In this article we will discuss about the diseases management strategies for harvested fruits and vegetables.
Fresh fruits and vegetables are rich in moisture and nutrients, thus susceptible to attack by various pathogenic microorganisms that are incapable to parasitize them during the period of their development and growth. These are attacked by certainly weak pathogens like fungi and bacteria, typical of harvested fruits and vegetables. Post-harvest diseases limit the storage period and marketing life of produce.
The economic loss incurred through storage diseases might exceed that caused by field diseases because of the large investments in the overall treatments and processing of the product i.e., harvesting, sorting, packing, storage and transport undergoes from harvest until it reaches to the consumers. In developing countries Post-harvest losses are even greater due to the lack of adequate refrigeration and poor sanitation.
Worldwide, Post-harvest losses have been estimated to be 50 per cent of the harvested crop and which are mainly due to rots caused by microorganisms. In fact, international agencies that monitor world food resources have acknowledged that one of the most feasible options for meeting future needs is the diminution of Post-harvest losses.
Post-harvest diseases have not received the much attentiveness that the magnitude of crisis necessitates. It is difficult to determine the full extent of Post-harvest losses due to diseases and the losses caused by them remain substantial. Fresh fruits and vegetables supply essential nutrients such as vitamins, minerals, carbohydrates, antioxidants and anticarcinogenic substances which are important to human health.
The rising awareness about the advantages of fresh fruits and vegetables awakens the consumer to prefer the wholesomeness of the fresh produce over processed products. However, at the same time, the demand of consumers for the produce free of pathogen and chemical residues has been growing during recent years. In other words, the safety of fresh produce has become a major public concern today.
The aim of adequate storage is, therefore, to help the harvested fruits and vegetables to reach their destination i.e., fresh, disease free and safe to consumers, despite the complex of treatments they have to undergo prior to or during storage and despite the long period between their harvest and their reaching the consumers.
To understand how decay can be prevented or delayed, be familiar with the cause of decaying, their nature, origin, time and mode of penetrating into the host as well as with the factors that affects their Post-harvest development.
At a later stage be familiar with suitable means of preventing disease initiation or arresting pathogen development within the host tissues and the possibility of maintaining or enhancing host resistance to infection.
Primary means of controlling post-harvest diseases are fungicides and they have recently come under special scrutiny as posing potential risks when applied to processed foods. Even when acceptable fungicides are applied for the management of Post-harvest diseases, pathogens often develop resistance to them.
All these developments weaken our ability to control microorganisms responsible for Post-harvest losses. An urgent need exists for new and effective means of controlling Post-harvest diseases that pose less risk to human health and environment.
The purpose of this review is to inspect the present scientific base, alternative technologies and biological strategies for the management of Post-harvest diseases. Several promising approaches and potentially safer technologies are available for Post-harvest disease control.
The Future Prospects:
The major fungicides used to control Post-harvest diseases of fruits and vegetables might have its residue in treated produce. The available alternatives are refrigeration, sanitation, irradiation, hot water treatments and modified atmospheres have been used effectively to control Post-harvest diseases of fruits and vegetables.
Uses of biological control agents for the management of Post-harvest diseases of fruits and vegetables to meet this need are not biological, but rather economic and social. Biological control of Post-harvest diseases appears to hold greater promise than other diseases controlling methods of field crops.
The economic advantage of a fungicide over a biological becomes an unresolved point if that particular fungicide is withdrawn from the market and there are no effective chemical alternatives.
Current economic assessments of biological control procedures may therefore, change radically in response to the withdrawal of certain fungicides. Social values in regard to pesticides have growing concern over pollution of our environment and ill-effect on human health.
The challenge for plant pathologists is to take this opportunity for the advancement of biological control measures as a viable alternative to fungicides for the disease management of matured fruits and vegetables.
Few opportunities are available to meet a critical need in improving food production technology and boosting the quality of the food. Biological control measures are better possibility for the management of Post-harvest diseases of fruits and vegetables as an alternative to fungicides.
Exploration of natural plant products as fungicides, biocontrol agents and defense strategies in harvested commodities reveals a multitude of new approaches for control of Post-harvest diseases will be as effective as fungicides and presumably safer for man and the environment.