Performance of arrowroot ‘Viçosa’ intercropped with sunnhemp

Abstract

The aim of this study was to evaluate the productive performance and starch content of rhizomes from common arrowroot ‘Viçosa’ cultivated in an intercropping with sunnhemp (Crotalaria juncea). A randomized-blocks experimental design with four replicates was adopted. Treatments consisted of three crops of arrowroot intercropped with sunnhemp, with the sunnhemp being harvested at 90, 120, and 150 days after seeding (DAS), plus a control treatment (arrowroot monocrop). At each sunnhemp harvesting time, the length of arrowroot plants, mass and nutrient production by sunnhemp, and incidence of invasive plants were evaluated. At harvesting, in addition to rhizome productivity, nutrients and starch production by the rhizomes were evaluated. The intercropping provided a greater arrowroot plant length and lower incidence of invasive plants in the area. The sunnhemp harvest performed at 90 DAS provided greater productivity of arrowroot rhizomes and starch, with the sunnhemp producing 29.7 t ha-1 of fresh matter, and 120, 18, 127, 46, and 6 kg ha-1 of N, P, K, Ca, and Mg, respectively. For most of these nutrients, the amount exported by the arrowroot rhizome was lower than that produced by the sunnhemp, indicating the possibility of improvements in soil fertility.