Period before interference on cassava crop in the presence and absence of liming

Cassava is one of the main plants grown in Brazil and is generally cultivated by small producers as a subsistence crop, in different types of production systems, as it is a rustic plant with good productivity, however, the competition for nutrients with the Weeds is very harmful to the development of the crop, especially in the period that they remain vegetating together. This work aims to determine the period before interference (PAI) in the cassava culture installed in two planting systems. Thus, the experimental treatments consisted of seven periods in contact with the weeds: 0-25, 0-50, 0-71, 0-91, 0-111, and 138 days after emergence (DAE) and another witness without coexistence with the infesting community. The experimental treatments were arranged in a randomized block design, in four replications. The results showed that 15 and 5 days were the periods before the interference for the planting system with the presence of lime and in the planting system without the presence of lime respectively, when in coexistence with the weeds of the species Eleusine indica, Cyperus laxus, Digitariasp, and Cyperus iria.