Identification and characterization of Pestalotiopsis spp. causing leaf spot and leaf blight on jabon (Neolamarckia spp.) in Indonesia

Abstract

Abstract. Herliyana EN, Oktavianto P, Siregar UJ. 2022. Identification and characterization of Pestalotiopsis spp. causing leaf spot and leaf blight on jabon (Neolamarckia spp.) in Indonesia. Biodiversitas 23: 6547-6556. Jabon (Neolamarckia spp.) is one of the fast-growing trees with high economic value for industrial plantations. Its monoculture planting system is faced with certain problems, such as the leaf spot and leaf blight diseases caused by Pestalotiopsis sp. Therefore, the aim of this research was to describe the morphology of Pestalotiopsis species through macroscopic and microscopic observations, followed by the identification of fungus using DNA barcoding causing leaf spot and leaf blight on the tree. A total of 11 Pestalotiopsis isolates were used for this research. The morphology was identified by observing mycelium colonies and fungal conidia, while DNA barcoding was initiated after DNA isolation using cetyltrimethylammonium bromide (CTAB) method, amplification with ITS 1 and 4 primers, followed by sequencing process. The results of DNA barcoding showed that 5 species of Pestalotiopsis, namely Pseudopestalotiopsis theae, Pestalotiopsis microspora, Pestalotiopsis palmarum, Neopestalotiopsis clavispora, and Pestalotiopsis virgatula were found associated with leaf spot and blight disease. All the five species were further classified into 3 clades using phylogeny according to their median cells and apical appendage shape. The clade X consisted of P. palmarum, N. clavispora, and P. virgatula with versicolorous median cells, whereas clade Y included P. microspora with concolorous median cell, and clade Z consisted Ps. theae with concolorous median cell and knobbed apical appendage.

Pest categorisation of Pestalotiopsis microspora

“…Pestalotiopsis microspora can cause symptoms on several parts of its host plants. However, it affects mainly the leaves, causing leaf spot (De Jesus et al., 2022 ; Herliyana et al., 2022 ; Shen et al., 2014 ; Yuan et al., 2022 ) and leaf blight (Bhuiyan et al., 2022 ; Herliyana et al., 2022 ; Jeon et al., 2007 ; Jeon & Cheon, 2014 ; Ngobisa et al., 2018 ; Wu et al., 2009 ; Xiao et al., 2016 ; Zhong Jiu et al., 2010 ). It can affect roots, causing root rot (Lu et al., 2016 ), but also fruits, causing fruit spots (Chuanqing et al., 2010 ; Shi et al., 2015 ), scabby fruit canker (Keith et al., 2006 ) and pre‐ (Sultana et al., 2021 ) and post‐harvest fruit rot (Chen, Chen, et al., 2016 ; Li et al., 2016 ), and to a lesser extent twigs, causing twig blight (Ren et al., 2021 ).…”

“…The conidia are fusiform with four septa, with both the basal and terminal cells being hyaline and the median cells brown (Strobel et al., 1996 ). The conidia vary in size from 18.1 to 35.9 μm long by 4.4 to 6.9 μm wide (Herliyana et al., 2022 ). The first median cell is 3.3–6.6 μm long, the second 3.3–5.7 μm and third 3.6–6.6 μm.…”

“…The apical cell is 3.2–6.1 μm long, hyaline, conic, with two to four tubular apical appendages, arising from the apical crest, unbranched, filiform, and 11.2–35.4 μm long. The basal cell is 2.9–6.4 μm long, conic, hyaline, with a single tubular basal appendage, 3.5–10 μm long, and unbranched (Herliyana et al., 2022 ).…”

“…The molecular techniques available for the identification of P. microspora are mostly based on the sequencing of the internal transcribed spacers (ITS) of genomic rDNA, in particular the region ITS1–5.8S–ITS2 (Bhuiyan et al., 2022 ; De Jesus et al., 2022 ; Herliyana et al., 2022 ; Jeon et al., 2007 ; Jeon & Cheon, 2014 ; Lu et al., 2016 ; Shi et al., 2015 ; Xiao et al., 2016 ; Zhong Jiu et al., 2010 ). Other DNA regions, such as the protein‐coding gene beta‐tubulin ( tub2 ), have been used together with the ITS for a more reliable identification of P. microspora (Li et al., 2016 ; Yuan et al., 2022 ).…”

“… Rubiaceae Jabon Herliyana et al. ( 2022 ) Nymphaea nouchali Nymphaeaceae Red water lily Rajagopal et al. ( 2018 ) Persea americana Lauraceae Avocado Kimaru et al.…”