Molecular Characterization of Isolates of Fusarium spp . Associated With Wilt in Capsicum spp .

Fusarium is a diverse and heterogeneous fungi genus. Its wide genetic variability and similarity in morphological characteristics hinder the identification of species of this genus. Identifying Fusarium species is difficult due to the genus. Several molecular methods have been useful for differentiating these species, and the amplification of internal transcribed spacer (ITS) regions of the fungus ribosomal DNA has been successfully used, since ITS are preserved regions of the DNA that assists in distinguishing species. The objective of this work was to collect and characterize isolates of Fusarium spp. associated with wilt symptoms in Capsicum spp. in the biomes of the state of Mato Grosso, Brazil. Were collected tissue samples of plants with wilt symptoms. The DNAs of the Fusarium spp. found were extracted, and subjected to polymerase chain reaction, using the primers ITS1 (5’TCCGTAGGTGAACCTGCGG-3’) and ITS4 (5’-TCCTCCGCTTATTGATATGC-3’). Subsequently, the sequencing was performed. The resulting sequences were, five Fusarium species were found F. solani, F. oxysporum, F. equiseti, F. incarnatum, F. chlamydosporum, predominating F. solani and F. equiseti.


Introduction
Fusarium is a diverse and heterogeneous fungi genus that is important in the food and drug industry, medicine, and agriculture (Luginbuhl, 2010).Fusarium species are worldwide spread; thus, this species have greater genetic, and pathogenic variability (Gonçalves, 2015).They are also known for their ability to cause several diseases in diverse hosts (Summerell et al., 2003).
Several pathogens cause wilt in Capsicum spp.(Ochoa & Ramirez, 2001;Naik et al., 2008;Singh et al., 2017), however, wilt caused by Fusarium, especially Fusarium solani and Fusarium oxysporum, is the main disease in peppers and chilies, and a serious problem for these crops in the last years (Raghu et al., 2016;Tembhurne et al., 2017).
One of the predominant characteristics of Fusarium species is the formation of asexual spores-macroconidia and microconidia (Teixeira, 2015).They also produce resistance structures called chlamydospores (Bedendo, 1995), which assures their survival in plant and soil debris for many years and makes their control and eradication difficult (Raghu et al., 2016;El Kichaoui et al., 2017).
Identifying Fusarium species is difficult due to the genus amplitude and the lack of tools for a reliable differentiation of these species (Lievens et al., 2008).Moreover, distinguishing its species, formae speciales, and races is complicated, even for specialists (O'Donnell et al., 1998;Windels, 1991).However, several molecular methods have been useful for differentiating these species (Kistler et al., 1987).The amplification of internal transcribed spacer (ITS) regions of the fungus ribosomal DNA (rDNA) has been successfully used for this purpose (Hillis & Dixon, 1991;Menezes et al., 2010), since ITS are preserved regions of the DNA that assists in distinguishing species (Chen, 2004).ITS is located between the 18SrDNA and 28SrDNA genes, and this region can be divided into ITS1 (genes 18S to 5.8S) and ITS2 (genes 5.8S to 28S) (Hillis & Dixon, 1991).Amplification of ITS regions is indicated for distinguishing species or varieties, because they are rapidly evolving regions (Fungaro, 2000).Thus, the symptoms genetic var

Study
The morph Laboratory of the isola Molecular Brazil.

Eighty-nin characteris Fusarium
The A first report of occurrence of the pathogen Fusarium incarnatum in C. annuum plants in Trinidad and Tobago named the disease as pepper rot, since it was found in fruits of this crop and caused necrotic lesions (Ramdial et al., 2016).Plants with F. incarnatum presented symptoms of wilting and yellowing.
Fusarium is an important pathogenic fungi genus.It has a conflicting taxonomic history, due to the lack of clear morphological characters separating its species, and its variations and mutations in each host, that end up representing poorly the diversity of Fusarium spp.(Geiser et al., 2004).For example, conflicts in nomenclature are found in the literature; F. incarnatum, F. semitectum and F. pallidoroseum are commonly described as the same species (Leslie & Summerell, 2006).Moreover, Fusarium chlamydosporum, which is found in very few studies, is treated as Fusarium sporotrichioides var.chlamydosporum, and Fusarium fusarioides, according to the Leslie & Summerell Handbook (2006).This species was found in C. annuum seeds in Pakistan (Sharfun-Nahar et al., 2004).

Conclusions
Plants of Capsicum spp. with Fusarium spp.were found in the three biomes of the state of Mato Grosso, Brazil.This is probably the first report on the occurrence of Fusarium spp. in Capsicum spp. in Brazil.Sequencing ITS regions was efficient in differentiating the Fusarium species found.Five species of Fusarium were found in plants of Capsicum spp.: F. solani, F. oxysporum, F. equiseti, F. incarnatum and F. chlamydosporum.
Figure 2. biomes of with Recently the work ofMejía-Batista et al. (2016)found Fusarium equiseti, as well as Fusarium solani, as the causal agent of wilt in Capsicum chinense grown in Mexico.