Introduction: Botrytis cinerea (teleomorph: Botryotinia fuckeliana) is an airborne plant pathogen with a necrotrophic lifestyle attacking over 200 crop hosts worldwide. Although there are fungicides for its control, many classes of fungicides have failed due to its genetic plasticity. It has become an important model for molecular study of necrotrophic fungi. Taxonomy: Kingdom: Fungi, phylum: Ascomycota, subphylum: Pezizomycotina, class: Leotiomycetes, order: Helotiales, family: Sclerotiniaceae, genus: Botryotinia. Host range and symptoms: Over 200 mainly dicotyledonous plant species, including important protein, oil, fibre and horticultural crops, are affected in temperate and subtropical regions. It can cause soft rotting of all aerial plant parts, and rotting of vegetables, fruits and flowers post-harvest to produce prolific grey conidiophores and (macro)conidia typical of the disease. Pathogenicity: B. cinerea produces a range of cell-wall-degrading enzymes, toxins and other low-molecular-weight compounds such as oxalic acid. New evidence suggests that the pathogen triggers the host to induce programmed cell death as an attack strategy. Resistance: There are few examples of robust genetic host resistance, but recent work has identified quantitative trait loci in tomato that offer new approaches for stable polygenic resistance in future.

Botrytis cinerea: the cause of grey mould disease

Listeria monocytogenes is a Gram positive, aerobic, facultative anaerobic and nonacid fast bacterium, which can cause the disease listeriosis in both human and animals. It is widely distributed thoroughout the environment and has been isolated from various plant and animal food products associated with listeriosis outbreaks.

Contaminated ready-to-eat food products such as gravad and cold-smoked salmon and rainbow trout have been associated with human listeriosis in Sweden. The aim of this study was to analyse the occurrence and level of L. monocytogenes in
gravad and cold-smoked salmon (Salmo salar) products packed under vacuum or modified atmosphere from retail outlets in Sweden. Isolated strains were characterized by serotyping and the diversity of the strains within and between
producers were determined with PFGE (Pulsed-field gel electrophoresis). The characterized fish isolates were compared with previously characterized human strains.
L. monocytogenes was isolated from 11 (three manufacturers) of 56 products analysed. This included gravad salmon products from three manufacturers and cold-smoked salmon from one manufacturer. The highest level of L. monocytogenes found was 1500 cfu/g from a cold-smoked salmon product but the level was low (<100 cfu/g) in most of the products. Serovar 1/2a was predominant,
followed by 4b. Three products of gravad salmon harboured more than one serovar. PFGE typing of the 56 salmon isolates detected five Asc I types: four types were identical to human clinical strains with Asc I and one was identical and one was closely related to human clinical strains with Apa I. Isolation of identical or closely related L. monocytogenes strains from human clinical cases of listeriosis and gravad and cold-smoked salmon suggested that these kinds of products are possible sources of listeriosis in Sweden. Therefore, these products should be considered risk products for human listeriosis.

Listeria monocytogenes, a food-borne pathogen

▪ Abstract Losses from postharvest fruit diseases range from 1 to 20 percent in the United States, depending on the commodity. The application of fungicides to fruits after harvest to reduce decay has been increasingly curtailed by the development of pathogen resistance to many key fungicides, the lack of replacement fungicides, negative public perception regarding the safety of pesticides and consequent restrictions on fungicide use. Biological control of postharvest diseases (BCPD) has emerged as an effective alternative. Because wound-invading necrotrophic pathogens are vulnerable to biocontrol, antagonists can be applied directly to the targeted area (fruit wounds), and a single application using existing delivery systems (drenches, line sprayers, on-line dips) can significantly reduce fruit decays. The pioneering biocontrol products BioSave and Aspire were registered by EPA in 1995 for control of postharvest rots of pome and citrus fruit, respectively, and are commercially available. The limitations ...

Biological control of postharvest diseases of fruits.

https://krishi.icar.gov.in/jspui/bitstream/123456789/28711/1/Dr.%20Rajbir%20Singh_Biological%20Control.pdf

Biological control of postharvest diseases of fruits and vegetables by microbial antagonists: A review

Factors influencing the microbial safety of fresh produce: A review

Physical treatments to control postharvest diseases of fresh fruits and vegetables

SummaryThe potential of using essential oils instead of synthetic fungicides to control Penicillium digitatum and P. italicum on citrus fruits was evaluated. The objectives of this study were to determine the antifungal activity of 20 essential oils on colony growth of P. digitatum and P. italicum in vitro and to evaluate their efficacy in vivo by simulating fungicide application in the packing-line or incorporating them into packaging of oranges. In vitro antifungal activity against mycelial growth of P. digitatum and P. italicum was evaluated both by direct contact, and in the vapour phase. Thyme, oregano, clove and cinnamon essential oils completely inhibited P. digitatum and P. italicum growth either when added into the medium at 1000 μl l–1 or by their volatiles with 10 μl per 5 cm diameter Petri dish. In in vivo experiments, none of the oils tested effectively reduced the incidence of P. digitatum and P. italicum on oranges after being applied directly over the inoculated wound at 10, 100 or 1000 μl...

Evaluation of the potential of commercial post-harvest application of essential oils to control citrus decay

Antifungal effect of volatile organic compounds produced by Bacillus amyloliquefaciens CPA-8 against fruit pathogen decays of cherry

Effectiveness of a bacteriophage in reducing Listeria monocytogenes on fresh-cut fruits and fruit juices.

Aims This study compares the effect of temperature (4-37 degrees C) and water activity (aw: 0.99-0.87) and their interactions on the germination rates, lag times prior to germination and mycelial growth 'in vitro' of Penicillium digitatum, P. italicum and Geotrichum candidum, the main postharvest pathogens affecting citrus fruits. Methods and results Germination and growth were markedly influenced by temperature and aw. Generally, lag times were longer and germination and growth rates were slower when conditions of temperature and aw were far from optimum. All the studied species were able to germinate over a range of 4-30 degrees C at 0.995 aw, although in non-optimal conditions P. digitatum only reached 40-60% of germinated conidia. At low temperatures, P. italicum germinated and grew faster than P. digitatum and G. candidum, particularly at 0.95 aw. Penicillium italicum was also able to germinate and grow in the driest studied conditions (0.87 aw), while G. candidum did not germinate under 0.95 aw. Conclusions Knowledge of the ecological requirements of these fungi is important in order to understand their behaviour in natural situations and to predict fungal spoilage on citrus fruits.

https://sfamjournals.onlinelibrary.wiley.com/doi/pdf/10.1046/j.1365-2672.2003.01909.x

Josep Usall

Papers

Physical treatments to control postharvest diseases of fresh fruits and vegetables

Evaluation of the potential of commercial post-harvest application of essential oils to control citrus decay

Antifungal effect of volatile organic compounds produced by Bacillus amyloliquefaciens CPA-8 against fruit pathogen decays of cherry

Effectiveness of a bacteriophage in reducing Listeria monocytogenes on fresh-cut fruits and fruit juices.

Effect of water activity and temperature on germination and growth of Penicillium digitatum, P. italicum and Geotrichum candidum.