Submitted to: Journal of Agriculture of the University of Puerto Rico
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 12, 1997
Publication Date: N/A
Interpretive Summary: Puerto Rico produces about 300 million plantain fruits annually with a farm gate value of $35 million. Most of the production originates from the false-horn Maricongo clone which bears unstable bunches containing 3 to 8 hands and 24 to 60 fruits. A mature-green plantain fruit is graded marketable if it weighs 270 g or more. In an attempt to increase yield, improve fruit quality, and stabilize bunch fruit production, we subjected the French-type Superplatano bunch which produces many hands and undersized fruits to various pruning treatments. The unpruned false-horn Maricongo bunch was used as a control. Bunch pruning substantially increased fruit size and weight at the expense of reducing bunch size to four or five hands. The Superplatano bunches pruned to five hands produced 66 marketable fruits and weighed 20.7 kg. Bunch mean fruit weight was 314 g, well over the 270 g weight criterion used for local marketable grade fruits. Fruits in the last hand of the Superplatano bunches pruned to fiv hands were similar in size and weight to those corresponding to the same numerical hand of the unpruned Maricongo. The Superplatano with bunches pruned to five hands yielded 27% more fruits of acceptable marketable grade than the unpruned Maricongo. This yield increment will compensate for the continuous increase in costs of production that otherwise must be passed on to the consumers.
Technical Abstract: The French-type Superplatano (Musa, AAB) clone planted on a highly weathered Ultisol under supplemental irrigation was subjected to various bunch (raceme) treatments. Two weeks after bunch emergence the immature racemes were pruned to either four, five and six uppermost hands. Subsequently, some of the pruned racemes were sprayed with a hormone (Pro-Gibb) solution containing 50 ppm of gibberellic acid while others wer not sprayed. Some bunches were immediately bagged and others were left unbagged. The false-horn type 'Maricongo' plantain with unpruned, unsprayed and unbagged racemes was used as a control. Hormone spraying and bagging had no significant effect on bunch and fruit traits. Pruning, however, significantly affected bunch number of fruits and weight, bunch mean fruit weight, and individual fruit traits in the distal hand. A reduction in number of hands from six to four significantly reduced bunch size at the expense of a substantial increase in bunch mean fruit weight, thickness, length and weight of individual fruits in the distal hand. The 'Superplatano' with the bunch pruned to five hands averaged 66 marketable fruits and weighed 20.7 kg. Bunch mean fruit weight was 314 g , well over the 270 g weight criterion used for local marketable grade fruits. These bunches contained significantly more fruits and were heavier than the unpruned 'Maricongo' racemes with 7.4 hands. Only bunches pruned to four hands however, had a bunch mean fruit weight similar to the unpruned 'Maricongo'. Fruits in the distal hand of the `Superplatano' bunch pruned to either four or five hands compared in thickness, outer length and weight to those corresponding to the same numerical hand of the unpruned 'Maricongo' raceme.