Most Colletotrichum species associated with tree tomato (Solanum betaceum) and mango (Mangifera indica) crops are not host‐specific

Abstract

An important constraint for crop production in Colombia is the high incidence of anthracnose caused by Colletotrichum species. Although several studies have focused on these fungi, the relationship between the different fungal species within the genus and their hosts and whether they display any host preference or host specificity has yet to be examined. In Colombia, diseases caused by Colletotrichum species are particularly severe in mango (Mangifera indica) and tree tomato (Solanum betaceum) crops. In a previous investigation, the Colletotrichum phylogenetic species attacking these crops were identified. The present study aimed to determine whether isolates collected from tree tomato and mango showed host preference or host specificity by assessing aggressiveness, spore density, latent period, and fitness of each strain on the two hosts. In the departments of Cundinamarca and Tolima, Colombia, isolates were collected from plants that presented typical anthracnose symptoms and were identified as C. acutatum, C. asianum, C. boninense, C. gloeosporioides, C. tamarilloi and C. theobromicola. Inoculation of conidia of each isolate onto both hosts showed isolates had no host preference and only the C. gloeosporioides isolate showed host specificity. However, in general, isolates produced a higher spore density when inoculated on the alternate host, which may indicate a difference in the degree of adaptation to each host. Statistical analyses of the assessed parameter values revealed that isolates use different infection strategies when infecting each host. In light of these results, the implications of using quantitative estimations of fitness when studying fungal pathogens are discussed.

Colletotrichum Species Complexes Associated with Crops in Northern South America: A Review

“…In addition, considering that the evaluated species exhibited higher sporulation capacity in alternative hosts, their dissemination capacity might be more related to their survival strategy under adverse conditions, which can allow the fungus to generate a larger number of propagules, rather than host adaptation. These findings support the final analyses of Cabrera et al [65], who state that categorization of Colletotrichum species into generalists and specialists is very simplistic and the reality might be more complex.…”

“…In the reviewed studies, anthracnose and related symptoms were detected in crops from 16 botanical families and 23 species of fruit trees, fodders, ornamentals, leguminous and seasoning plants, and plants intended for industrial use to produce beverages, fibers and oils (Table 2). In fruit plants, attacks by Colletotrichum species have been reported in tree tomato (Solanum betaceum) [21,28,56,65,66], mango (Mangifera indica) [21,28,67], Passiflora (Passiflora edulis) [21,29], strawberry (Fragaria × ananassa) [44,47], blackberry (Rubus glaucus) [23,[30][31][32], plantain (Musa spp.) [36], soursop (Annona muricata) [22,45], avocado (Persea americana) [39,40,43] Tahiti lima (Citrus latifolia) [41,68,69], papaya (Carica papaya) [70], and grape (Vitis vinifera) crops [38].…”

“…Studies of mango and tree tomato crops in Colombia have found that isolates of species belonging to the C. gloeosporioides, C. acutatum, and C. boninense complexes did not exhibit host preference or specificity. Nevertheless, some differences between isolates in terms of their aggressiveness (i.e., ability to cause lesions) and dissemination capacity (i.e., sporulation on the affected tissue) have been observed [65]. This led authors to suggest that the lack of host specificity in these Colletotrichum species may favor the migration of populations from one host to another, which might be a threat to these two crops in Colombia.…”

Colletotrichum truncatum Causing Anthracnose of Tomato (Solanum lycopersicum L.) in Malaysia

“…For microscopic characteristics, the arrangement, shape, and size of acervuli; conidia; conidiogenous cells; appressoria; and setae were examined. Preliminary identification was in accordance with the fungal descriptions of Cabrera et al [ 16 ].…”

Presence of phytopathogenic fungi and oomycetes on rice and avocado crops in Tolima (Colombia)

“…In Colombia, some efforts have been done in order to identify the prevalence and distribution of these pathogens in avocado (Cobo-Nuñez, 2017;Grisales et al, 2016) and others crops such as tomato and mango (Cabrera et al, 2018). As expected, different members of the C. gloeosporioides and C. acutatum were reported for avocado crops in Antioquia.…”