Adubação potássica com biocarvão da casca do coco verde nos parâmetros de crescimento e na eficiência fotossintética do meloeiro

Abstract

The coconut farming sector generates a large accumulation of waste (husk) from coconut in natura, and to mitigate the negative impacts of discarding these husks on the environment, a strategy has been the conversion of plant biomass into biochar. The application of biochar in the soil increases the availability of nutrients for plants, due to its potential to alter the physical, chemical and biological characteristics of the soil. With this, the objective was to evaluate the effect of the application of biochar from the husk of the green coconut in the fertilization of planting, as a source of potassium in the growth and in the photosynthetic efficiency of the Goldex F1 melon. The experiment was carried out in a greenhouse belonging to the phytotechnics department of the Federal University of Ceará, between the months of December 2022 and February 2023. The design used was completely randomized (DIC), with six treatments in the planting fertilization, according to fertilization recommendation for melon with 20 kg of K2O ha-1, with four replications. The treatments consisted of: T1: without application of biochar and without potassium chloride; T2: 100% of the K2O requirement in the form of potassium chloride; T3: 50% of the K2O requirement in the form of biochar and 50% in the form of potassium chloride; T4: 100% of the K2O requirement in the form of biochar; T5: 125% of the K2O requirement in the form of biochar; T6: 150% of the K2O requirement in the form of biochar. Topdressing fertilization was split throughout the crop cycle, which is mineral and the same for all treatments. Biometric and physiological evaluations were performed during the crop cycle. At the 100% biochar dose, the plants showed greater growth and photosynthetic efficiency.