Chitosan coatings reduce fruit fly (Anastrepha obliqua) infestation and development of the fungus Colletotrichum gloeosporioides in Manila mangoes

Abstract

BACKGROUND Mangoes are tropical fruits appreciated worldwide but are extremely perishable, being susceptible to decay, pest infestation and fungal diseases. Using the flavorful and highly valued ‘Manila’ cultivar, we examined the effect of second‐generation chitosan coatings on shelf‐life, phenolic compound variation, phytohormones, pest infestation by fruit flies (Anastrepha obliqua) and anthracnose disease caused by the fungus Colletotrichum gloeosporioides. RESULTS We observed almost total elimination of A. obliqua eggs with 10 and 20 g L−1 chitosan in diluted acetic acid and a five‐ to sixfold reduction in anthracnose damage. Treatment with 20 g L−1 chitosan also extended the shelf‐life. External (skin) and internal (pulp) discoloration processes were delayed. Fruit firmness was higher when compared with control and acetic acid treatments, and total soluble solids were lower in chitosan‐treated fruit. Targeted and non‐targeted metabolomics analyses on chitosan‐coated fruit identified some phenolic compounds related to the tannin pathway. In addition, abscisic acid and jasmonic acid in the peel were downregulated in chitosan‐coated mango peels. Both phytohormones and phenolic content may explain the reduced susceptibility of mangoes to anthracnose development and A. obliqua egg eclosion or larval development. CONCLUSIONS We conclude that chitosan coatings represent an effective postharvest treatment that significantly reduces anthracnose disease, inhibits A. obliqua egg eclosion and significantly extends ‘Manila’ mango shelf‐life, a key factor currently inhibiting large‐scale commercialization of this valuable fruit. © 2020 Society of Chemical Industry

The Role of Plant Hormones in the Interaction of Colletotrichum Species with Their Host Plants

“…Postharvest treatment of mangoes with chitosan revealed downregulated abscisic acid and jasmonic acid levels in the peels, concomitant with a significantly extended shelf life. An infection experiment with C. gloeosporioides showed that anthracnose lesions were significantly smaller on fruits treated with chitosan compared to ones treated with acetic acid and water [58].…”

Effects of chitosan combined with chitosan-montmorillonite nanocomposites coating on postharvest quality of 'Hom Thong' banana fruit

“…(2007) also found that chitosan presented a potent inhibition of fungal germination and development. This result was the same with the research of Limon et al (2021) where C.…”

“…In addition, chitosan effectively enhanced the activities of chitinase and -1,3-glucanase and retard mango ripening (Jitareerat et al, 2007;Jongsri et al, 2017). Limon et al (2021) found that mango fruit coated with chitosan solution also reduced the size of C.…”

Influence of Mineral Particle Films and Biomaterials on Guava Fruits and Implications for the Oviposition of Anastrepha obliqua (Macquart) (Diptera: Tephritidae)

“…When applied to grapes, chitosan did not inhibit C. capitata but stimulated oviposition by this fruit fly [ 54 ]. Studies conducted after oviposition revealed that chitosan inhibited the development of eggs and larvae of A. ludens and A. obliqua in mangos [ 52 , 77 ].…”