Study on the cutting technology of chayote (Sechium edule) and the physiological mechanism of rooting regulation by exogenous hormones.

BACKGROUND: 'Tuershao' is a new chayote (Sechium edule) variety whose tuberous roots and tender shoots are edible. These parts are rich in beneficial substances, including amino acids, proteins, phenolic compounds, flavonoids, cucurbitacin, and selenium, demonstrating their unique value. However, its ovary cannot develop into a mature fruit, and cutting techniques help to achieve the breeding of 'Tuershao'.

RESULTS: This study found that using peat soil as the substrate and treating semi-hard branches with 1.0 g·L⁻¹ indole-3-butyric acid (IBA) achieved the highest rooting rate of 94.33%, with the maximum values in root length, root surface area, root volume, and root diameter. Additionally, exogenous hormone treatment led to greater fluctuations in the contents of soluble sugar, starch, and soluble protein in 'Tuershao'. The activities of catalase (CAT), polyphenol oxidase (PPO), peroxidase (POD), and superoxide dismutase (SOD) were also enhanced. The contents of endogenous hormones such as auxin (IAA), cytokinin (CTK), and gibberellin A3 (GA3) increased, while abscisic acid (ABA) decreased.

CONCLUSIONS: Treating semi-hard branches with 1.0 g·L⁻¹ IBA on peat soil shows the best effect in promoting rooting of 'Tuershao' cuttings. Exogenous IBA can promote nutrient metabolism, enhance antioxidant enzyme activities, and regulate endogenous hormone levels in 'Tuershao' cuttings, thereby further promoting rooting.