Exploitation of Natural Products as an Alternative Strategy to Control Stem End Rot Disease of Mango Fruit in Pakistan

Abstract

Stem end rot (SER) disease development is the major issue affecting the delivery of quality mangoes to distance markets, especially through sea-shipments. Non availability of registered fungicidal products in Pakistan for the management of SER disease of mango is a major hurdle to overcome this enigma. Investigations were carried out to exploit natural products instead of fungicides for the effective management of SER. Fully mature but unripe mango fruits were collected from major mango growing belt of Punjab Province. The fruits were stored in cold storage (12°C; 4-5 weeks) and ambient storage (25°C; 2 weeks). After ripening, fruit under ambient and cold storage revealed that SER was the most prevalent disease. Associated pathogens appeared during ripening were isolated and identified as Lasiodiplodia theobromae, Phomopsis mangiferae, Colletotrichum gloeosporioides, Alternaria alternata, Botrytis cinerea and Cytosphaera mangiferae. In subsequent research, the efficacy of different plant extracts (Cichorium intybus, Peganum harmala, Syzygium aromaticum, Moringa oleifera, Coriandrum sativum and Cinnamomum zeylanicum) at different concentrations was evaluated in vitro and in vivo. Results revealed that M. oliefera, S. aromaticum and C. zeylanicum showed statistically significant antifungal activity against mycelial growth of tested pathogens and SER development.

Stem-end rot in major tropical and sub-tropical fruit species

“…Plant extracts have gained much importance in recent years as safe and effective alternatives to synthetic fungicides. Moringa oleifera, Syzygium aromaticum and Cinnamomum zeylanicum (Alam et al, 2017) extracts of Datura stramonium and Eucalyptus camaldulensis (Ullah et al, 2017), basil oil (Ocimum basilicum), cardamom oil (Elettaria cardamomum) and citronella oil (Cymbopogon nardus L.) (Kulasinghe et al, 2019) have shown significant antifungal activity against mycelial growth of SER pathogens and also a reduction of SER development in mango. Dip treatment of mango fruits cv 'Karuthacolomban' in vivo with cardamom oil in warm water (45 ˚C) significantly reduced SER development with little effect on sensory properties (Kulasinghe et al, 2019).…”

Fruit Stem-End Rot

“…Many studies have revealed the antifungal potential of plant extracts against a range of fungal pathogens [76][77][78]. For example, Moringa oleifera, Syzygium aromaticum and Cinnamomum zeylanicum showed significant antifungal activity against mycelial growth of fungal pathogens that cause SER, and a reduction in SER development in mango fruit [79]. Similarly, a comparative analysis of plant extracts showed that extracts of Datura stramonium and Eucalyptus camaldulensis efficiently reduce the radial growth of Lasiodiplodia isolates in vitro [80].…”

Phytochemical changes in mango fruit in response to Alternaria alternata infection

“…Additionally, postharvest heat therapy (hot air or water treatments and short hot water rinsing and brushing) combined with other treatments could enhance the efficiency of disease management and lead to the attainment of the complete control of decay (Schirra et al 2011). Various fungicides have also been evaluated as chemical methods to control a wide range of postharvest fungal diseases (Adaskaveg & Förster 2010;Alam et al 2017;Perumal et al 2017). In recent years, the Chinese government and Chinese consumers are placing increased emphasis on food quality and safety (Liu et al 2013).…”