Australasian Plant Disease Notes (2023) 18:26 https://doi.org/10.1007/s13314-023-00512-3 and Schuurmans Stekhoven are associated with parasit- ism in culture. Between September and December 2019, samples of soil and tubers of D. cayenensis were collected from felds in Alagoas and Maranhão, and soil and D. alata in Pernambuco (Fig. 1). Nematodes were extracted from these using the methods of Jenkins (1964) and Coolen and D’Herde (1972), respectively. Morphometric characterization was performed on 20 adult female specimens which had been fxed in modifed FAA - 38% formaldehyde, glacial acetic acid, and distilled water, and made into permanent mounts (Jenkins and Taylor 1967). The morphometrics V%, a, b, b’, c and c’ of these specimens were compatible with those of P. zeae (Gonzaga et al. 2016). The stylet averaged 16.9 μm in length; the vulva position was 70.3% of body length; and tail morpho- metrics were c = 17.3 and c’ = 2.1. Total body length aver- aged 600.4 μm, and b was 6.2 and b’ was 3.3 (Fig. 2). The permanent slides of P. zeae were deposited in the Nemato- logical Collection of UFRPE, Recife, Pernambuco, Brazil, with accession numbers CN0033 to CN0035. Genomic DNA was extracted from each individual with the kit AxyPrep Multisource Genomic DNA Mini- prep (Axygen®), according to the protocol described by the producer, and the quality and quantity of DNA were estimated respectively on an agarose gel 0.8% and NanoVueTM (GE Healthcare®). Molecular identifca- tion of specimens from the samples of Pratylenchus CN0033 to CN0035 was performed through amplifca- tion and sequencing of the ITS region using primers Yam (Dioscorea spp., family Dioscoreaceae) is a monocot- yledonous fowering plant, cultivated in Africa, Asia, and South America, estimated to be the fourth most important tuber-bearing plant in the world (Ngo-Ngwe et al. 2014). In Brazil, 250 thousand tons is produced annually, from plantings over 25 thousand hectares (FAO 2020). Most is produced and consumed in the states of Paraíba, Pernam- buco, Alagoas, Sergipe, and Maranhão (Brito et al. 2011), and D.cayenensis and D. alata are mostly grown. However, yam is subject to dry rot caused by Scutellonema bradys (Steiner & LeHew, 1933) Andrássy (1958) and Pratylenchus spp. Dry rot is an important problem for yam production, as it signifcantly reduces yield (Moura 2016). Pratylenchus, also known as root-lesion nematode, is regarded as the third most important plant-parasitic nema- tode for world agriculture (Jones et al. 2013), with a wide geographic distribution and extensive range (Gonzaga et al. 2016). This nematode is disseminated throughout all yam producing regions in Brazil, but until now, only the species P. brachyurus (Godfrey) Filipjev and Schuur- mans Stekhoven and P. cofeae (Zimmermann) Filipjev  Mayara Castro Assunção mayara_castroa@hotmail.com 1 Departamento de Agronomia, Universidade Federal Rural de Pernambuco, Recife, PE, Brazil 2 Departamento de Engenharia Agrícola, Universidade Federal Rural de Pernambuco, Recife, PE, Brazil Abstract The genus Pratylenchus is the most economically important nematode for yam. Samples of tubers and soil of Dioscorea cayenensis and D. alata were collected in states of Brazil. Through morphometric characterization and molecular analysis of the ITS and 28S rDNA regions, the nematode Pratylenchus zeae was identifed. This is the frst report of P. zeae in yam in Brazil. Keywords Root-lesion nematode · Identifcation · Molecular · Morphometric Received: 14 March 2023 / Accepted: 12 July 2023 © The Author(s) under exclusive licence to Australasian Plant Pathology Society Inc. 2023 Pratylenchus zeae in yam, Dioscorea cayenensis and D. alata, in Brazil Mayara Castro Assunção 1  · Francisco Jorge Carlos de Souza Junior 1  · Jaime Corbiniano dos Santos Neto 1  · Arielena Augusta Rodrigues Mello 1  · Liany Regina Bezerra de Oliveira Silva 1  · Rosana Blawid 1  · Elvira Maria Regis Pedrosa 2  · Lilian Margarete Paes Guimarães 1 1 3