Characterization of Alternaria and Colletotrichum Species Associated with Pomegranate (Punica granatum L.) in Maharashtra State of India

Abstract

Fungal pathogens are a major constraint affecting the quality of pomegranate production around the world. Among them, Alternaria and Colletotrichum species cause leaf spot, fruit spot or heart rot (black rot), and fruit rot (anthracnose) or calyx end rot, respectively. Accurate identification of disease-causing fungal species is essential for developing suitable management practices. Therefore, characterization of Alternaria and Colletotrichum isolates representing different geographical regions, predominantly Maharashtra—the Indian hub of pomegranate production and export—was carried out. Fungal isolates could not be identified based on morphological characteristics alone, hence were subjected to multi-gene phylogeny for their accurate identification. Based on a maximum likelihood phylogenetic tree, Alternaria isolates were identified as within the A. alternata species complex and as A. burnsii, while Colletotrichum isolates showed genetic closeness to various species within the C. gloeosporioides species complex. Thus, the current study reports for the first time that, in India, the fruit rots of pomegranate are caused by multiple species and not a single species of Alternaria and Colletotrichum alone. Since different species have different epidemiology and sensitivity toward the commercially available and routinely applied fungicides, the precise knowledge of the diverse species infecting pomegranate, as provided by the current study, is the first step towards devising better management strategies.

First report Calonectria hawksworthii as an aetiological agent of fruit rot of cocoa in Brazil

“…In addition, Ca. hawksworthii causes root rot in Punica granatum in India (Manjunatha et al., 2023).…”

“…For instance, Calonectria folliocola and Calonectria sulawesiensis are currently treated as synonyms of Calonectria hawksworthii (Liu et al., 2020), a lesser‐known species with restricted association with certain plants (e.g. water‐lilies, avocado, eucalyptus and pomegranate) (Liang et al., 2023; Manjunatha et al., 2023; Peerally, 1991; Salgado‐Salazar et al., 2022; Tarigan et al., 2023). Calonectria hawksworthii has recently been reported on Eucalyptus in Indonesia and China, demonstrating that it is an emerging pathogen (Tarigan et al., 2023).…”

Insights into Grape Ripe Rot: A Focus on the Colletotrichum gloeosporioides Species Complex and Its Management Strategies

“…identified to date. The host range of C. viniferum has been expanding, with new hosts identified including strawberry [81], walnut [81,82], chili [83] in China, pomegranate in India [84], and Hopea odorata [85] in Bangladesh.…”

Pomegranate: Postharvest Fungal Diseases and Control

“…In the world, the chief producers are India, China, and Iran which produced 70% of pomegranates [12], although official data are not available. Particularly, Indian production represents 41% of the global trade having 288,000 ha of pomegranate orchards and producing 3,256,000 tons of fruit gathered in the Maharashtra state and in the Solapur district [13]. In India, the most spread cultivars are Bhagwa and Arakta available throughout the year; these pomegranates support export to European, Middle East, and Asian countries, especially during the production gap (December, January, and March) [14].…”

“…Alternariosis is one of the most widespread pomegranate diseases, and these have been reported all over the world: Italy, Israel, Greece, California, Spain, and India. Species involved in Alternaria diseases belong to A. alternata and A. arborescens species-complex, their distribution is about overlapped; in addition, just in India is recorded A. burnsii [13,[25][26][27][28][29]. Although, within this genus conidial morphology is easily recognizable, the sporulation pattern is different among species and/or morphotypes, but intraspecific variability of colony morphology is high (Figure 1C-E).…”