Adubação potássica e desempenho agronômico de cultivares de mandioca de mesa em ambiente de cerrado

Abstract

The objective of this work was to evaluate the performance of sweet cassava cultivars as function of the potassium doses in the agricultural year of 2016/17 and their agronomic behavior in two crops in the Cerrado environment. The researches were carried out in the experimental area of the Federal University of Goiás - Jataí Regional. For the first experiment the cultivars BRS 396, BRS 397, BRS 398, BRS 399, BRS 400, BRS 401 and IAC 576/70 were used, and the doses of 0, 30, 60, 120 kg ha-1 of K 2 O were used. In the second experiment the cultivars BRS 397, BRS 398, BRS 399, BRS 400, BRS 401 and IAC 576/70 were used for two crops 2016/2017 and 2017/2018. The evaluations were carried out after nine months of planting, and the biometric and productive components were analyzed. The two experiments analyzed showed significant interaction among the sources of variation: Cultivars X Doses of K 2 O and Cultivars X Harvests for the variables fresh root mass and fresh shoot mass. It was concluded that the K 2 O doses influenced the vegetative development of sweet cassava cultivars. Sweet cassava cultivars show different productive behavior depending on the K 2 O doses and do not respond to potassium fertilization above the recommended dose for maintenance fertilization. Within the conditions of each crop, the cassava cultivars presented a high root yield, highlighting the BRS 399 that showed stable agronomic behavior in the crops with higher root productivity.