Annual Research & Review in Biology

Dragon fruit, the climbing cacti formerly placed in Hylocereus and now included in Selenicereus, has moved within two decades from a curiosity to a crop promoted by public programmes in India and adopted by growers in Bangladesh, Nepal, Sri Lanka and Pakistan. Its promotion rests on attributes that are repeatedly asserted in policy and extension material: tolerance of drought and degraded land, early bearing, low input demand and high returns. This review evaluates how far peer-reviewed and institutional evidence supports those claims for the agro-ecological, agronomic and market conditions of the Indian subcontinent. A critical narrative design was used, drawing on international and regional scholarly databases, citation tracing and authoritative institutional sources, with appraisal of study design, duration, replication, setting and measurement validity. The evidence is strongest for the crop's crassulacean acid metabolism, which gives high water-use efficiency and tolerance of short droughts, and for the documented benefits of soil modification, canopy management and cross-pollination under Indian field conditions. The same physiological literature identifies upper temperature limits, light sensitivity and long-day flowering requirements that conflict with the characterisation of the crop as broadly climate-proof; heat injury and sunburn already constrain production on the semi-arid Deccan plateau and in western India. Disease and pest records have accumulated quickly, including stem canker, stem and basal rots, anthracnose, viruses, scale insects, ants and fruit flies, but almost all are first reports without epidemiological or yield-loss data. Economic studies consistently report favourable benefit–cost ratios, yet they rely on short time horizons, purposive samples and deterministic price assumptions while measured yields vary several-fold between sources. The subcontinent therefore offers genuine opportunities in water-scarce and marginal environments, provided that site selection, planting material, pollination, shade and postharvest handling are managed deliberately. Confidence in large-scale expansion remains limited by the absence of multi-location cultivar trials, region-specific heat and photoperiod thresholds, quantitative disease surveillance and risk-adjusted market analyses. Coordinated long-term research across the region is required before current expansion targets can be regarded as agronomically and economically secure.