the growth suspension cells in the long culture time slowed down, the value of pH in the culture was dec-reased. Therefore, in order to establish a stable and great rapid growth of the suspension cells system,6?8d is the best.2?In this research, the mechanism of induction was preliminarily explore-d by using the rubber tree (Hevea brasiliensis) 7-33-97 suspension cells as ma t-erials with riboflavin treatment. The results shown that the defense responses elicited by rubber tree (Hevea brasiliensis) 7-33-97 suspension cells with ribofla vin treatment, which included an oxid ative burst, extracellular alkalinisation, in c-reasing of phenylalanine ammonia lyase (PAL) and peroxidase (POD) activitie s, and expression of two defense-related genes HbPR-1 and HbNPRl. Alkalinis-ation response was induced by rubber 7-33-97 suspension cells with riboflavin treatment, but inhibitied and partially inhibitied by calcium channel inhibitor L-aCl3 and protein kinase inhibitor K252a, respectively, which showed that protei-n phosphorylation have been involved in the transmission of the disease resist--ance processd. These results suggested that riboflavin can induced a series of defense responses in rubber 7-33-97 suspension cells, in which SA-dependent si-gnal pathway may be involved.