The 2009 ASHS Annual Conference

Research characterizing the florigenic promoter of ‘Keitt' mango during cool, sub-tropical conditions demonstrated that ¼ leaf per stem was sufficient to induce flowering in 95% of initiating lateral shoots on deblossomed stems. In another experiment, three leaves on a donor stem were sufficient to induce flowering in 100% to 80% of initiating lateral shoots on the donor and five adjacent defoliated receiver stems, respectively. Similar experiments in the warm tropics of Colombia determined that four leaves per stem were necessary to induce 50% flowering shoots in ‘Tommy Atkins' trees and 20% flowering in ‘Keitt' trees. The reciprocal proportions of shoots in each case were vegetative. Five leaves on donor stems of ‘Tommy Atkins' induced 70% to 20% flowering shoots on the donor and three adjacent receiver stems, respectively. The levels of FP made in ‘Keitt' leaves during warm temperatures were estimated to be 3% of that produced in cool temperatures. The amount produced by ‘Tommy Atkins' leaves in the tropics was about 8% that of ‘Keitt' leaves in the subtropics.