Variability of mango accessions resistance to dieback disease caused by Lasiodiplodia theobromae and Neofusicoccum parvum

Abstract

Mango growing is one of the main agricultural activities in the fruit sector in Brazil for the internal and export market. The crop is subject to damage caused by the fungi Lasiodiplodia theobromae and Neofusicoccum parvum, especially mango dieback disease, which limits the yield and longevity of the mango tree. In spite of the importance of these pathogens, studies regarding sources of resistance in mango are rare. The aim of this study was to evaluate 75 accessions of mango available in the germplasm bank regarding resistance to the fungi L. theobromae and N. parvum to support breeding programs for mango growing. Evaluations were carried out from Apr 2016 to Mar 2018. Conidia suspensions of 10 4 conidia mL -1 of L. theobromae or N. parvum were applied with a manual sprayer on young branches. Accessions were considered resistant when disease symptoms were absent on more than 90% of the branches at three different periods of inoculation. Thirty-three accessions showed resistance to L. theobromae and 19 accessions showed resistance to N. parvum. Six accessions were most susceptible (<50%) to L. theobromae, whereas 25 accessions were most susceptible to N. parvum. The accessions 'Apple DCG', 'Ataulfo', 'Da porta', 'Dashehari', 'Espada', 'Haden', 'Haden 2H', 'Heidi', 'Irwin', 'Keitt', 'Kent', 'Néldica', 'Recife', and 'Smith' showed resistance to the two pathogens and can be used as sources of resistance to the two fungi in mango breeding studies, or these accessions can even be recommended for use as commercial cultivars.

Prevalence of mango postharvest Stem-end rot disease in Cote d’Ivoire and identification of fungal pathogens associated

“…All the SER isolates tested in this study were pathogenic to fruits. Coelho et al, 2020;Netto et al, 2017).…”

“…Lasiodiplodia species might have a high rate of mango inflorescence colonization which could explain the highest isolation percentage. Furthermore, according toCoelho et al (2020) andJi et al (2017), Lasiodiplodia species infect many plant species, including fruit trees, grapevines, ornamental plants, and forest trees. Our results are in agreement with those ofKarunanayake and Adikaram (2020) showing that Lasiodiplodia species are the major pathogens causing SER disease in mango, mainly in the dry and warmer regions of the world.…”