Study on Cutting Cultivation Technology and Rooting Mechanism of Cyclocarya paliurus

Abstract Cyclocarya paliurus is an important rare and multipurpose tree species in China. In view of the difficulty of asexual propagation of Cyclocarya paliurus, this paper explores the technical system of Cyclocarya paliurus cutting propagation from the aspects of cutting collection position and time, tannin removal pretreatment, hormone treatment, sand storage treatment, cutting matrix, environmental factors and physical factors, and discusses its internal physiological changes in the process of cutting rooting. This paper attempts to clarify the physiological characteristics of Cyclocarya paliurus in the process of cutting propagation and rooting. The results of this study can provide technical support and theoretical basis for the cuttings propagation of Cyclocarya paliurus. The results show that the rooting rate of cuttings inserted on the mixture of perlite and vermiculite is up to 32.2 %. In summer, when the middle and upper parts of branches were treated with 300 mg/L rooting powder No. 1 and GGR-6 (Green Growth Regulator-6) mixture, the rooting rate was up to 44.4 %; in winter, the rooting rate of the base of branches was 36.7 % under the same treatment. During the rooting process of Cyclocarya paliurus, a large number of nutrients such as soluble sugar, starch and soluble protein were consumed. SOD (Superoxide Dismutase), POD (Peroxidase), and PPO (Polyphenol oxidase) are closely related to cutting and rooting. High activity SOD and POD are conducive to the expansion of cuttings, and high activity SOD and PPO are conducive to improving the stress resistance of cuttings. Hormone treatment can improve the enzyme activity and make the enzyme activity change in the direction conducive to rooting. The change of endogenous hormone content in cuttings reflects the rooting ability of Cyclocarya paliurus. Substrate heating and hormone treatment can regulate the content of endogenous hormone in cuttings during the rooting process, so as to affect the rooting effect, the stable total nitrogen content in cuttings was conducive to root formation.