Pg. 15-18 Effect of pruning date after harvest as it relates to terminal shoot maturation stage shortly prior to flowering, and flowering intensity and cropping in Mauritius litchi trees

A Group of Mauritius litchi trees was pruned on each of a number of dates during January, February and March, 2006, for the purpose of effecting uniformity of terminal shoot and development stage at various times prior to the flowering period in June-July. Flowering intensity as it relates to the stage of terminal shoot maturation in late May, just prior to the flowering period, was in this way assessed. Flowering intensity was greatest in the trees pruned on Feb. 2 or 16. The terminal shoots on these trees were at an advanced stage of maturation on May 29. In the trees pruned on Jan. 19, terminal shoot maturation was such that the stage of readiness of the apical buds on the terminal shoots to break occurred before conditions had become inductive, this resulting in new shoot development occurring prior to the flowering period. Pruning later than Feb. 16 was apparently such that the terminal shoots were not mature enough
for general apical bud break to occur when conditions were inductive. Apical bud development occurred to the greatest extent when conditions were inductive in the trees pruned on Feb. 2 or 16. Number of fruits retained per inflorescence appeared to bear in inverse relationship with tree flowering intensity. However, the relationship was such that fruit yield and flowering intensity were positively related. General pruning of Mauritius litchi trees is required to prevent canopy overcrowding. The results of the current study clearly indicate that the date of pruning is vital regarding tree-capacity to flower. Early February pruning is strongly indicated to maximize the likelihood of a general flowering. Further research may be necessary to determine whether early February pruning is suitable for warmer or cooler regions, or during differing seasons in the region where the study was carried out.