Exogenous application of ethylene-based compound synchronizes coffee fruit ripening facilitating harvesting with no change in yield and cup quality

In coffee, reproductive development occurs over an extended period, making it susceptible to environmental adversities. This results in sequential flowering events, leading to different initiation points for fruit development and uneven ripening. In this study, we demonstrated that the exogenous application of an ethylene-based product (Eth-bp) accelerates fruit ripening without negatively affecting coffee yield or quality, thereby promoting ripening uniformity and facilitating harvesting. To test our hypothesis, we applied Eth-bp to fruit-bearing coffee plants over two consecutive years, during a three-month period (March to May in 2022 and 2023). Fruit ripening was monitored through manual classification and systematic imaging, alongside ethylene quantification and beverage quality assessments. Ethylene levels in the fruits increased within two hours of product application, reaching 1.8–3.4 ppm/g MF·h⁻¹, and remained elevated across all treatments until the end of the experiment. In the first year, we tested different application times (March to May) and found that the accelerated ripening effect became evident approximately 15 days after application in all treatments. In the second year, similar results were observed, particularly in treated areas, leading to greater synchronization of ripening at harvest. The four-color category classification (Green, Green-Yellow, Cherry, and Raisin) revealed that up to 85% of the fruits were at the cherry stage at harvest, confirming the product’s effectiveness in accelerating and homogenizing ripening. Furthermore, no significant differences were observed among bean categories, and cup quality remained high, scoring above 80 out of 100. Physical analysis of the beans indicated the highest percentage for Flat Beans 17 (42–50%), followed by Peaberries 11 (19–32%). Overall, the Eth-bp demonstrates potential as a valuable plant growth regulator for improving agricultural practices by facilitating fruit collection, synchronizing developmental stages, and advancing the harvest period in coffee. This approach could be explored for application in other crops as well.