Quo Vadis of Biological Control of Postharvest Diseases

Abstract

Research on Biological Control of Postharvest Diseases (BCPD) has been conducted for over two decades and successes, present and future direction are being discussed. The BCPB has been accepted by the fruit and vegetable industry as the stand alone or in combination with other commercial treatments, depending on fruit and vegetable. BioSave has been on the market since 1996, and its use is expanding to control more postharvest diseases of fruits and vegetables. World-wide efforts in developing BCPD resulted in the registration of more products recently. The number of scientific publications is also increasing steadily. As postharvest biocontrol products are coming to the market, their anticipated limitations are become apparent, and much of the current research is focused on addressing these limitations. Combining antagonists with various substances Generally Regarded as Safe (GRASS), such as sodium bicarbonate, calcium chloride, diluted ethanol, or with physical treatments such as heat, or UV irradiation are typical examples of approaches being used. A mixture of two compatible biocontrol agents often showed an additive or synergistic effect in controlling fruit decays. Biocontrol agents developed for the control of fruit decays have also been shown to inhibit growth of foodborne human pathogens. This aspect gains in importance as new outbreaks are reported with increasing frequency, and fresh cut fruit and vegetables are particularly vulnerable to colonization by foodborne pathogens. Biocontrol agents can also control decays originating from wounds made during mechanical harvesting of fruits. Currently, available biocontrol products were developed for the control of decays originating from the infection of fruit wounds, but the next greatest challenge for BCPD research is the development of the next generation of biocontrol products that control latent infections. Many important diseases of temperate, subtropical and tropical fruit, including those caused by Monillinia spp. and Colletotrichum spp.., originate from these infections in the orchard and cause decay on fruits in storage. This research requires broadening the pool of microorganisms screened for biological control activity to include, in addition to those occurring naturally on fruit, microorganisms from different plants and plant parts, as well as microorganisms from different habitats. Some programs are already focusing in this direction, and there is great hope and optimism that at the next ISPP Congress in 2013 in Beijing, we will have reports on the significant progress in this area.