‘Arrayana’ mandarin is one of the most cultivated citrus species in Colombia, but this fruit has a short postharvest life and is sensitive to chilling injury (CI) during cold storage. Generating strategies that decrease CI to mandarin can reduce quantitative and qualitative losses postharvest. Brassinosteroids (BR) have been used as a sustainable technology to alleviate CI in fruits and improve postharvest quality. This study evaluated the effect of applying the 24-epibrasinolide analogue (EBR), at doses of 5 mg L⁻¹; DI-31 analogue, at 5 and 10 mg L⁻¹; and control, on the main physical and biochemical characteristics of ‘Arrayana’ mandarin stored at 4 °C for 40 days and, subsequently, 7 days at room temperature (shelf life). The application of EBR and DI-31 analogues reduced the appearance of CI in the exocarp of ‘Arrayana’ mandarin fruits by reducing electrolyte leakage, maintaining membrane integrity, and increasing antioxidant activity and phenol content at the end of cold storage and shelf life. This was especially pronounced with 5 mg L⁻¹ of EBR. Similarly, the BR maintained the postharvest quality of mandarins by reducing weight loss, respiratory intensity, and chlorophyll degradation; increasing β-carotene; and maintaining titratable acidity and soluble solids. Our research reports, for the first time, CI tolerance in Arrayana mandarin using natural (EBR) and spirostanic (DI-31) analogues and illustrates the tolerance functionality of the DI-31 analogue on CI in the fruit postharvest.

The 'Anna' apple is a variety of low requirements of winter chill (250 to 300 chilling hours ≤7.2°C). This apple has essential health benefits and remarkable adaptive potential in tropical and subtropical areas affected by climate change. Thus, this review presents the significance of the 'Anna' apple cultivation, the phenological and eco-physiological modifications, and the current state of agronomic management when continuous crops are managed in tropical highlands. The production of this apple in tropical highlands has outstanding potential to obtain cyclical or continuous harvests (two harvests per year) in certain areas with specific environmental conditions, implementing a particular management system. In plantations, it is crucial to carry out some agronomic practices during the reproductive phenology so that the apple tree does not enter into an endodormancy. These are water stress - defoliation – tie-down branches, and the application of dormancy-breaking agents (flower-inducing compounds). In Colombia, ‘Anna’ variety was introduced in 1985 and is grown in areas with temperatures between 14 and 20°C, altitudes between 1700 and 2800 meters above sea level (m a.s.l.), with bimodal and monomodal rain regimes, and solar brightness between 800 and 2000 hours a year. The harvest is between 100 to 120 days after anthesis, with firmness values of 38.38N, a soluble solids content of 8.58°Brix, and total titratable acidity of 0.7% of the fruit. This documentation indicates a good production with great potential in terms of growth and development, earliness, and quality of the 'Anna' apple tree in Colombian highlands.

The Japanese plum tree is of great importance in the productive development of Colombian fruit growers due to its nutritional contribution to human health, its great adaptability in the tropical highlands, and its good yields. This review presents the current investigative state of physiology of this plant and its management in tropical highlands, including aspects such as its ecophysiology, forced production, gas exchange, flowering, pollination, and fruit development. In Colombia, Japanese plum production systems are adapted between 1,670 and 2,900 m a.s.l., average solar brightness of 1,400 h per year, 12 h photoperiods, temperatures between 14 and 20°C during the day and 6 and 8°C during the night, and rainfall between 700 and 1,600 mm per year. Under these conditions, management can be implemented to produce cyclical crops of the Japanese plum. This management consists of the selection of varieties with low chilling requirement, chemical defoliation, proper fertilization, fruit and green pruning, and the application of chemical substances that promote the breaking of flower buds. Flowering and pollination require a high specificity so that they do not present incompatibility. The growth and development of the fruit requires 1,538 degree days until harvest. This review indicates the great adaptability, management, and production of Japanese plum in the Colombian high tropics.

Water deficit during reproductive development is one of the main constraints on pea (Pisum sativum L.) productivity in tropical highlands. In this study, five varieties with contrasting leaf architectures were evaluated under controlled greenhouse conditions, with and without water deficit applied from the time of pod formation. Key ecophysiological variables, including leaf area index (LAI), radiation extinction coefficient (k), interception efficiency (RIE), radiation use efficiency (RUE), and water use efficiency (WUE), along with yield components, were measured. Deficit significantly reduced biomass, RUE, and yield, although the harvest index (HI) remained relatively stable. Varieties with the afila gene showed greater stability in LAI and WUE, but lower biomass accumulation. Correlation analyses revealed that, under optimal conditions, yield was closely associated with structural and functional traits, a relationship that weakened under stress. These results demonstrate the importance of integrating morphophysiological characteristics into breeding and agronomic management programs to develop more efficient and resilient varieties under water deficit conditions in the high tropics.

Flood events present a significant threat to global agricultural production, with an increasing likelihood of occurrence in the coming years due to climate variability. Commercial species of the genus Solanum are an integral part of the global food economy, due to their nutritional properties. However, their growth is threatened by flooding. The objective of this review was to analyze the current research status of the physiological response to flooding stress in S. lycopersicum, S. tuberosum, S. melongena, S. quitoense, S. muricatum and S. betaceum. A systematic review was conducted in accordance with PRISMA guidelines using four databases. A total of 1,364 relative change data points were obtained from 41 scientific articles to evaluate the behaviour of variables related to water status, photosynthesis and growth under flooded versus non-flooded conditions. The tomato was the most studied species under flood stress, in contrast to the potato, tree tomato, and sweet cucumber. In conclusion, the results demonstrated that flood stress reduced water status, photosynthesis and growth in commercial Solanum plants by 32, 25 and 29%, respectively. These findings indicate that these species are highly vulnerable to waterlogging. This review identifies research gaps in the physiology of crops belonging to the genus Solanum that should be addressed in future studies to contribute to plant tolerance to flood stress.