Fruitlet abscission (cherelle wilt) is a major factor contributing to lower productivity of cacao plantation in Indonesia. An attempt was made to reduce such cherelle wilt by spraying plant growth retardants (PGRs...Fruitlet abscission (cherelle wilt) is a major factor contributing to lower productivity of cacao plantation in Indonesia. An attempt was made to reduce such cherelle wilt by spraying plant growth retardants (PGRs) on cacao trees at about 10 weeks before flowering session. The treatment was repeated every three weeks. Both the flowering initiation time and the number of flowers on the treated trees were improved significantly. With the most effective composition, flowers were initiated at 24 days after spraying (DAS), where as the flowering initiation was 11-day later in the controls. At the 35 DAS, the chlorocholine chloride (CCC) 2,000 treatment induced about 20-80 folds more flowers than the controls. Extended observation was made to assess the treatment effect on the fruiting capacity. The treatments were found to improve fruiting ability by increasing the number of fruits set on the trees and shortening the time for fruit setting. At 20 weeks after the first spraying (WAS) there were on average 12.57 fruits per CCC 2,000-treated tree, as opposed to only 4.14 fruits per untreated tree. Analyses of the metabolites content in the flower cushions of the trees indicated that the reproductive growth is significantly correlated with the increased metabolites particularly the reduced sugar. Exogenous addition of sucrose to the PGR treatment gave greater improvement mainly in the fruiting. In conclusion, foliar spray of CCC induces flowering of cacao tress in the field that leads to improve the fruitlets productivity.展开更多
文摘Fruitlet abscission (cherelle wilt) is a major factor contributing to lower productivity of cacao plantation in Indonesia. An attempt was made to reduce such cherelle wilt by spraying plant growth retardants (PGRs) on cacao trees at about 10 weeks before flowering session. The treatment was repeated every three weeks. Both the flowering initiation time and the number of flowers on the treated trees were improved significantly. With the most effective composition, flowers were initiated at 24 days after spraying (DAS), where as the flowering initiation was 11-day later in the controls. At the 35 DAS, the chlorocholine chloride (CCC) 2,000 treatment induced about 20-80 folds more flowers than the controls. Extended observation was made to assess the treatment effect on the fruiting capacity. The treatments were found to improve fruiting ability by increasing the number of fruits set on the trees and shortening the time for fruit setting. At 20 weeks after the first spraying (WAS) there were on average 12.57 fruits per CCC 2,000-treated tree, as opposed to only 4.14 fruits per untreated tree. Analyses of the metabolites content in the flower cushions of the trees indicated that the reproductive growth is significantly correlated with the increased metabolites particularly the reduced sugar. Exogenous addition of sucrose to the PGR treatment gave greater improvement mainly in the fruiting. In conclusion, foliar spray of CCC induces flowering of cacao tress in the field that leads to improve the fruitlets productivity.