Flower induction with chemicals in 'Cat Hoa Loc' mango trees grown in the Mekong Delta in Viet Nam.
Tran Van Hau, Radanachaless T., Ishihata K., Shioya T.
Author Affiliation: Crop Science Dept., College of Agriculture, Can Tho University, Can Tho City, Vietnam.
Japanese Journal of Tropical Agriculture 46 : 59-65
Abstract : Off-season floral induction in 'Cat Hoa Loc' mango by using paclobutrazol, potassium nitrate and Chemical Compound Inducing Flowering, a chemical product developed at Can Tho University (CTU) consisting of potassium nitrate, phosphoric acid and minor elements, was carried out in Cao Lanh district, Dong Thap province, Vietnam from May 1996 to May 1997. Paclobutrazol was applied at a rate of 5 g per tree by collar drenching, while KNO3 and CTU were used at a concentration of 15 g/l and applied twice as a foliar spray. The results showed that the floral induction chemicals were able to induce flowering in 'Cat Hoa Loc' mango in September except for the treatment of 6-year-old trees with KNO3. Off-season flowering was extended until the end of December. Paclobutrazol was the most effective chemical compared with both KNO3 and CTU. It induced flowering at 85 days after the treatment 4.3 times in approximately 15.6% of the total number of shoots per tree compared to less than 3 times and less than 6% of the total number of shoots per tree in the case of other chemicals and control treatments. Flowering of the control occurred in November. Off-season harvest extended from December 1996 to March 1997. The fruits in which flowering was induced by paclobutrazol were harvested in early December, 85 days after flowering (4 harvests). The highest off-season yield (35.3 kg/tree) was obtained with the paclobutrazol treatment in 8-year-old trees. However, the chemical treatments did not promote flowering in 6 and 7-year-old trees.