Floristic Composition of Soybean (Glycine max (L.) Metrill)-Weed Ecosystem and Influence of Tillage on Weed Dynamics

Seventeen weed species infested the soybean crop and the most damaging weed species were Echinochloa crusgalli, Cyperus iria, Commelina benghalensis and Euphorbia geniculata. The highest IVI was in case of Echinochloa crusgalli followed by Cyperus iria, In first flush after receiving the first shower under no tillage condition 7 weed species were noted viz., Echinochlua crusgalli, Cyperus iria, Commelina benghalensis, Euphorbia geniculata, Psoralea corylifolia, Justicia diffusa and Digera alternifolia. After receiving one shower and killing the first flush of weeds by one tillage operation almost similar weed species emerged in srcond flush but the population was less. After receiving ihe two showers and killing the two flushes of weeds 15 weed species emerged, amongst these Commelina benghalensis, Euphorbia hirta, Acalypha indica, Indlgofera glandulosa, Alysicarpus lo gifolius, Anotis montholani, Caesulia axillaris and Physalis minima were the new species.