A Comparative Study On Methods For Detecting The Vulnerability Of Xylem Embolism In Three Woody Plant Species

In recent years,there have been numerous reports on the use of different detection methods to establish the xylem vulnerability curve of xylem in plants.The study found that the xylem embolism characteristics of plants obtained from different detection methods were significantly different for some plant species,and the differences were related to the structural characteristics of the plant xylem.Therefore,the formation mechanism of plant xylem embolism in various detection methods,as well as the selection and optimization of methods for the detection of the xylem vulnerability of specific species,have become scientific and technical problems that need to be solved.In this paper,the materials of different lengths of conduit were studied which were the annual branches of Robinia pseudoacacia L.,Prunus persicae.and Acer mono maxim.The lengths of the conduit of Robinia pseudoacacia L.,Prunus persicae.and Acer mono maxim were measured by air injection method,and The bench top dehydration,Cochard Cavitron centrifuge method,Sperry centrifuge method was used to establish the embolism vulnerability curves of the annual branches o Robinia pseudoacacia L.,Prunus persicae.and Acer mono maxim,and to explore the reliability of different methods to establish the vulnerability of embolism,to explore the relationship between conduit length and embolism vulnerability;to use Sperry with customized rotor centrifuge was used to measure the embolism variability of samples of different lengths of Robinia pseudoacacia L.,Prunus persicae.and Acer mono maxim,and the effect of the opening conduit artifact on the establishment of the embolism vulnerability curve was examined.The degree of embolism in Robinia pseudoacacia L.,Prunus persicae.and Acer mono maxim was observed by fluorescence microscopy.The main conclusions are as follows:1.The lengths of the three species of Robinia pseudoacacia L.,Prunus persicae.and Acer mono maxim were ranked as follows:Robinia pseudoacacia L>Prunus persicae.>Prunus persicae,of which the length of the conduit was the largest.The vulnerability(P₅₀)of the embolism of Robinia pseudoacacia L.,Prunus persicae.and Acer mono maxim established by The bench top dehydration,Cochard Cavitron centrifuge method,and Sperry centrifuge method was ranked as follows:Robinia pseudoacacia L>Prunus persicae.>Prunus persicae,among which Robinia pseudoacacia L.was more prone to embolism than other two species.Acer mono maxim anti-embolism ability is the strongest.The analysis shows that the length of the catheter may be positively correlated with the vulnerability of the embolism;2.The embolism vulnerability curves of the Robinia pseudoacacia L.,Prunus persicae.and Acer mono maxim were all"s"shaped by The bench top dehydration.The embolism vulnerability curve of the Robinia pseudoacacia L.established by the Cochard Cavitron centrifuge method and the Sperry centrifuge method was all"r"shaped,Cochard Cavitron centrifuge method and Sperry centrifuge method established the embolism vulnerability curve of Prunus persicae.and Acer mono maxim were"s"shape.The vulnerability of embolism of Robinia pseudoacacia L.established by these three methods was:The bench top dehydration>Sperry centrifuge method>Cochard Cavitron centrifuge method,the difference was significant（P<0.05）;However,the difference in the vulnerability of embolism of Prunus persicae.and Acer mono maxim established by these three methods was not significant（P<0.05）;3.Sperry centrifuges were used to measure the differences in embolism vulnerability between samples of different lengths of Robinia pseudoacacia L.,Prunus persicae.and Acer mono maxim（P<0.01）.Using 14.4 cm and 27.4 cm centrifuge rotors,the embolism vulnerability curves for the corresponding length of Robinia pseudoacacia L.branches were all"r"shaped.The vulnerability curves of Prunus persicae.and Acer mono maxim embolism detected by two kinds of centrifuge rotors are all"s"shape,and the results of this study do not support the theory of open conduit artefacts;4.Robinia pseudoacacia L.,Prunus persicae.and Acer mono maxim have strong embolization and recovery capabilities.