GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Panicum

HABIT Annual (132), or perennial (340). Rhizomes absent (395), or short (42), or elongated (27). Stolons absent (452), or present (15). Culms erect (201/365), or geniculately ascending (103/365), or decumbent (93/365), or prostrate (12/365), or rambling (48/365), or arching (1/365), or leaning (4/365), or scandent (4/365); reed-like (1/112), or robust (25/112), or of moderate stature (2/112), or slender (74/112), or weak (14/112); 1–77.45–1550 cm long; spongy (5), or compressible (5), or firm (418), or wiry (30), or woody (7); without nodal roots (17/100), or with prop roots (2/100), or rooting from lower nodes (98/100). Culm-internodes similar in length (1/5), or shorter and closely spaced at top of culm (1/5), or unequal, the upper longer (1/5), or unequal, the lower longer (1/5), or alternately elongated and bunched (1/5); terete (27/42), or channelled (2/42), or elliptical in section (15/42). Culm-nodes constricted (23/30), or flush with internodes (1/30), or swollen (6/30). Lateral branches lacking (57/209), or sparse (53/209), or ample (110/209), or fastigiate (9/209), or suffrutescent (4/209). Leaves differentiated into sheath and blade (450), or without demarcation between sheath and blade (12), or with sheath almost obsolete (1). Leaf-sheath auricles absent (458), or erect (6). Ligule an eciliate membrane (58), or a ciliolate membrane (72), or a ciliate membrane (253), or a fringe of hairs (68), or absent (23). Leaf-blade base without a false petiole (449), or with a brief petiole-like connection to sheath (12), or with a false petiole (3). Leaf-blades persistent (459), or deciduous at the ligule (5); aciculate (3), or filiform (12), or linear (284), or lanceolate (215), or elliptic (5), or oblong (8), or ovate (25), or triangular (1); membranous (16), or herbaceous (435), or coriaceous (13); stiff (49), or firm (406), or flaccid (10). Leaf-blade midrib indistinct (9/33), or evident (6/33), or conspicuous (16/33), or widened (2/33). Leaf-blade venation without cross veins (444), or with obscure cross veins (6), or with distinct cross veins (17). Leaf-blade margins cartilaginous (14/14). Leaf-blade apex muticous (435), or pungent (30).

INFLORESCENCE Synflorescence simple (462), or compound (1); fasciculate (1/1). Inflorescence a panicle (444), or composed of racemes (16), or comprising only a few spikelets (4); terminal (421), or terminal and axillary (43); not deciduous as a whole (458/462), or deciduous as a whole (4/462); subtended by an unspecialized leaf-sheath (461), or an inflated leaf-sheath (1), or a spatheole (1); exserted (440), or embraced at base by subtending leaf (32), or enclosed (1). Spatheole lanceolate (1/1). Peduncle persistent (461), or fracturing (2).

Panicle open (417/442), or contracted (26/442), or spiciform (7/442), or capitate (1/442). Primary panicle branches not whorled (419/443), or whorled at lower nodes (22/443), or whorled at most nodes (8/443). Panicle axis bearing persistent branches (443/444), or deciduous branches (1/444).

Racemes single (1/16), or borne along a central axis (16/16); appressed (1/16), or ascending (13/16), or spreading (1/16), or drooping (1/16); unilateral (13/14), or paucilateral (1/14); bearing 1–8 fertile spikelets on each (1/1). Central inflorescence axis unspecialized (15/16), or flattened (1/16). Rhachis angular (7/7). Spikelet packing crowded (2/16), or contiguous (14/16); 2 -rowed (1/1).

Spikelets appressed (27/32), or ascending (1/32), or spreading (4/32); solitary (433), or in pairs (44), or in threes (2). Fertile spikelets sessile (4/462), or sessile and pedicelled (3/462), or pedicelled (456/462); 1 in the cluster (1/7), or 2 in the cluster (7/7), or 3 in the cluster (1/7). Pedicels filiform (31/47), or oblong (1/47), or clavate (15/47); tip oblique (1/21), or widened (6/21), or discoid (6/21), or cupuliform (8/21).

