The effects of PGPR and post-harvest melatonin applications on the post-harvest physiology in mushroom (agaricus bisporus) cultivation

In this study, the effects of pre-harvest spraying with modified atmospheric conditions and PGPR (Azospillum lipoferum (AL) and Bacillus megaterium (BM)) applications, as well as post-harvest dipping with melatonin (0.05 and 1 mM) applications. On the 12th day of mycelial development, Azospillum lipoferum (AL) and Bacillus megaterium (BM) bacteria were inoculated into the compost at a rate of 3 mL per 0.5 L of water per m2 . As a control environment, only 0.5 mL of water was applied to the compost without bacterial inoculation. Subsequently, mushrooms (Agaricus bisporus) harvested at the same maturity were dipped into melatonin solutions and stored in a cold storage at 0°C and 90-95% humidity for 16 days. At 4-day intervals during harvest and storage in the cold storage, weight loss, color (L*, C˚, and H˚), total phenolic (TF) content, antioxidant activity, respiration rate, and internal gas components were determined. The application of melatonin to mushrooms during post-harvest storage showed positive effects on weight loss and color preservation, reduction of respiration rate and internal CO2 in packaging, and increase in total phenolic and total antioxidant content. These effects were observed to preserve cap quality for 16 days. These findings indicate that combined applications of PGPR and melatonin are considered a promising method to improve the post-harvest quality of mushrooms.