Two new species of Calonectria (Hypocreales, Nectriaceae) causing Eucalyptus leaf blight in Brazil

Abstract

In recent decades, commercial Eucalyptus plantations have expanded toward the warm and humid regions of northern and northeastern Brazil, where Calonectria leaf blight (CLB) has become the primary fungal leaf disease of this crop. CLB can be caused by different Calonectria species, and previous studies have indicated that Calonectria might have high species diversity in Brazil. During a disease survey conducted in three commercial plantations of Eucalyptus in northeastern Brazil, diseased leaves from Eucalyptus trees with typical symptoms of CLB were collected, and Calonectria fungi were isolated. Based on phylogenetic analyses of six gene regions (act, cmdA, his3, rpb2, tef1, and tub2) and morphological characteristics, two new species of Calonectria were identified. Five isolates were named as C. paragominensissp. nov. and four were named as C. imperatasp. nov. The pathogenicity to Eucalyptus of both species was confirmed by fulfilling the Koch’s postulates.

Soil-borne Calonectria (Hypocreales, Nectriaceae) associated with Eucalyptus plantations in Colombia

“…Calonectria exiguispora, described in this study, has extended the total number of species of the C. candelabrum species complex to 20 (Liu et al 2020;Sanchez-Gonzalez et al 2022). In addition, two previously described species in the C. candelabrum species complex, C. colombiana and C. spathulata, were also found.…”

A Proximal Sensor-Based Approach for Clean, Fast, and Accurate Assessment of the Eucalyptus spp. Nutritional Status and Differentiation of Clones

“…production costs. This greentech approach may be an accurate tool to distinguish symptoms caused by pathogenic agents [ 41 , 42 , 43 ] from those caused by inadequate nutrition in a very rapid way.…”

Molecular and morphological characterization of Calonectria quinqueramosa causing leaf blight on Eucalyptus urophylla in Brazil

“…Based on preliminary isolation yielding Calonectria ‐like morphology fungal isolates, the same procedures used by Sanchez‐Gonzalez et al (2022) were followed for Calonectria isolation and single spore cultures obtainment. The pure cultures were stored and maintained in dry culture and in sterile water (Castellani, 1939), and deposited in the mycological collection of the Laboratory of Forest Pathology at UFLA.…”

“…Based on previous studies (Liu et al, 2021; Liu & Chen, 2017; Wu & Chen, 2021), calmodulin ( cmdA ), histone H3 ( his3 ), translation elongation factor 1‐alpha ( tef1 ), and β‐tubulin ( tub2 ) partial gene regions were used as DNA barcodes to identify Calonectria species. The DNA extraction, and PCR mixture and amplification were performed following the same procedures and conditions used by Sanchez‐Gonzalez et al (2022). The PCR products were separated in a 1.2% agarose gel by electrophoresis at 120 V for 1 h, stained with Diamond Nucleic Acid Dye (Promega) and visualized in an ultraviolet light transilluminator.…”

“…Plant pathogenic fungi belonging to the Calonectria genus have a global distribution and can infect more than 335 different plant species belonging to almost 100 different plant families, including agricultural, horticultural and forestry crops in tropical and subtropical climates (Crous, 2002;). To date, in Brazil have been described 37 species of Calonectria: one mycoparasite species, six were isolated from tropical rainforests (soil samples), seven were isolated from different plant species, and 23 were isolated from diseased tissues or soil samples of Eucalyptus plantations (Crous et al, 2018(Crous et al, , 2019Liu et al, 2020;Sanchez-Gonzalez et al, 2022); all them are distributed in the species complexes of C. brassicae, C. candelabrum, C. cylindrospora, C. gracilipes, C. naviculata, C. pteridis and C. spathiphylli (Crous et al, 2018(Crous et al, , 2019Liu et al, 2020;Sanchez-Gonzalez et al, 2022).…”