The heads are 15-50 mm in
diameter with 5-20 mm long ray florets. Two to three capitulae (heads) grow together,
each having ray and disk florets. The receptacle has a semi-spherical shape
and is 1-2 cm in diameter and 0.5-0.8 cm high. The receptacle is surrounded by two
rows of involucral bracts. The capitulum consists of six to eight fertile female ray
florets with narrowly elliptic, obovate ovules. The stigma has two curled branches
about 2 mm long. The hermaphrodite disk florets, usually 40-60 per capitulum, are
arranged in three whorls (Figs. 1.1 and 1.2). The disk florets are yellow to orange
with yellow anthers, and a densely hairy stigma.
The achene is club-shaped, obovoid and narrowly long (Seegeler 1983). The
head produces about 40 fruits. The achenes are black with white to yellow scars on
the top and base and have a hard testa. The embryo is white.
Niger is usually grown on light poor soils with coarse texture (Chavan 1961). It
is either grown as a sole crop or intercropped with other crops. When intercropped
it receives the land preparation and cultivation of the main crop. In Ethiopia it is
mainly cultivated as a sole crop on clay soils and survives on stored moisture. A
more detailed description on the agronomy of niger is presented under Agronomy
The heads are 15-50 mm indiameter with 5-20 mm long ray florets. Two to three capitulae (heads) grow together,each having ray and disk florets. The receptacle has a semi-spherical shapeand is 1-2 cm in diameter and 0.5-0.8 cm high. The receptacle is surrounded by tworows of involucral bracts. The capitulum consists of six to eight fertile female rayflorets with narrowly elliptic, obovate ovules. The stigma has two curled branchesabout 2 mm long. The hermaphrodite disk florets, usually 40-60 per capitulum, arearranged in three whorls (Figs. 1.1 and 1.2). The disk florets are yellow to orangewith yellow anthers, and a densely hairy stigma.The achene is club-shaped, obovoid and narrowly long (Seegeler 1983). Thehead produces about 40 fruits. The achenes are black with white to yellow scars onthe top and base and have a hard testa. The embryo is white.Niger is usually grown on light poor soils with coarse texture (Chavan 1961). Itis either grown as a sole crop or intercropped with other crops. When intercroppedit receives the land preparation and cultivation of the main crop. In Ethiopia it ismainly cultivated as a sole crop on clay soils and survives on stored moisture. Amore detailed description on the agronomy of niger is presented under Agronomy
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