Orobanche cumana Wallroth (1825: 58)

Piwowarczyk, Renata, Pedraja, Óscar Sánchez, Moral, Gonzalo Moreno, Fayvush, George, Zakaryan, Narine, Kartashyan, Nune & Aleksanyan, Alla, 2019, Holoparasitic Orobanchaceae (Cistanche, Diphelypaea, Orobanche, Phelipanche) in Armenia: distribution, habitats, host range and taxonomic problems, Phytotaxa 386 (1), pp. 1-106 : 52-53

3. Orobanche cumana Wallroth (1825: 58) . Type:— RUSSIA (lectotype designated by Tzvelev 1981: 329): “ О. arenaria M. Bieb. In arena mobili ad Wolgam versus Astrachan lecta, 1803” (LE s.n.). Homotypic synonyms:— O. cernua subsp. cumana (Wallr.) Soó (1972: 187) (Turland et al., Art.11.2); O. cernua var. cumana (Wallr.) Beck (1930: 128) ; O. cernua f. cumana (Wallr.) Beck (1890: 143) . Heterotypic synonyms:— O. cernua subsp. parviflora Kotov (1935: 90) ; O. cernua var. bicolor (C.A. Mey.) Reut. in Candolle (1847: 32).

Distribution: —In central (Aragatsotn and Kotayk provinces), rarely in southern (Vayots Dzor and Syunik provinces) and northeastern parts (Tavush province) ( Fig. 35 ).

General distribution: —The natural distribution is from central Asia to southeast Europe where it parasitises Asteraceae sp. ( Artemisia , Xanthium ). It is also a very important parasitic weed on crops (e.g., Helianthus annuus L., Lycopersicon esculentum Mill. and Nicotiana tabacum L.). As a weed, it is present from the southwest to east and southeast of Europe ( Spain and France to Ukraine and Russia), rarely in central Europe (e.g., Hungary and Slovakia), and from there to southwestern Asia (e.g., Iran, Jordan, Turkey and Israel), south Asia (e.g., India and Pakistan), central Asia (e.g., Kazakhstan) and East Asia ( China). Recently this weed has been reported from North Africa ( Tunisia).

Habitat: —Mainly in tobacco plantations.

Hosts: —Known only on Nicotiana tabacum L. ( Solanaceae ).

Phenology: —Flowering (June) September (October), fruiting (August) September–October.

Conservation status: —Least Concern (LC). The species has rather wide distribution in Armenia (4 floristic regions). In many parts of its general range it is a noxious weed of important agricultural fields, infesting crops including mainly tobacco and potato. In Armenia, it needs further observation of its virulence and current monitoring.

Notes: —The taxonomic relationships of Orobanche cernua and O. cumana are unclear as both are very polymorphous species. O. cumana parasitises cultivated plants, mainly Helianthus annuus , rarely Solanum lycopersicum or Nicotiana tabacum , but also, like O. cernua , wild ( Artemisia , Xanthium ) species. In this latter case, the differences between taxa are more subtle; we must remember that the type of O. cumana was collected by Marschall von Bieberstein in Astrakhan province ( Russia) and almost certainly on these wild host-plants, so under these circumstances the plants are usually smaller and with few flowers. It is often included as a variety or taxonomic synonym of O. cernua ( Chater & Webb 1972, Foley 2001), although other researchers recognise it as a separate species. When we study typical individuals, the two taxa differ clearly in host preferences, morphological traits, seed-oil fatty acid profiles ( Pujadas & Thalouarn 1998, Pujadas-Salvà & Velasco 2000), seed morphology ( Plaza et al. 2004) and at the molecular level (e.g., Román et al. 2003, Pineda-Martos et al. 2014 and the references therein). We can also indicate that this taxon, in some cases, has been given different binomials depending on the species that it parasitises (e.g., O. nicotianae Wight (1850: 179) and O. cernua subsp. rajahmundrica Teryokhin (1996: 246) , on tobacco and O. cumana var. helianthi Tzvelev (2015: 214) when it is parasitic sunflower).

It is a serious weed mainly of sunflower, and crop losses exceeding 31% are observed in Moldova, the southern part of Steppe Ukraine, Crimea; Northern Caucasus and southern part of the Volga region; Transcaucasia ( Afonin et al. 2008). The species requires further observation and monitoring in Armenia.

Specimens examined: — ARMENIA. Aragatsotn prov.: Ashtarak distr., Ugan [Ujan], March 1971, O . Ovsenyan ( ERCB); Ashtarak, tobacco plantation, 20 October 1975, Eghiazaryan ( ERCB) ; Kotayk prov.: Kotayk distr., Arinj , tobacco plantation, 19 June 1959, A . Muradyan ( ERCB); Kotayk distr., Avan [actually NE district of Yerevan], [with attached tobacco], 19 July 1965, M . Sarkisyan ( ERCB) ; Syunik prov.: near Meghri , 15 August 1957, B . Bramyan ( ERCB) ; Tavush prov.: Shamshadin distr., Aygedzor , 10 September 1972, T . Saakyan ( ERCB) ; Vayots Dzor prov.: Yeghegnadzor distr., Malishka , 23 September 1972, O . Ovsenyan ( ERCB) .

Figures

FIGURE 35. Distribution of Orobanche cernua (circle) and O. cumana (triangle) in Armenia.