| Bamboo shoot()is a green health food with high protein,low fat,low sugar and high fiber.Because of its high nutritional value and delicious taste,it is well received by the vast majority of consumers.However,bamboo shoots(Phyllostachys edulis),as the growing buds,have the strong metabolic capacity.After harvest,it was very easy to lignify,and its value of taste would lose for 1-2days under the condition of the room temperature.In the process of lignification,the synthesis and deposition of cellulose and lignin is a very important factor.And the synthesis of lignin is an extremely complex physiological process,involving many enzymes,such as PAL、POD、4CL and CAD.In this paper,the occurrence of lignification of bamboo shoots(Phyllostachys edulis)under room temperature after harvest were studied.Through the analysis of the physiological indexes of four synthetic enzymes and the relative expression level of it of the lignin,the relative expression of lignin biosynthesis and the relationship between lignin biosynthesis and lignin synthase activity were studied.Correlation between the relative expression level and the lignin synthesis,as well as the enzyme activity and the lignin were studied.The study of lignin biosynthesis physiology of bamboo shoots after harvest is helpful for us to grasp the growth characteristics of bamboo shoots,facilitate production management and timely picking,control and delay its aging process,which can achieve maximum economic value.At the same time,it can also lead the processing and production of bamboo shoots after harvest,which is of great significance to prolong the processing period and shelf life.The results of the study are as follows:1.Under the room temperature,as the time changes,the occurrence of lignification occurred on the top of bamboo shoots,the middle of bamboo shoots,the bottom of bamboo shoots.The lignin in the upper part was increased from 4.9% to 6.41%;and the lignin in the middle part was increased from 5.44% to 10.5%;and the lignin in the bottom part was increased from 5.87% to 12.42%.The lignification of the bamboo shoots is a process of advancing from the bottom pare to the upper part.2.Under the room temperature,the changes of the activity of PAL,POD and 4CL in the three parts of bamboo shoots were significantly correlated with the changes in the content of lignin in bamboo shoots,and the three enzymes may be involved in the biosynthesis of lignin..3.The middle and lower three parts of the CAD enzyme activity in the bamboo shoot have reached the highest value at 2h,while the CAD related genes in the upper part of the bamboo shoot are the highest at 10 h,the highest in the middle part at 2h,and the highest at the lower part at 18 h.4.With the change of time,the expression level of PAL,POD and 4CL genes in the three parts of bamboo shoots are positively correlated with the distribution of the content of lignin respectively,and these three genes may be involved in the biosynthesis pathway of lignin. |
