Inventory of fungal pathogens of early maturing Mango varieties in the Kounkane

Introduction

Mango (Mangifera indica L.) is considered one of the most important fruit crops in the tropics. Within the fruit and vegetable sub-group, the mango industry is a promising sector for economic growth. Global mango production is estimated at over 43 million tons (Faostat, 2015). Mango is grown in most West African countries, with an estimated production area of 540,000km², stretching from Senegal throughout to eastern Nigeria according to the Minister of Commerce in 2016 (Ministère du commerce, 2016). Several countries in the subregion, including Senegal, are currently spearheading their export activities (CARE, 2009). In Senegal mango production represents 60% of the country's fruit production, with an estimated annual production of 150,000 tons harvested from a land area of about 41,000 ha (Diedhiou et al., 2014). 

The mango sector is the most dynamic in fruit exports in Senegal (Diouf, 2016). Mango exports have increased from 300 tons in 1998 (Rey, 2011) to 24500 tons in 2021 (Dieye and al., 2021). This performance is due to the modernization of traditional orchards and the creation of new plantations for export. The mango producing orchards are located in the regions of Dakar, Thies, Saint-Louis, Fatick, Kolda, Ziguinchor and Sedhiou (Diedhiou and al., 2014). The soil and climatic conditions and land holdings in the country offer great potential for expanding mango production (USAID-PCE, 2006). The improvement of the mango sector and the implementation of improved technologies along the value chain, offer labor and employment opportunities especially to women and rural youth.

However, mango production, despite a positive record in recent years, is still affected by numerous constraints, including phytosanitary problems. The mango tree is susceptible to host a number of diseases agents at all stages of its development from planting to harvest (Alemu and al., 2014). In the field, mango is most often the host of several pathogens especially fungi that significantly down turn production potential (Khanzada et al., 2004). Diverse fungi cause post-harvest rot of mangoes, with the identity and the incidence of species highly depending on the climatic conditions (Diedhiou et al., 2007). The post-harvest mango rotting can affect up to 100% of mangoes produced during the rainy season in southern Senegal in the absence of adequate control (Diedhiou and al., 2014). Anthracnose due to Colletotrichum gloeosporioides is the almost exclusive causing agents under those conditions while disease incidence is low and results from a diversity of fungi in the Ziguinchor area. Different works have reported various fungi on mango namely Lasiodiplodia theobromae, Colletotrichum spp., Curvularia sp., Pestalotia mangiferae., Alternaria sp. and Fusarium spp. among others (Johnson and al., 1992; Sharma, 1993; Ploetz and al., 1996; Al-Adawi and al., 2003; Dieye and al., 2021). It was therefore important for the mango industry in Senegal to make an inventory of causing agents for mango diseases. This study was conducted with the objective of identifying the fungi responsible for mango diseases in the Kounkane area in southern Senegal during the dry season.