Bromus L. is a genus with about 150 species. These are distributed in north temperate and tropical mountains. Members of this iranotouranian element are distributed in different habitat of Iran. Bromus species are significant weed species some of which are cultivated fodder, hay or pasture. In this study Bromus danthoniae var uniaristata is recorded for the first time from Iran. There are a lot of similarities between Bromus danthoniae Trin. varieties but uniaristata is distinguished by awns of uppermost lemma and spike fragility from others. Three varieties have been recorded in this species for Iran Platue (Bor, 1970). From this only one has been recorded in Iran as B. danthoniae var. danthoniae (Bor, 1970). Scholz (1998) believe that rogersii C.E. Hubb. ex H.Scholz could be found in Iran too.
Bromus danthoniae Trin. ex C.A.Mey. var. uniaristata Melderis, (Fig. 1).
Material examined: Khorassan Province, Birjand town, Khorashad, Jouharchi and Zangoui 12161 FUMH!; Khorassan Province, 42 km after Torbat heydarieh to Gonabad town, 850 m, Jouharchi and Zangoui 13692 FUMH!; Khorassan Province, Torbat heydarieh town, Jungle road, after Mohamadabad village, Jouharchi and Zangoui 14063 FUMH!; Khorassan Province, Khaf city, BandeOzbak village, Jouharchi and Zangoui 14097 FUMH!; Khorassan Province, Khaf city, Alinaghi to Douchahi village, on sand dunes, Jouharchi and Zangoui 14103 FUMH!; Khorassan Province, Gonabad city, Bimargh to Ahangaran village, 400 m, Jouharchi and Zangoui 23003 FUMH! (Fig. 2).
Annual grass with erect culms; 12 cm long. Leaf-sheaths tubular for much of
their length; pubescent. Ligule an eciliate membrane, its apex is denticulated
and in one surface. Leaf-blades 4 cm long; 2 mm wide. Leaf-blade surface pubescent;
hairy on both sides. Leaf-blade apex acuminate. Panicle open; hairless under
inflorescence, ovate; dense; 5.5 cm long; 3 cm wide. Primary panicle branches
simple. Panicle branches scabrous and up to 4 mm. Spikelets solitary. Fertile
spikelets pedicelled, comprising 6-16 fertile florets; with diminished florets
at the apex. Spikelets Elliptic; laterally compressed; 20 mm long; 5-10 mm wide;
breaking up at maturity; disarticulating below each fertile floret. Glumes persistent;
unequal; shorter than spikelet. Lower glume lanceolate; 4-5 mm long and 1 mm
width; 1 veined. Lower glume apex acute. Upper glume elliptic; 6-8 mm long and
2-4 mm width; 3-veined. Upper glume apex acute.
||A-Bromus danthoniae var. uniaristata, (a) the
whole plant, (b and c) parts of inflorescence, (d) caryopsis, (e) the dorsal
part of glume, (f) the margins of palea and (g) ligule
||Distribution map of Bromus danthoniae subsp. uniaristata.
In Khorassan Province (North East of Iran)
Fertile lemma elliptic; 7-9 mm long and 1-3 mm width; 5-nerved, chartaceous;
much thinner on margins. Lemma surface pubescent, pilose or villous. Lemma apex
2-fid; awned; awns origin is subapical, upper lemma 3-awned, other 1-awned.
Principal lemma awn dorsal; curved; spreading; up to 15 mm long. Lateral lemma
awns arising dorsally; shorter than principal. Palea shorter than lemma, 4-6
mm long and 1-2 mm width, margins with short hairs; denticalted; 2-awned. Lodicules
2; membranous. Anthers 3; up to 2 mm long. Ovary with a fleshy appendage above
style insertion; pubescent on apex. Caryopsis with adherent pericarp; hairy
at apex; apex fleshy. Hilum linear.
Habitat: Rocky slopes and open lands.
General distribution: Asia-temperate: Soviet Middle Asia, Caucasus, western Asia, Iraq and Arabia. Asia-Tropical: India.