Fungi Causing Storage Rot of Apple Fruit in Integrated Pest Management System and their Sensitivity to Fungicides

Abstract

Abstract. Apple fruit rot can be caused by several fungi. In Northern Europe, the most common storage rot, Bull's eye rot, is caused by Neofabraea spp., bitter rot by Colletotrichum spp., brown rot by Monilinia fructigena, grey mould is caused by Botrytis cinerea and Fusarium rot by several Fusarium species. Blue mold decay caused by Penicillium expansum is an important disease in several European countries. Incidence of different causal agents may vary depending on cultivar, climate during growing season and agricultural practices. The main objective of the study was to obtain baseline information about apple rot-causing fungi, their incidence during fruit storage and to evaluate the fungicide sensitivity of most of isolated fungal species. The study was performed during the storage period of apples after the growth season of 2013. Rotten apples were sorted in the storage and part of them was brought to the laboratory in order to obtain fungal isolates. Fungi were identified according to the morphological characteristics and sequencing of the ITS1-5.8S-ITS2 region. During storage in February and March the total percentage of rotten apples in various cultivars varied from 3.6 to 58.9%. All post-harvest diseases described in Northern Europe were detected. In part of the storehouses apple rot caused by Cadophora luteo-olivacea was observed. Alternaria spp. and Cladosporium spp. were detected on few apples as secondary infection agents. Using the most often isolated fungal species, sensitivity tests were performed against five commonly used fungicides. In general, the sensitivity of tested fungi to the fungicides was high with exception of several Neofabraea and Alternaria isolates.

Examination of novel Aureobasidium pullulans isolates dominating apple microflora and assessing their potential for apple juice spoilage

“…Moreover, the current study was not focused on the quantitative analysis of each fungal species so there is a chance that there were Penicillium strains among isolates which were not selected for DNA extraction. Other mould found in fruit in the current study— Fusarium, Alternaria and Cladosporium , commonly reside in apple (Bernier et al 1996 ; Grantina-Ievina 2015 ; Abdelfattah et al 2016 ). In the study carried out in Italy, also the presence of M. pulcherrima and some Pichia and Rhodotorula species has been confirmed (Pelliccia et al 2011 ).…”

“…Majority of the research was carried out before molecular methods became commonly available (Williams 1955 ; Pennycook and Newhook 1981 ; Bernier et al 1996 ). Moreover, most studies focused on changes of apple microflora during cold storage of harvested fruits (Mirzwa-Mróz et al 2012 ; Alwakeel 2013 ) or on mould known as common apple pathogens (Grantina-Ievina 2015 ). It has been demonstrated that various fungal species might survive pasteurisation, i.e.…”

Comparison of the occurrence of fungi causing postharvest diseases of apples grown in organic and integrated production systems in orchards in the Czech Republic.

“…Penicillium spp. are frequently isolated from decaying apples as fungi causing postharvest disease (Valiuškaitė et al 2006, Konstantinou et al 2011, Grantina-Ievina 2015, Juhnevica-Radenkova et al 2016. Many researchers (Konstantinou et al 2011, Juhnevica-Radenkova et al 2016 only mention Penicillium expansum, but other species of the genus Penicillium can probably cause postharvest disease of apples, too.…”

“…Other fungal genera causing postharvest disease of apples are investigated less than Neofabraea and Penicillium and therefore less knowledge concerning their diversity is available. Fungi of the genus Alternaria are also frequently recorded as fungi causing postharvest diseases of apples (Valiuškaitė et al 2006, Konstantinou et al 2011, Grantina-Ievina 2015. Konstantinou et al (2011) recorded Alternaria tenuissima on stored apples in Greece, while Grantina-Ievina (2015) isolated A. alternata from apples.…”

“…Many studies focused on the occurrence of fungi causing postharvest diseases of apples have been published from different parts of the world (e.g. Sholberg & Haag 1995, Valiuškaitė et al 2006, Konstantinou et al 2011, Alwakeel 2013, Břrve et al 2013, Grantina-Ievina 2015, Juhnevica-Radenkova et al 2016. Nevertheless, the number of studies comparing the occurrence of fungal species causing postharvest diseases of fruits harvested from organic and integrated apple orchards is very limited.…”