Efeito de diferentes fontes nitrogenadas na adubação da cultura da batata (Solanum tuberosum)

Abstract

The potato (Solanum tuberosum L.) due to its high growth rate, high production per unit area and relatively short cycle, is a demanding crop in terms of the presence of nutrients, in the form readily available in the soil solution. When it is properly fertilized with nitrogen, it has a high productive potential. The objective of this work was to evaluate the effect of different nitrogen sources on the fertilization of the potato crop. The present work was carried out in a greenhouse at the Federal University of Fronteira Sul, Campus of Laranjeiras do Sul-PR, located on highway BR-158, Km 405. The soil used as substrate in the experiment was a Dystrophic RED LATOSOL. The experimental design was a completely randomized design (DIC), with 6 forms of nitrogen fertilization, incorporated into the soil, with 6 repetitions per treatment -1, totaling 36 experimental units (pots). The treatments tested were: T1: Control 0% N, T2: NPK 4% N, T3: Extruded poultry bed 2.4% N, T4: Humus 1.1 ± 0.1% N, T5: Bed aviary tanned 2.0 ± 0.2% N, T6: Cattle manure tanned 0.8 ± 0.1% N. The planting of the seed potato was carried out on 05/04/2019, using the cultivar Ágata. Ten days after emergence (DAE), thinning was carried out, leaving only 1 uniform plant-1. At 15 and 30 days after emergencies (DAE), the morphological parameters of the following variables were evaluated for each treatment: plant height (cm), number of nodes per plant (nº plant-1), number of primary and secondary stems (nº plant-1), leaf area index (IAF. In the post-harvest evaluation, all tubers were collected. In the sequence, the number of tubers was quantified and the fresh weight was determined. The data obtained were subjected to analysis of variance (ANOVA) and if there was a significant difference, they were submitted to the Tukey test, at a level of 5% of significance. For the fresh mass variable, the treatment with NPK showed significantly higher values than the other treatments. When analyzing the plant height, the control treatment showed inferior results to the 15 and 30 DAE compared to the other treatments.The variable number of internodes 15 DAE was not different significant difference between treatments. As for the number of internodes 30 DAE, the witness presented values lower than the NPK treatment, extruded aviary bed and tanned aviary bed, not differing from the others. As for the variable number of tubers, the control treatment differed from the NPK treatment, presenting a lower result than this, not differing from the other treatments. Thus, it is evident the need for further studies regarding fertilization with nitrogen sources for potato cultivation.