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets (461/462), or 2 basal sterile florets (1/462); 1 fertile florets (462), or 2 fertile florets (1); without rhachilla extension (459), or with a barren rhachilla extension (6). Spikelets linear (1), or lanceolate (52), or elliptic (175), or oblong (91), or ovate (166), or orbicular (24), or obovate (30), or oblanceolate (3); of unremarkable solid shape (461), or globose (2); laterally compressed (4), or dorsally compressed (459); symmetrical (450), or gibbous (9), or plano-convex (4); 0.7–2.732–9.2 mm long; persistent on plant (2), or falling entire (460), or breaking up at maturity (1); deciduous from the base (457/460), or with the pedicel (1/460), or with accessory branch structures (3/460). Spikelet callus brief (462), or square (1). Rhachilla internodes brief up to lowest fertile floret (398), or elongated between glumes (64), or elongated below proximal fertile floret (2). Rhachilla elongation stout (1/1). Rhachilla internodes definite (1/1). Floret callus brief (457), or evident (6), or elongated (1); without wings (460), or winged (3); with lateral wings (3/3); truncate (1), or obtuse (462).

GLUMES Glumes one the lower absent or obscure (1), or two (462); shorter than spikelet (63/462), or reaching apex of florets (394/462), or exceeding apex of florets (9/462); thinner than fertile lemma; parallel to lemmas (414), or recurved at apex (6), or gaping (48). Lower glume linear (1/462), or lanceolate (38/462), or elliptic (6/462), or oblong (13/462), or ovate (385/462), or orbicular (4/462), or oblate (25/462), or obovate (3/462); not clasping (16/60), or clasping (44/60); not gibbous (460/462), or gibbous (2/462); hyaline (16/462), or membranous (446/462), or herbaceous (1/462); without keels (456/460), or 1-keeled (4/460); 0–3–11 -veined. Lower glume lateral veins absent (107/462), or obscure (19/462), or distinct (352/462), or prominent (7/462), or thickened (2/462); without ribs (375/380), or ribbed (5/380). Lower glume surface smooth (447/462), or asperulous (7/462), or scabrous (6/462), or tuberculate (3/462); without pits (462/462); glabrous (408/462), or puberulous (10/462), or pubescent (30/462), or pilose (29/462), or villous (5/462), or hispid (1/462), or woolly (1/462); without hair tufts (462/462), or with an apical beard (1/462). Lower glume apex entire (458/462), or erose (1/462), or lobed (4/462); 3 -fid (2/2); emarginate (1/447), or truncate (16/447), or obtuse (106/447), or acute (290/447), or acuminate (90/447), or attenuate (1/447), or setaceously attenuate (1/447), or cuspidate (3/447); muticous (453/462), or mucronate (13/462), or awned (5/462). Upper glume lanceolate (24), or elliptic (91), or oblong (31), or ovate (322), or orbicular (3), or obovate (1); not gibbous (462), or gibbous (1); 0.8–1.355–2.5 length of adjacent fertile lemma; membranous (458), or herbaceous (4), or cartilaginous (1); with undifferentiated margins (460), or hyaline margins (3); without keels (458), or 1-keeled (5); wingless (462), or winged on margins (1); 3–7–57 -veined. Upper glume primary vein eciliate (462), or pubescent (1). Upper glume lateral veins without ribs (458), or ribbed (5); without cross-veins (1/3), or transversely connected at apex (2/3), or with cross-veins (1/3). Upper glume surface smooth (436), or asperulous (15), or scabrous (6), or papillose (2), or tuberculate (4), or wrinkled (2), or rugose (1); glabrous (366), or puberulous (27), or pubescent (59), or pilose (39), or hirsute (2), or villous (8), or hispidulous (4), or hispid (2), or woolly (1); with simple hairs (123/136), or tubercle-based hairs (13/136); without hair tufts (462), or with an apical beard (2). Upper glume apex entire (459), or lobed (4); 3–4 -fid (1/2), or 5 -fid (2/2); emarginate (1/451), or truncate (1/451), or obtuse (97/451), or acute (288/451), or acuminate (85/451), or attenuate (2/451), or cuspidate (3/451), or laterally pinched (1/451); muticous (458), or mucronate (6), or awned (4); 1 -awned (4/4).

