Study on endogenous hormones and nutrition substances of sijimi longan flowering in summer regulated with growth regulators

In this study, the change of soluble sugar, starch, soluble protein, free amino acid, N6-(2-Isopentenyl) adenosine, Indolylacetic acid (IAA), Abscisic acid (ABA) and Gibrellic acid (GA) during the process of flower formation were studied. Single-factor randomized block design was applied. An area with only a single plant was assigned for the tests. Treatment: When the leaves of the second summer shoots were light green and the buds were not elongated, 500 mg/L of paclobutrazol (PP333) and 126.9 mg/L of ethephon was sprayed to the outer surface of the crown. After 7 days, the mixture of 250 mg/L PP333 and 126.9 mg/L of ethephon were sprayed onto the leaves. The spray was applied evenly as a mist to the plant until the formation of droplets was collected on the outer leaf layers. Water was sprayed onto the leaves in the control group. Study showed that 100% of plants treated flowered and 98.4% of shoots on each plant carried flower panicles. PP₃₃₃ and ethephon increased the content of IPA and ABA. It reduced the GA content in leaves. High level of IPA and low level GA, high level of IAA and ABA improved the flower bud differentiation. During flowering process of Sijimi, higher level of carbohydrate benefited flower formation. The high ratio of C/N in leaves benefited flowering.