Lighting the way: Radiation use efficiency and phenotypic variation of candlenut (Aleurites moluccanus), a tropical oilseed tree

The candlenut tree ( Aleurites moluccanus (L.) Willd) is gaining interest as a potential feedstock for bioenergy development, with particular attention to its oil, which constitutes ∼60 % of its seed endosperm. Despite its many uses and history of human relationships, its productivity and role in ecosystem function remain uncertain. This review evaluates candlenut literature through the lenses of radiation use efficiency (RUE) and phenotypic variation as a function of genetic, environmental, and management (GEM) factors and their interactions. These analytical lenses support agronomic efforts as well as ecological modeling to evaluate the sustainability of candlenut production. Yield reports from Indonesia, the primary country of candlenut production, average 17.66 kg tree -1 , while older reports range between 30-91 kg tree -1 . This discrepancy likely stems from inconsistent reporting of product type, tree conditions, and growing conditions but may also point to opportunities for tree improvement. Though sparse, data related to conversion efficiency, hydraulic traits, and reproductive phenology suggest that candlenut may be sensitive to the availability or seasonality of moisture. Unique leaf tendencies have been described in Indonesia and Hawaiʻi, though interactions between genetic and environmental variability remain untested. Candlenut features in management applications including agroforestry, successional plantings, and monotypic stands. Variation in planting density, rotation length, and intercropping are likely to influence the tree’s interception efficiency and its ability to balance productivity and ecosystem services. These results have immediate utility to inform production, modeling efforts, and research directions. However, interactions with local ecologies, existing markets, and cultural practices must also be investigated.