Cactodera solani n. sp. (Nematoda: Heteroderidae), a new species of cyst-forming nematode parasitising tomato in Mexico

Abstract

Summary A new species of cyst-forming nematode, Cactodera solani n. sp., from Mexico is described. The new species was found in a glasshouse in Mexico City parasitising tomato and common lambsquarter. This cyst nematode has light brown to almost black cysts, presents a small vulval cone with circumfenestra and morphologically it most resembles C. milleri. Cactodera solani n. sp. can be differentiated from C. milleri by having smaller cysts that are 417 (291-581) × 324 (204-505) vs 632 (515-730) × 506 (419-598) μm in size and a longer stylet in the second-stage juveniles of 25 (24-27) vs 22 (21-23) μm. Phylogenetic relationships within populations and species of Cactodera are given based on the analysis of the ITS rRNA and the partial COI gene sequences. The ITS rRNA and COI gene sequences clearly differentiated C. solani n. sp. from other Cactodera species. This new cyst-forming nematode has several generations per year and its life cycle can be completed in 49 days on tomato and in 40 days on common lambsquarter at 20-25°C.

A new cyst-forming nematode, Cactodera tianzhuensis n. sp. (Nematoda:Heteroderinae) from Polygonum viviparum in China with a key to the Genus Cactodera

“…Though few studies on the host-suitability of several species of Cactodera spp. have been evaluated, barley ( Hordeum vulgare L.) is known as being a host for C. galinsogae and C. rosae ( Cid Del Prado and Miranda, 2008 ), and recently described C. solani on tomato ( Solanum lycopersicum ) was reported ( Escobar-Avila et al, 2020 ). In addition, Graney and Bird (1990) performed a host range test of C. milleri including 34 plant species and indicated this species can reproduce on quinoa ( Chenopodium quinoa ).…”

“…In addition, Graney and Bird (1990) performed a host range test of C. milleri including 34 plant species and indicated this species can reproduce on quinoa ( Chenopodium quinoa ). Moreover, three species of Cactodera (namely, C. chenopodiae , C. torreyanae , C. solani ) were shown to be endoparasitic to semi-endoparasitic in sessile habit, a characteristic that the juveniles penetrate with anterior body into the host roots and the posterior body protruding from the surface of the roots ( Cid Del Prado and Subbotin, 2014 ; Escobar-Avila et al, 2020 ; Feng et al, 2018 ). Therefore, the biology, host-suitability, and distribution of Cactodera species (including C. tianzhuensis n.…”

“…The newly obtained sequences for ITS-rDNA and D2-D3 of 28S-rDNA region were compared with known sequences of other related species on GenBank using BlastN homology search program. Outgroup taxa for phylogenetic analyses were selected based on the previously published studies ( Cid Del Prado and Subbotin, 2014 ; Escobar-Avila et al, 2020 ; Feng et al, 2018 ; Soto et al, 2003 ; Subbotin et al, 2006, 2017 ). All the selected sequences were aligned by MAFFT ( Standley, 2013 ) with default parameters and edited using Gblock ( Castresana, 2000 ).…”

“…Up to now, the genus Cactodera contains 16 valid species and mostly parasites plants of Amaranthaceae, Cactaceae, Chenopodiae, and Polygonaceae in different regions ( Escobar-Avila et al, 2020 ; Feng et al, 2018 ; Subbotin et al, 2010 ). To date, very little is known about the occurrence and distribution of Cactodera nematode and only three species of Cactodera have been reported in China: C. cacti (Filipjev and Schuurmans Stekhoven, 1941) Krall and Krall, 1978 parasitizing the roots of Opuntia dillenii ( Pan et al, 1997 ) and Hylocereus undatu ( Duan et al, 2012 ) in Fujian and Liaoning province, respectively; C. thornei ( Golden and Raski, 1977 ) Mulvey and Golden, 1983 was found in cereal fields in Qinghai province ( Peng and Vovlas, 1994 ); C. chenopodiae Feng et al, 2018 was described as a new cyst-forming nematode in the genus Cactodera parasitizing on Chenopodium album in Liaoning province ( Feng et al, 2018 ).…”

Molecular and morphological characterization of a first report of Cactodera torreyanae Cid del Prado Vera & Subbotin, 2014 (Nematoda: Heteroderidae) from Minnesota, the United States of America

“…The newly obtained sequences of the D2-D3 of 28S rRNA, ITS rRNA, COI genes were aligned using ClustalX 1.83 with corresponding published gene sequences ( Cid del Prado Vera and Subbotin, 2014 ; Escobar-Avila et al, 2021 ; Li et al, 2021 ; Skantar et al, 2021 ). Sequence alignment was analyzed with Bayesian inference (BI) using MrBayes 3.1.2 ( Ronquist and Huelsenbeck, 2003 ) under the GTR + G + I model and with PAUP* 4b10 ( Swofford, 2002 ) as described by Subbotin (2021b) .…”