Microbe Assisted Management of Post-Harvest Horticultural Produce
Author: Dr. Ajinath Dukare
Horticultural Crop Processing Division
ICAR-Central Institute of Post-Harvest Engineering & Technology
Abohar, Punjab, India-152116

Summary
In the area of post-harvest losses management, microorganism finds better application in biocontrol of post-harvest diseases, conversion of fruits and vegetables waste through microbe mediated composting, utilization of these waste as a raw substrate for production of value added products such as bioenergy, single cell protein, organic acids, pigments biopolymer, organic fertilizers and biomass. Thus, tiny microbe could be suitable entities for efficient post-harvest management of horticultural produce

Introduction
Postharvest losses of fruit and vegetables accounts for more than 25% of the total production in industrialized countries and more than 50% in developing countries owing to improper handling and suboptimal storage conditions. In developing countries like India, such losses are even more due to poor cold storage and transportation facilities. Thus, designing environmental friendly strategy for minimizing post-harvest losses and effectual utilization of waste for development of value added products is needed. Utilization of processed waste as substrate for microbial growth and value addition is an alternative green approach. Microorganisms are suitable candidate for recycling and ultimate utilization of horticultural crops processing residues. In this scenario, following are the some areas of work where application of microorganisms could be appropriated to minimize post-harvest losses in concurrent its value addition. These areas are;

Biological control of Post-harvest horticulture crop disease
Post-harvest storage decay losses of fruits and vegetables due to numerous fungal pathogenic species such as Botrytis, Penicillium, Monilinia, Rhizopus, Alternaria, Aspergillus, Fusarium, Geotrichum, Gloeosporium and Mucor are effectively controlled by application of various bioagents. Biological control of postharvest fruit diseases using antagonistic microorganisms like bacteria, yeasts, and fungi has been reported to be an effective and alternative approach, to the use of chemical fungicides. During last few years, several antagonistic microorganisms have been isolated, identified and artificially deployed as biocontrol agents for control of post-harvest diseases on a variety of harvested horticultural commodities including citrus, pome, and stone fruits and vegetables

Losses minimization through value addition of horticultural waste
Large amounts of fruits and vegetables processed waste which are generated annually can be used as raw material for the making of valuable microbe based products such as microbial biopolymer(For e.g. Poly-hydroxybutyric acid), cellular enzymes(amylase, cellulase etc.), biomass (biofertilizers, biopesticides), organic acids, pigments, amino acid, single cell protein, and numerous valuable compounds. These various products have wide range of applications in agriculture, food and pharmaceutical industry.

Horticultural waste to bioenergy
Being rich in polysaccharides (cellulose, hemi-cellulose and lignin), the processing waste materials of fruit and vegetable can be subjected to fermentation for the production of various biofuel such as bioethanol, biodiesel biomethane, and butanol. For example, biogas or biomethane, obtained during anaerobic digestion by the microbial community, is a cheap form of renewable energy and can be used as source of energy in rural areas. Use of various wastes for biogas production not only solves the problem of residual management and indoor pollution, but also reduces dependency on wood as source of fuel. Beside this, raw substrate is also converted into bioethanol by application of the potential microorganisms such as Saccharomyces cerevisiae, and Zymomonas mobilis,

Conversion of fruit and vegetable waste to organic fertilizers
Organic manures can be prepared through microbe mediated anaerobic decomposition and composting of organic material, such as plant material, fruit and vegetable waste and household foodstuffs. This humus like material obtained after composting process can be used as a soil conditioner to increase the organic content of soils. The composting process, which is one of decomposition, depends on upon succession of living microorganisms. Among them, bacteria and fungi are of fundamental importance in composting process.



About Author / Additional Info:
Working as scientist Horticultural Crop Processing Division, ICAR-CIPHET, Abohar, Punjab.