Chitosan reduces infection by Guignardia citricarpa in postharvest 'Valencia' oranges

Abstract

ABSTRACT

Cowpea resistance induced against Fusarium oxysporum f. sp. tracheiphilum by crustaceous chitosan and by biomass and chitosan obtained from Cunninghamella elegans

“…tracheiphilum during in vitro experiments. Similar results were found by Rappussi et al (2009), Liu et al (2007, 2004 who reported a fungicide effect of chitosan and an inhibitory effect on mycelial growth, morphology, conidia germination and aspersoria formation. In a previous work, the antimicrobial activity of C.eCh, in the same concentrations used in this present study, was evaluated against the mycelial growth of F. oxysporum f. sp.…”

“…The influence of chitosan to increase CAT and POX has been evaluated in tomato plants (Ortega-Ortiz et al, 2007), and to increase POX activity alone in tobacco (Falcón-Rodríguez et al, 2009), in tomato (Liu et al, 2007), in orange fruits (Rappussi et al, 2009) and in cowpea (Rodrigues et al, 2006).…”

Phyllosticta citricarpa and sister species of global importance to Citrus

“…() demonstrated that the combination of standard packhouse fungicide treatments aimed at green mould or sour rot control (including pre‐packhouse drench, packhouse dip and brush application of a wax coating) followed by cold storage (common shipping protocol for exported fresh fruit) consistently showed moderate to high levels of control of CBS in lemons and oranges. Several other studies also reported control of latent P. citricarpa infections through application of various chemical or biological postharvest treatments (Lucon et al ., ; Rappussi et al ., , ; Seberry et al ., ; Yan et al ., ). On the contrary, Agostini et al .…”

“…In addition, the movement of leaf litter from infected orchards through vehicle/ machine movement is also important (Dewdney et al, 2018;Silva-Junior et al, 2016a). Citrus fruit is not considered to be a realistic pathway for spread of P. citricarpa to new areas (USDA APHIS, 2010) for the following reasons: (i) the airborne ascospores cannot be produced on fruit, (ii) pycnidia are only produced in certain fruit lesion types (Brentu et al, 2012;FAO, 2014;Kotzé, 2000;Marques et al, 2012;OEPP/EPPO, 2009;Wager, 1952) and conidia are short-lived with low germination ability (Kiely, 1948b), (iii) conidium dispersal from fruit lesions is by means of short-distance (<1 m) wash-down dispersal (Kiely, 1948b;McOnie, 1965;Spósito et al, 2008Spósito et al, , 2011Whiteside, 1967), (iv) standard packhouse treatments and cold storage effectively control P. citricarpa infections (Korf et al, 2001;Lucon et al, 2010;Rappussi et al, 2009Rappussi et al, , 2011Schreuder et al, 2018;Seberry et al, 1967;Yan et al, 2016), and CBS lesions on fruit or discarded peel segments have a very low reproductive potential (Korf et al, 2001;Schreuder et al, 2018;Schutte et al, 2014), and (v) fallen leaves are not susceptible to infection (Truter et al, 2007). Inter-state movement of commercial packhouse-treated fruit from CBS present to CBS-absent areas is therefore permitted in the USA, in line with their Pest Risk Analysis conclusion that fruit is not a realistic pathway (USDA APHIS, 2011).…”

Antifungal Edible Coatings for Fresh Citrus Fruit: A Review

“…Work in Brazil [86] showed the potential of chitosan coatings to prevent the development of black spot, an important quarantine disease caused by the pathogen Phyllosticta citricarpa (McAlpine) van de Aa, on "Valencia" oranges stored at either 25 °C for eight days or 3 °C for 21 days. The authors discussed that chitosan application stimulated disease resistance mechanisms in the fruit rind.…”