Echinochloa oryzoides (Ard.) Fritsch - Oryzoid Barnyardgrass.
Systematic position.Family Poaceae (Graminea), genus Echinochloa Beauv.
Biological group.Annual plant.
Morphology and biology.Stem 50-150 cm in height, straight, branchy from base, naked, with pubescent lower nodes. Leaves linear-lanceolate, to 1 cm in width, flat, with dense hairs at base of blade; sheaths naked or covered with accumbent hairs; ligule absent. Inflorescence 8-15 cm in length, with rough twigs. Seeds germinate from depth no more than 15 cm. Shoots appear at temperature 15-18°C. Flooding by water up to 15 cm above sprouting seeds does not change their germination ability. Flowering in August and September. Fruiting in September and October. The maximal seed production of one plant is 6000 caryopsides.
Distribution.Southeast Asia; the European part of the CIS, the Caucasus, the Far East, Central Asia.
Ecology.Thermophilic and hygrophilic plant.
Economic significance.Persistent specialized weed of rice, littering grain mainly. Control measures include crop rotation and careful cleaning of seed material. Fallow is effective. It is worth to make 2 or 3 provocative floods by water during the vegetative period to cause seed germination of the weed. After appearance of shoots the deep plowing is worthwhile, with the following drying-out of ground. Lucerne or tilled cultures are good predecessors.
Related references.Komarov V.L. (Ed.). 1934. Flora of the USSR. V.2. Leningrad: AN SSSR. P. 33 (in Russian).
Nikitin V.V. 1957. Weed plants of Turkmenia. Ashkhabad: AN Turk. SSR. P. 214 (in Russian).
Nikitin V.V. 1983. Weed plants of the USSR flora. Leningrad: Nauka. P. 96 (in Russian).
Ul.yanova T.N. 1998. Weed plants in flora of Russia and other countries of the CIS. Saint Petersburg. P. 193 (in Russian).