During ripening, ‘Hass’ avocado skin changes from green to purple/black. Low-temperature storage with a controlled atmosphere (CA) is the most widely used method for avocado storage; however, few studies have simulated this technology and considered the days of regular air (RA) storage prior to CA storage. Herein, the effect of delaying the storage of ‘Hass’ avocado (>30% dry matter) in a CA was examined. Long-term storage conditions (5 °C for 50 days) corresponded to (i) regular air storage (RA), (ii) CA (4 kPa O₂ and 6 kPa CO₂) and (iii) 10 days in RA + 40 days in a CA and (iv) 20 days in RA + 30 days in a CA. Evaluations were performed during storage and at the ready-to-eat (RTE) stage. Skin color remained unchanged during storage, but at the RTE stage, more color development was observed for fruits stored under CA conditions, as these fruits were purple/black (>50%). At the RTE stage, the anthocyanin content increased, and compared to fruit under RA, fruit under a CA contained a five-fold greater content. A 20-day delay between harvest and CA storage increased the fruit softening rate and skin color development after cold storage, reducing the effectiveness of CA as a postharvest technology for extending storage life.

1–Methylcyclopropene (1–MCP) is used for extending the postharvest life of the avocado during storage. Evaluated the effect of 1–MCP application at different times after harvest, i.e., 0, 7, 14, and 21 d at 5 °C, to identify the threshold of the ethylene inhibition response in “Hass” avocado. Our results showed that fruits from two maturity stages at harvest: low dry matter (20–23%) and high dry matter (27%). Changes in ethylene production rates and transcript accumulation of genes involved in ethylene metabolism were measured at harvest and during storage. 1–MCP treated fruit up to 14 d of storage showed similar values of firmness and skin color as fruit treated at harvest time. In contrast, when the application was performed after 21 d, the fruit showed ripening attributes similar to those of the untreated ones. To further understand the molecular mechanisms responsible for the lack of response to 1–MCP at 21 d of storage, transcriptomic analysis was performed. Gene ontology analyses based on the DEG analysis showed enrichment of transcripts involved in the ‘response to ethylene’ for both maturity stages. All genes evaluated showed similar expression profiles induced by cold storage time, with a peak at 21 d of storage and an increased softening of the fruit and peel color. This was a two-year field study, and results were consistent across the two experimental years. Our results should help growers and markets in selecting the optimal timing of 1–MCP application in “Hass” avocados and should contribute to a deeper understanding of the molecular mechanisms of the avocado ripening process.

Preharvest climatic conditions and irrigation management are decisive determinants of avocado postharvest performance. Avocado trees are highly susceptible to the water regimen, conditions that disrupt carbon assimilation, mineral nutrient uptake, and biomass partitioning. This study evaluated the effects of deficit irrigation imposed during early stages of fruit growth, coinciding with active cell division, on fruit development and postharvest quality of ‘Hass’ avocado. Deficit and excess irrigation induced physiological stress, reducing stem water potential (≈−1 MPa) and altering photochemical efficiency, while F_V/F_M remained unaffected. Fruit growth was strongly affected, with weight reductions of up to 26% during development and 22% at harvest under severe deficit, resulting in fruits becoming more yellowish-green. In contrast, excessive irrigation promoted larger fruit with darker green skin, with delayed maturation. Metabolomic revealed that the fruit developmental stage was the main driver of metabolic variation, while irrigation effects were minor and stage-dependent, limited to osmotic-related metabolites such as GABA. These findings indicate that early-season water imbalances primarily affect fruit growth through changes in water relations rather than metabolic reprogramming, highlighting the importance of precise irrigation management during critical developmental stages. Fine-tuning water supply during early developmental stages is a strategic tool for optimizing fruit size and postharvest quality in avocado.