Banana bunching associated with climatic and nutritional variations

Choked banana presents closeness of petioles looks that allows the exit of the distal part of the inflorescence, but not the basal part is stuck up at the throat. The aim of this study was to avaluate the effect of choking on the growth of Musa spp. cv Nanica, as well as to investigate how the climatic variations and status nutritional of plants are associated whith this physiological disorder. The experiment was conducted in September/2018 in August/2019 in Registro, São Paulo state, Brazil. The experimental design adopted was completely randomized with two treatments and ten repetitions, in sub-divided plots over time (months). The evaluation consisted in determining the intensity of the symptom, number of leaves, plant height, hand number, stalk length, symptoms of nutritional deficiency and other abnormalities, leaf nutrient contents. Plant growth was not impacted by choking, only the hands number in the months of October/2018 and June/2019 to August/2019 (p< 0.05). Choking occurred throughout the year, with a predominance of severe symptoms of April in June due a redução da temperatura e radiation. The twisted fruits, united by fusion of floral parts and with different sizes occurred, respectively, in 21.67, 60.83 and 17.52% of the symptomatic plants, associated with the cool temperature during the differentiation of the female fruit. Choking and abnormalities in the bunch and fruits were associated with Zn deficiency (p< 0.05). The deficiency of Ca at low temperatures, the lower availability of radiation and the high relative humidity were also associated with the choking. The excess of P in the soil, as well, the adverse climatic conditions contributed to the limitation of these nutrients.