Endophytes: Saviour of apples from post-harvest fungal pathogens

"An apple a day keeps the doctor away" is a customarily used proverb due to various nutritional benefits associated with it. However, the fruit is prone to infestation by fungal pathogens during the post-harvest stage which can lead to significant economic losses. Chemical-based fungicides are the chief solution for reducing the occurrence of these fungal pathogens. There has been a paradigm shift from use of chemical pesticides to biological control-based methods with growing societal concern regarding the use of synthetic chemical pesticides post-harvest produce due to several harmful effects on target and non-target organisms. Employment of endophytes as a biocontrol agent is a potential and promising approach for protecting apple from fungal pathogens at the post-harvest phase as they pose no harmful effects on environment, and human health. Contributing to the same, several studies have been carried out by researchers worldwide at laboratory scale which needs to be summarized, so that the findings can be implemented for in-field practices. Owing to the same, this review addresses the major post-harvest fungal pathogens of apples and encapsulates various studies conducted in last two decades depicting the role of endophytes as an alternative to synthetic chemical-based interventions used in post-harvest management of fruits and vegetables. Further, the mode of actions used by endophytes against phytopathogens, including antibiosis, mycoparasitism, competition for space and nutrients, and induced resistance have also been discussed briefly.