CONCLUSIONS
The early maturity of young plant (Tables 1 and 2) and fruit, yield (Table 1) and quality of fruit (Table 3) in young trees of Litchi chinensis Sonn. ‘Nuomici’ and ‘Guiwei’ was significantly improved by spiral girdling.
The early maturity of young plant and higher yield in cultivars ‘Nuomici’ and ‘Guiwei’ was promoted by the trunk spiral girdling, this was due to that the vegetative growth was prohibited while the reproductive growth was promoted,.
The spiral girdled young trees had 1 to 2 less springing of twigs annually and their crowns grown more slowly than those in control.
It must be in charge of appropriate degree of spiral girdling. The wound should be healed too early by the gentle spiral girdling, thus it had to do spiral girdling at the same place again before the wound healed. If there was heavy spiral girdling, the wound could not be healed on time, and the wound should be bend up by thin film with good light-permeability.
Trunk spiral girdling of litchi must assembled with the corresponding management. Strong and vigorous young plant should be chosen to carry out trunk spiral girdling. And the fertilization should be enhanced, especially organic fertilizer, watering during the florescence and fruit setting. Young leaves should be extirpated on time, fertilized 4 times by spraying on leaf during flowering and fruit setting.
What corresponding technology for spiral girdling should be adopted for the future? Whether the spiral girdling can make high yield in consecutive year? These were need further research and the improved technical measures.