Reduction of interrow spacing in cassava (Manihot esculenta Crantz) production

The interrow spacing commonly used in cassava cultivation in Brazil, especially in the Agreste region of Alagoas, ranges from 100 to 120cm. However, the reduction in row spacing can provide agronomic and environmental benefits in cassava cropping systems. Thus, this work aimed to evaluate the performance of two cassava varieties cultivated with reduced interrow spacing. Two experiments were conducted in the field, one in 2015/16 and another in 2017/18. A Split Plot design with four replications was used in both experiments. Four interrow spacing were evaluated in the main plot: 60, 80, 100 and 120cm, with plants spaced 60cm apart within rows, giving populations of 27,778, 20,833, 16,667 and 13,889 plants per hectare, respectively. In the subplots, two cassava varieties were evaluated: Caravela and Pretinha. An increase in interrow spacing promoted a linear reduction in the stem green mass of cassava. Plant height, leaf green mass, main stem diameter, root yield, tuberous root length, tuberous root diameter, flour percentage, flour yield, and starch content were not influenced by changes in interrow spacing. The Pretinha variety was superior to Caravela in the following evaluated traits: stem green mass, the diameter of tuberous roots, root yield, plant height, and flour yield. The results indicate the possibility of altering the interrow spacing in cassava to assist in the cultural management, without impacting crop yield.