Optimization Of In Vitro Micropropagation System And Rooting Mechanism Of Vaccinium Macrocarpon L

The Vaccinium macrocarpon L.,also known as the Vaccinium macrocarpon L.,is one of the third generation of small berries recognised in the international market in recent years.The fruit of the Vaccinium macrocarpon L.is relatively small and they usually have an oval shape with a smooth surface.Vaccinium macrocarpon L.contain a variety of essential nutrients and have unique medicinal and health functions.In recent years,the demand for Vaccinium macrocarpon L.products in China is increasing year by year,while the rooting rate of Vaccinium macrocarpon L.cuttings is low and it is difficult to propagate them by traditional methods.Plant tissue culture technology is an efficient asexual propagation technology,and the method of tissue culture can obtain virus-free and bacteria-free seedlings,which is more suitable for the needs of rapid development and has important research value for cranberry expansion.In this experiment,based on previous studies,the in vitro micropropagation system of Vaccinium macrocarpon L.histoponic seedlings was further optimised.On the basis of this study,the changes of storage substances,endogenous hormones and oxidase activity and other physiological and biochemical indicators during the formation of adventitious roots of Vaccinium macrocarpon L.seedlings were studied,and the rooting mechanism of Vaccinium macrocarpon L.seedlings was initially revealed.The conclusions of the study are as follows:（1）The controlled univariate experiments revealed that the type of medium,hormone type and concentration,agar concentration,medium pH,stem section site and placement method had significant effects on Vaccinium macrocarpon L.proliferation.The most suitable medium conditions for Vaccinium macrocarpon L.proliferation were:WPM+ZT 0.5 mol/L+8 mg/L agar,pH=4.8.The study of different stem placement sites found that the growth effect of different stem sites of Vaccinium macrocarpon L.was different,the upper and lower stem sites were significantly better than the central part,and the upper stem site grew best,so the positive plugging of stem tips was more effective when Vaccinium macrocarpon L.was proliferated in group culture.（2）Hormone type and concentration,agar concentration and medium pH had a significant effect on the rooting status of Vaccinium macrocarpon L.The most suitable medium conditions for Vaccinium macrocarpon L.rooting were:WPM medium+IBA 1 mg/L+9 mg/L agar,pH=4.8.（3）The exogenous hormone IBA accelerated the metabolism of nutrients in Vaccinium macrocarpon L.seedlings grown in group culture.The development of indeterminate roots was closely related to the dynamic trends of soluble sugars,starch and soluble protein.（4）Changes in the activity of related enzymes in Vaccinium macrocarpon L.seedlings were closely related to the rooting of the seedlings,and IBA significantly affected the activity of oxidative enzymes related to rooting.（5）During the rooting process of Vaccinium macrocarpon L.seedlings,IBA treatment and CK treatment groups had significant effects on the contents of IAA,ABA,GA₃and ZR.The high level of IAA promoted the induction of adventitious roots,the low level of IAA promoted the elongation of adventitious roots,the IBA treatment inhibited the production of ABA,reduced the effect of ABA on the activity of the histoponic seedlings and promoted the formation of adventitious roots,the low level of ZR and GA₃throughout the rooting process facilitated the production of adventitious roots,thus increasing the rooting rate of Vaccinium macrocarpon L.histoponic seedlings.