Abstract
In Mexico, the mango crop is affected by anthracnose caused by Colletotrichum species. In the search for environmentally friendly fungicides, chitosan has shown antifungal activity. Therefore, fungal isolates were obtained from plant tissue with anthracnose symptoms from the state of Guerrero in Mexico and identified with the ITS and β-Tub2 genetic markers. Isolates of the Colletotrichum gloeosporioides complex were again identified with the markers ITS, Act, β-Tub2, GADPH, CHS-1, CaM, and ApMat. Commercial chitosan (Aldrich, lot # STBF3282V) was characterized, and its antifungal activity was evaluated on the radial growth of the fungal isolates. The isolated anthracnose-causing species were C. chrysophilum, C. fructicola, C. siamense, and C. musae. Other fungi found were Alternaria sp., Alternaria tenuissima, Fusarium sp., Pestalotiopsis sp., Curvularia lunata, Diaporthe pseudomangiferae, and Epicoccum nigrum. Chitosan showed 78% deacetylation degree and a molecular weight of 32 kDa. Most of the Colletotrichum species and the other identified fungi were susceptible to 1 g L−1 chitosan. However, two C. fructicola isolates were less susceptible to chitosan. Although chitosan has antifungal activity, the interactions between species of the Colletotrichum gloeosporioides complex and their effect on chitosan susceptibility should be studied based on genomic changes with molecular evidence.
Highlights
Diseases caused by phytopathogenic fungi during pre- and post-harvest storage leads to significant losses for farmers and generate conditions for food insecurity [1]
The sequences of internal transcribed spacer (ITS) and β-tubulin 2 (β-Tub2) allowed us to classify the fungal isolates obtained from leaves and fruit into seven main clades consistent of different fungal genera, in which seven isolates belong to the C. gloeosporioides complex, the causal agent of anthracnose in mango (Figure 1)
The second genomic alignment using ITS, Act, β-Tub2, Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), CHS-1, CaM, and ApMat sequences from the isolates of the Colletotrichum complex, allowed the identification of four species of the Colletotrichum genera (Figure 2)
Summary
Diseases caused by phytopathogenic fungi during pre- and post-harvest storage leads to significant losses for farmers and generate conditions for food insecurity [1]. Some of the disadvantages of using these products are the resilience that fungi may develop [5], the damage to health, and damage to the environment [6]. This highlights the need to control post and pre-harvest diseases caused by phytopathogens with compounds that contribute to the success of sustainable agriculture and reduce the use of harmful agrochemicals [7]. The development of alternatives to traditional fungicides aims to reduce environmentally harmful products to control phytopathogenic fungi [8] In this regard, some compounds of natural origin, such as essential oils, methanolic extracts, plant extracts, lipoproteins, and chitosan, have shown antifungal effects [7,9,10]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
