An Overview on Citrus Mal Secco Disease: Approaches and Strategies to Select Tolerant Genotypes in C. limon

Abstract

Citrus is an economically important fruit crop that is seriously afflicted by several biotic stress, caused by both viruses and fungi, thus, new sustainable strategies to manage these diseases are needed. Lemon (Citrus limon (L.) Burm. f) is a tree in the Rutaceae family and after orange and mandarin, is the third most important Citrus species. Lemon fruits contain important bio-compounds and have central role in prevention of diseases of a balanced diet. Among C. limon diseases, "mal secco" is a highly destructive tracheomycotic fungal infection spread over the coasts of the Mediterranean basin and the Black Sea areas. The causal agent is the mitosporic fungus Phoma tracheiphila (Petri) Kantschaveli & Gikachvili (syn. Deuterophoma tracheiphila Petri). The pressure of disease has led to a marked decline of the Mediterranean's lemon crop acreage in the last 30 years. The present review explores the state of art in the struggle against mal secco disease (MSD), summarizing main results obtained from both conventional and unconventional breeding approaches. In addition, the strategies used to study the mechanisms involved in P. tracheiphila/lemon interaction and the results obtained to isolate key genes activates in tolerant genotypes are also described in depth. The overview of emergent approaches and technologies is focused to highlight the progress obtained using advanced lemon-breeding methods and suggest guidelines for future research.

Impacts of huanglongbing on fruit yield and quality and on flushing dynamics of Sicilian lemon trees

“…It is caused by the fungus Phyllosticta citricarpa (McAlpine) Van der Aa, and leads to cosmetic deteriorations and loss of market value of fresh fruits. As a quarantine pest, fruit exportation is severely restricted mainly to the European Union countries ( Truter et al., 2007 ; Migheli et al., 2009 ; Abbate et al., 2019 ; EPPO, 2022 ). HLB is associated with the Gram-negative phloem-limited insect-transmitted bacteria ‘ Candidatus Liberibacter asiaticus’ ( C Las), ‘ Ca .…”

Green solutions and new technologies for sustainable management of fungus and oomycete diseases in the citrus fruit supply chain

“…With time, the plant undergoes a progressive basipetal desiccation of shoots, branches, and trunk, which leads to death of the whole plant (Fig. 1a-c) (Abbate et al 2019;Migheli et al 2009;Nigro et al 2011;Russo et al 2020).…”

A super absorbent polymer containing copper to control Plenodomus tracheiphilus the causative agent of mal secco disease of lemon

“…To be effective, multiple applications are needed ( Migheli et al, 2009 ). However, these kinds of treatments determine concerns related to the long-lasting persistence of copper in the environment, which is then accumulated in the soil and ground-waters, with the consequent toxic effects on plants, animals and soil microbiota, and the contamination of food ( Zhou et al, 2011 ; Tamayo et al, 2016 ; Abbate et al, 2019 ). Therefore, restrictions in the use of copper-based fungicides were introduced by the European Union ( La Torre et al, 2018 ).…”