Yield and nutritional quality of calabash tree fruit (Crescentia cujete) in silvopastoral systems: implications for on-field management

The objective was to assess the effect of shade, pruning, and harvest time (seasonality) on the yield and nutritional composition of calabash tree fruit ( Crescentia cujete ). This fruit is used as livestock feed in silvopastoral systems in the dry South American tropics. Two hundred calabash trees were randomly distributed in a split-plot experimental design with four experimental treatments (n = 50) defined as: not shaded-not pruned trees (NSh-NPr), not shaded-pruned trees (NSh-Pr), shaded-not pruned trees (Sh-NPr) and shaded-pruned trees (Sh-Pr). Trees were monitored each 4 months over a 2-years total period and its fruits were classified as ripe, unripe and fallen fruits, whereas ripe fruits were collected and analyzed by its nutritional quality. The shade effect significantly decreased fruit yield. There was a significant interaction shade × time effect. The fruit yield decreased in October 2022 and February, June and October 2023, as well as the average fruit weight at the same harvesting times (except in October 2022). Pruning also showed a significant effect with lower weight and fruit yield. A significant interaction effect of pruning × time was reflected on lower unripe and fallen fruits, both in June and October 2023 (rainy season). Shade, pruning and seasonality did not affect the nutritional quality of fruits. Not pruned calabash tree under sunny conditions has proven to be the best strategy in order to obtain the greatest fruit yield for livestock feeding, ideal for converting conventional herbaceous pastures and deforested landscapes into silvopastoral systems as a sustainable alternative for livestock production in dry tropical savannas.