Setaria

Scientific name Setaria viridis (L.) Beauv. It is an annual herb of the family Gramineae. Distributed throughout the country. It mainly harms dry crops such as millet, corn, sorghum, wheat, soybeans, cotton, vegetables, and fruit trees.

Morphological characteristics Caryopsis long oval, flat, 1.3-2.2mm long, 0.7-1mm wide, 0.5-0.8mm thick, light gray-green or yellow-green surface, arranged in a row Pinstripe. Coleoptiphylla broadly lanceolate, purple-red, 2.5–3mm long; first leaf oblong, about 10mm long, 2.5–3mm wide, light green or bright green; second leaf longer, leaf The tongue is a circle of l-2mm long dense pilose. Stems erect or basally geniculate; leaf sheaths lax and stems sheathed pilose. The leaves are flat, 10 to 20 cm long and 0.8 to 1.5 cm wide. The apexes are acuminate, the base is broad and slightly sporeling, and both sides and the edges are bristled with polar continents. Inflorescence panicle closely cylindrical, 2-20cm long, rachis branching, several spikelets per plant, densely globose; spikelets oblong, long 2-2.5mm; ovate ovate, long as small 1/3 of the ear, with 3 veins, internal axillary and lateral lemma and spikelets nearly as long, with 5-7 veins, internal aponeurosis, length 1/2 of the spikelets. At the base of the spikelets are 5-6 bristles, 4 to 12mm long, green, yellow or purple.

Ecological characteristics Annual weeds, germination temperature is suitable for 15-30 °C, 10 °C can also germinate, but the germination rate is low and the emergence of slow, in the soil layer depth of 0-8cm. The emergence of seedlings in early May in Heilongjiang, sustainable until late July, flowering in July-August, seed maturity in August-September, mature seeds must live through winter dormancy before germination. The Shanghai area has emerged in mid- and late April, peaking in late May, and peaking in mid-September and 2-3 generations a year.