Resposta de duas cultivares de Celosia argentea var. plumosa à aplicação de fertilizante mineral de liberação controlada e diferentes doses de bokashi

Abstract

Brazilian floriculture, a sector with a revenue of R$ 11 billion (IBRAFLOR, 2021), depends on precise nutritional management for the cultivation of ornamental potted plants, such as Celosia argentea. The industry standard is the use of mineral fertilizers, such as controlled-release fertilizers (CRF), which optimize nutrient supply. However, the pursuit of sustainability and the reduction of dependence on synthetic inputs are driving biological alternatives, such as the biofertilizer bokashi. This study aimed to evaluate the effect of different doses of bokashi on the vegetative development and biomass accumulation of two cultivars of C. argentea var. plumosa (‘Kimono Scarlet’ (K.S.) and ‘Castle Orange’ (C.O.)), in comparison to CRF. The experiment was conducted in a completely randomized design (CRD), in a 2 x 6 factorial arrangement (cultivar x doses: 0, 1.7 g CRF, 2.5, 5, 10 and 20 g of bokashi.pot-1), with 14 repetitions, using coconut fiber substrate in 11-inch pots. The variations presented included plant height, stem diameter, flowering size, root length, and fresh and dry masses of the aerial part and root. The data were subjected to ANOVA and regression analysis to determine the dose of maximum technical efficiency (XMET). The analysis of variance showed a significant Dose x Cultivar interaction for most parameters, justifying a separate analysis. For the K.S. cultivar, bokashi proved to be a viable substitute and, in some aspects, superior to the mineral standard. The doses of 10 g and 20 g of bokashi were significantly superior to CRF in stem diameter and equivalent in the accumulation of dry mass of the aerial part. Cubic regression indicated a 10 g dose of bokashi as the XMET for height. For the C.O. cultivar, CRF was significantly superior to bokashi in total dry mass accumulation. However, doses of 10 g and 20 g of bokashi resulted in significantly larger inflorescences than CRF, indicating a positive effect for ornamental purposes. For C.O., it was not possible to determine a reliable XMET due to the inconsistency of the response at the tested doses. It is concluded that the effectiveness of bokashi depends on cultivar constraints. The biofertilizer is a sustainable and efficient alternative for cultivating ‘Kimono Scarlet’, with a dose of 10 g being recommended to maximize its development. For the ‘Castle Orange’ cultivar, CRF is still the most efficient management for total productivity.