Produtividade de cultivares de mandioca sobre camalhões em solo hidromórfico com umidade monitorada

Abstract

Cassava culture (Manihot esculenta Crantz) is an important food source for the world population, especially in the poorest regions of the world, and is an excellent option in the fight against global hunger due to its nutritional characteristics. This plant stands out for its great adaptability to different soil and climate conditions. This study aimed to evaluate the productivity and quality of cassava cultivars in hydromorphic soils and subtropical climate. The experimental design used was randomized blocks, with subdivided plots. Two areas were established, area 1 in poorly drained soil and area 2 in well-drained soil. The cassava cultivars used were BRS-399, BRS-429, IAC 576-70, Camanducaia, Mineirinha and Paraguainha, with three replicates. The experiment included three ridges of 22.8 m in length, spaced 1.30 m apart. The plots were 25 m² and subplots of 2.64 m², totaling 134.5 m². Each subplot contained six plants spaced 0.60 m apart. Planting was carried out on 11/16/2023. Fertilization was carried out according to the soil analysis, following the liming and fertilization manual for the states of Rio Grande do Sul and Santa Catarina (2016). Soil moisture was monitored by tensiometers installed at a depth of 30 cm, defining the minimum water tension in the soil at - 0.6 bar. It was found that one area maintained moisture very close to field capacity, oscillating between zero and - 0.3 bar, and another more drained area, oscillating between - 0.2 and - 0.5 bar. Harvesting occurred between 312 and 320 days after planting, observing great root rot in the poorly drained area. The highest productivity in the poorly drained area was obtained by the cultivars Mineirinha (1.31 kg plant-¹) and Paraguainha (0.83 kg plant-¹) and in the well drained area by the cultivars Mineirinha (1.81 kg plant-¹) and IAC 576-70 (1.15 kg plant-¹). Within the quality indicators, the cultivars BRS, IAC and Mineirinha presented easy or medium peeling, cooking time of 16 to 31 min and yellow pulp indicating the presence of carotenoids. The cultivar Camanducaia presents difficult peeling, cooking time of 18 min and white pulp. The cultivar Paraguainha presents medium peeling ease, cooking time of 22 min and white pulp. The soil moisture condition was decisive for productivity, the improved cassava cultivars did not adapt to conditions of high soil humidity, unlike traditional cassava, the result of the selection and conservation work of farmers in their crops for years in a row, which demonstrated greater tolerance to soil with high humidity.