Climbing cacti with edible fruits have been proposed as new dryland fruit crops because their high water-use efficiency reduces water requirement. One lineage of climbers in the cactus family, the Hylocereus group of Selenicereus, includes several species that produce edible fruits and is currently cultivated around the world. Fruits are known as pitahayas, pitayas or dragon fruit. Here, by means of ecological niche-based modelling and analytical hierarchical modelling, the optimal areas for cultivating the three main species of this group in Mesoamerica – Selenicereus costaricensis, Selenicereus ocamponis and Selenicereus undatus – are identified. Data on distribution, physiological requirement and host preferences are taken into account to carry out ecological modelling for current and future scenarios of climate and determine its impact on cultivation. Two MIROC climatic future models, one optimistic (ssp216) and a pessimistic (ssp585) were selected and 554 records from Mexico and Central America were gathered. For all three species, temperature and precipitation seasonality, and solar radiation were the most significant variables in the niche modelling. In addition, for S. undatus the most important hosts, three species of mesquite legume trees were significant to forecast suitable areas for planting. Large areas on the Pacific side from Sinaloa to Costa Rica were predicted as favourable for cultivating the studied three species. Future scenarios of climate change predicted increase of suitable areas for two species and in particular for S. undatus the increment was the largest. Therefore, dragon fruits are corroborated as promising fruits in view of climate change.

Introduction. Still practically unknown in the mid-1990s in Europe, pitahaya (Hylocereus spp.) is now a full member of the ‘small exotic fruits’ category in shops. Nevertheless, these species are not very well known. The aims of our work were first to evaluate thoroughly the literature currently available on Hylocereus and secondly to supplement this review by agronomic works not yet published. Knowledge of Hylocereus. The study includes a presentation of the origin, botany, morphology and floral biology of the principal species cultivated within the Hylocereus genus and suggests a key for determination. Cultivation techniques. The agronomical practices used in Hylocereus orchards are broached: multiplication, cultivation practices (supports, density, pruning, mineral nutrition, irrigation, etc.), pollination and harvest. Pests and diseases are cited too. Physico-chemical composition of fruits. This work draws up a review of different studies regarding pitahaya composition, micronutrients and pigments. Post-harvest and processing. The life of the fruit after harvest (conservation and storage life) is approached as well as the various possibilities of processing. European market. The European market is analyzed for the various cultivated species of Hylocereus (imported quantity, market segment, origin of production, etc.) and its evolution prospects are evoked. Conclusion. Our review highlights the fact that the interest shown in these pitahayas is recent and, for these reasons, more detailed knowledge on these species is required (agronomic, genetic and technological).

Introduction. Red-purple pitahaya (Hylocereus sp.) is a promising crop grown commercially in dry regions of Central America. Both its skin and flesh are characterized by being a glowing, deeply red-purple color. Materials and methods. The main physicochemical characteristics of three commercial cultivars of red pitahaya were assessed, including total phenolic compounds contents, total betacyanins, vitamin C and oxygen radical absorbance capacity (ORAC). Thermal stability of betacyanins at different temperature and pH was also assessed. Results and discussion. Pitahaya fruit has a low vitamin C content ranging from (116 to 171) µg·g–1 of fresh pulp without seeds, but it is rich in betacyanins [(0.32 to 0.41) mg·g–1] and phenolic compounds [(5.6 to 6.8) µmol Eq gallic acid·g–1]; it has a high antioxidant ORAC value of (8.8 to 11.3) µmol Eq Trolox·g–1. Visible spectra of aqueous fruit extracts were very similar to that of pure betacyanin. Indeed, the characteristic color of juice diluted to 1% presents a high hue angle (H° = 350º ± 3) and high chroma values (C* = 79 ± 2). Thermal stability of pitahaya betacyanin decreases with pH, but it remains compatible with industrial utilization as a colorant (half-time = 22.6 min at 90 °C at pH = 5 of the fruit) and was found to be very similar to that previously reported for beetroot. Conclusions. Pitahaya juice combines the functional properties of a natural food colorant with high antioxidant potency.

La pitaya (Hylocereus sp.) en culture de diversification à l'île de la Réunion : stratégie d'accompagnement de son développement.Résumé – Le patrimoine fruitier de l'île de la Réunion. Parmi les quelques 138 espèces fruitières qui composent le patrimoine fruitier de l'île de la Réunion, seules quelques-unes d'entre-elles sont véritablement cultivées. Pourtant, certaines autres pourraient séduire les consommateurs avides de nouveauté. Critères de présélection pour une culture de diversification. Face à ce constat, une présélection a été réalisée afin d'identifier des espèces fruitières nouvelles, candidates à la diversification pour l'île de la Réunion ; les critères de choix ont été : l'attractivité du fruit, sa commodité à être consommé, son goût, l'aptitude à sa conservation, la rentabilité de l'espèce, etc. La pitaya (Hylocereus sp.) a alors été retenue. Ce choix a ensuite été validé par une enquête auprès de consommateurs réunionnais. Développement de la pitaya à l'île de la Réunion. Le développement de cette nouvelle culture a été réalisé en trois étapes : identification des contraintes agronomiques liées à l'intensification de cette culture et recherche de solutions ; acquisition des techniques culturales de base et sensibilisation du grand public ; prise en compte des contraintes des agriculteurs et accompagnement commercial du nouveau produit. Conclusions. Les qualités commerciales de la pitaya (couleur et forme attrayantes), l'enthousiasme des consommateurs et la motivation des agriculteurs envers cette nouvelle espèce font de H. sp. une véritable opportunité de diversification pour l'île de la Réunion alors que, il y a 7 ans, le fruit de cette espèce était totalement inconnu sur l'île.