Taxonomic information	Current valid scientific name: Atalodera andina (Golden, Franco, Jatala and Astogaza, 1983) de Souza and Huang, 1994 Synonyms: Thecavermiculatus andinus Golden, Franco, Jatala and Astogaza, 1983 Name used in the EU legislation: – Name used in the Dossier: – Order: Rhabditida Family: Heteroderidae
Group	Nematoda
EPPO code	ATADAN
Regulated status	EU status: No status Non‐ EU: No status
Pest status in Peru	Present, widespread
Pest status in the EU	Absent
Host status on Ullucus tuberosus	Several nematode species are known to be associated with ulluco (Jatala, 1988). Ulluco is recorded as a good host of Atalodera (=Thecavermiculatus) andina.
PRA information	A. andina (round cystoid nematode) is a non‐cyst forming heteroderid nematode belonging to the subfamily Ataloderinae. It is an indigenous species in South America where it attacks some important Andean crops. A. andina was first described from oca plants Oxalis tuberosa collected in Peru near Lake Titicaca (Golden et al. 1983). Due to the fact that it multiplies intensively on oca plants and because it is very widespread on farms where this crop is grown, it is commonly known as the ‘nematode of the oca’ (Franco and Mosquera, 1993; Franco and Main, 2008). In addition to oca, ulluco, potato, quinoa, wild quinoa, lupine, Shepherds purse, wild turnip (B. campestris), common groundsel (Senecio vulgaris) and wild tobacco (N. paniculata) are also considered to be effective hosts of A. andina (Franco and Mosquera, 1993). Although the roots of ulluco plants can be heavily attacked with this species information of its economic importance is lacking (Bridge et al., 2005). On the roots of ulluco plants A. andina is often found in association with root‐knot nematodes Meloidogyne spp. and false root‐knot nematode N. aberrans. The life cycle of A. andina consists of egg, four juvenile stages and an adult stage. The eggs spontaneously hatch inside female body at the end of the reproductive cycle and remain there, within the swollen females (Franco and Main, 2008). The first stage juveniles develop within the egg. Second‐stage juveniles (J2) hatch from eggs and after emerging from the female body move through the soil looking for roots of suitable host plant. After finding appropriate host plant, juveniles (J2) penetrate into the host roots inducing multinucleate giant cells – special feeding sites, called syncytium. After undergoing a series of three moults (J3 and J4 juvenile stages), they develop to swollen round–oval females; adult males remain vermiform. Females rupture root cortex and protrude from root surface (Baldwin and Mundo Ocampo, 1991). According to Jatala, A. andina (= T. andinus) is considered an important nematode species of potatoes in some Andean regions of Peru, but crop loss caused by it on potato and other tuber crops has not been adequately quantified (Scurrah et al., 2005). Based on greenhouse experiments, it was found that increasing the population density of A. andina in the soil negatively affects plant development and production of lupine, quinoa, oca and ulluco. This nematode has been reported to reduce quinoa yields significantly (Franco and Main, 2008). Although ulluco and oca can be severely attacked with some economically important plant parasitic nematodes such as N. aberrans, Meloidogyne spp. and A. andina, the control (chemical) of these nematodes is rarely practiced due to the fact that ulluco and oca are grown mainly on economically less important small farms (Bridge et al., 2005). A. andina, therefore, does not pose a major problem in production of these crops. According to Bridge et al. (2005), the response of ulluco to the attack of N. aberrans as well as A. andina indicates the possibility of an available resistant gene base. A. andina has been reported to reduce quinoa yield significantly (Franco and Main, 2008). According to Jatala, A. andina (= T. andinus) is considered an important nematode species of potatoes in some Andean regions of Peru, but information on crop loss caused by it on potato and other tuber crops is lacking (Scurrah et al., 2005). In the answers provided by Peru to the questions raised by the working group, it is stated that SENASA reported attacks of this nematode on potatoes but not on ulluco. It is also stated that A. andina is present in the highlands of the sierra attacking various species of tuberous plants, but its damage is minor. The impact on the ulluco is therefore negligible.
Other relevant information for the assessment
Symptoms	Main type of symptoms	The symptoms caused by A. andina are detected mainly on the roots, on which white spherical female bodies may appear.
	Presence of asymptomatic plants	The absence of symptoms (absence of females bodies in certain plants) is possible; therefore, the presence of A. andina can be overlooked.
	Confusion with other pathogens/pests	A. andina can be misidentified as Globodera spp. by the presence of white spherical females bodies attached to the roots of its host plant (Franco and Main, 2008). However, these females do not change colour nor become cysts (= non cyst forming heteroderid species).
Host plant range	A. andina has a broad host range. It has been reported from more than 30 plant species from 12 botanical families. As suitable hosts are considered: oca (Oxalis tuberosa Mol), quinoa (Chenopodium quinoa Willd), wild quinoa (C. amaranticolor (H.J.Coste & A.Reyn.) H.J.Coste & A.Reyn.), ulluco (Ullucus tuberosus Loz) – fam. Basellaceae, potato (Solanum tuberosum subsp. Andigena Hawkes), wild tobacco (Nicotiana paniculata L.), Shepherd's purse (Capsella bursa‐pastoris L.) and lupin (Lupinus mutabilis Sweet) (Franco and Mosquera, 1993). Other possible hosts (Golden et al., 1983; Franco and Mosquera, 1993): Amaranthaceae: Amaranthus peruvianus Stadley, A. caudatus L.; Cruciferae: Brassica oleracea L. vr. Capitata, B. oleracea L. vr. Botrytis, B. napus, B. campestris L., Raphanus sativus L.; Cactaceae: Cereus geometricus, C. candelabrus, Opuntia sp.; Compositae: Senecio vulgaris L.; Chenopodiaceae: Chenopodium ambrosioides L., Beta vulgaris L.; Leguminosae: Phaseolus vulgaris L., Vicia faba L., Pisum sativum L., Lens esculenta L., Medicago hispida Garth, Trifolium repens L., T. pretense L., T. hybridum L., Medicago sativa L. Labiatae: Salvia sp.; Oxalidaceae: Oxalis solarensis Knuth; Solanaceae: Physalis peruviana L., Lycopersicon pimpinelifolium Mill, L. esculentum Mill, Solanum melongena L.; Tropaeolaceae: Tropaeolum tuberosum R. et P.; Malvaceae: Malvastrum corornandelianum L.
Pathways	– Plants, plants for planting (tubers, roots) – Subterranean plant parts intended for consumption (e.g. edible ulluco tubers) – Soil and growing media as such or attached to plants – Soil and growing media attached to machinery, tools, packaging materials etc.
Surveillance information	– Same as for N. aberrans