FLORETS Basal sterile florets male (172/462), or barren (308/462); with palea (323/447), or without significant palea (135/447). Lemma of lower sterile floret lanceolate (23/462), or elliptic (105/462), or oblong (28/462), or ovate (313/462), or orbicular (3/462), or obovate (1/462); 0.95–1.116–1.3 length of fertile lemma; hyaline (2/462), or membranous (456/462), or chartaceous (1/462), or herbaceous (1/462), or scarious (1/462), or cartilaginous (1/462); 3–6–15 -veined; without ribs (460/462), or ribbed (2/462); without grooves (461/462), or sulcate (1/462); truncate (2/435), or obtuse (73/435), or acute (320/435), or acuminate (55/435), or attenuate (1/435), or cuspidate (2/435); muticous (459/462), or mucronate (4/462). Fertile lemma lanceolate (20), or elliptic (229), or oblong (174), or ovate (56), or orbicular (5), or obovate (13); without auricles (462), or thickened on margins at base (1); dorsally compressed (462/462); not gibbous (462), or gibbous (1); chartaceous (20), or cartilaginous (4), or coriaceous (10), or indurate (430); without keel (461/462), or keeled (1/462); wingless (462), or winged on margins (1); 3–4 -veined (2/36), or 5 -veined (17/36), or 6 -veined (3/36), or 7 -veined (20/36), or 8 -veined (1/36), or 9 -veined (3/36). Lemma lateral veins obscure (3/12), or distinct (7/12), or prominent (2/12). Lemma surface smooth (387), or granulose (5), or asperulous (2), or scaberulous (7), or scabrous (1), or papillose (29), or tuberculate (14), or striate (13), or reticulate (4), or punctate (3); unwrinkled (455), or rugulose (4), or rugose (4); without grooves; glabrous (452), or puberulous (3), or pubescent (6), or pilose (3); with simple hairs (10/12), or clavate hairs (2/12); without hair tufts (462), or with basal hair tufts near margin (1). Lemma margins flat (1), or involute (455), or convolute (8); eciliate (455), or ciliate (5), or pubescent (2), or pilose (1). Lemma apex obtuse (176/342), or acute (137/342), or acuminate (10/342), or apiculate (24/342), or rostrate (2/342); without ornament (419), or laterally pinched (4), or with a little green crest (7), or with a green spot (1), or with a shallow excavation (1), or papillose (1), or scabrous (8), or pubescent (25), or woolly (2); muticous (458), or mucronate (5). Palea embraced by lemma (462), or reflexed at apex (1); not rolled (1), or involute (462); 1 length of lemma; membranous (1), or chartaceous (20), or cartilaginous (3), or coriaceous (10), or indurate (430). Palea surface glabrous (457), or pubescent (2), or pilose (3), or villous (1).

FLOWER Lodicules 2 (7/7); truncate (3/3). Anthers 2 (3/148), or 3 (146/148).

FRUIT Caryopsis with adherent pericarp (181/181); ellipsoid (44/65), or oblong (8/65), or ovoid (12/65), or orbicular (1/65), or obovoid (5/65). Embryo 0.2–0.4095–0.5 length of caryopsis. Hilum punctiform (25/39), or elliptic (14/39).

DISTRIBUTION Europe (6), or Africa (175), or Temperate Asia (27), or Tropical Asia (42), or Australasia (40), or Pacific (26), or North America (108), or South America (198).

Please cite this publication as detailed in How to Cite Version: 27th January 2014.