Characterisation of fungal surface contaminants of the Small Maltese June Pear, Pyrus communisvar. bambinella.

Characterisation of fungal surface contaminants of the Small Maltese June Pear, Pyrus communisvar. bambinella.

J Food Prot. 2020 Mar 30;:

Authors: Muscat A, Sardella D, Decelis S, Gougouli M, Koutsoumanis KP, Marín S, Valdramidis V

Abstract
Fungal pathogens cause surface contamination and potential premature fruit spoilage of  Bambinella , a fruit endemic to the Maltese islands, leading to the loss of fruit during the post-harvest phase. The objective of this study was to isolate, quantify and characterise fungal contaminantsof the small Maltese June Pear and describe their growth kinetics.In total, 284 fungicide-free fruits were collected over three consecutive summers (2014, 2015, 2016). The isolated fungi were identified by using forward and reverse colonial morphology.  Species identification was determined by PCR-based methods. The number of colony forming units of each species (CFU) per cm 2 of  Bambinella  outer skin was calculated.Mycelium diameter growth rate studies of the isolates were also carried out at seven different temperatures ranging from 5-35°C.Fungi isolated from  Bambinella  included  Cladosporium ramotenellum , Alternaria arborescens, Penicillium lanosum ,  Penicillium expansum and  Aspergillus sydowii , listed from the most abundant to the least abundant. The Rosso model was fitted to the growth kinetic data and showed that the optimal temperatures for growth of all the five fungi were in the range of 20-22°C, while growth was slower at temperatures below 10°C and above 30°C. As observed in the diameter studies, the order of highest to lowest germination rate was found to be:  P. expansum , A. sydowii ,  P. lanosum ,  C. ramotenellum and  A. arborescens .Germination studies showed that the highest germination rate was observed for  P. lanosum followed by  A. arborescens ,  C. ramotenellum , P. expansum and  A. sydowii  , in descending order. The highest germination lag time was observed by  A. arborescens , followed by  C. ramotenellum , P. expansum, P. lanosum and  A. sydowii , in ascending order.

PMID: 32227249 [PubMed – as supplied by publisher]

Source: Industry