Produção e qualidade dos frutos de mirtileiros: influência da poda de inverno e aplicação de composto orgânico

Abstract

Blueberry bushes were introduced in the 80's in Brazil, and they are still in the development phase and under searching of an efficient production system. Currently, aged orchards have been empirically managed by producers over the years, in terms of pruning and fertilization. In this way, winter pruning becomes important for plants proper management. In addition, the use of organic compost is an alternative to improve soil quality and to increase orchard production. Taking this into consideration, two experiments were carried out with the objective of studying more efficient management for blueberry production. In both experiments, the design was randomized in blocks, in a 2x4 factorial arrangement, with four replications, and the experimental unit consisted of a plant. In the first experiment, the objective was to evaluate the production and fruit quality of 'Bluegem' and 'Powderblue' blueberries through different intensities of winter pruning: no pruning, moderate pruning, drastic pruning and conventional pruning. During the first productive cycle, pruned plants had larger diameters and average fruit mass, but lower production and number of fruits. In the following year, production was stabilized. Physicochemical parameters were not affected by pruning. Both cultivars responded in the same way to treatments. In relation to the second experiment, the objective was to evaluate the influence on fruit production and quality under the application of organic compost in blueberries from cultivars Bluegem and Powderblue. The following dosages were applied to the soil: T1 - without compost, T2 - 2 kg plant-1 on August 25, T3 - 2 kg plant-1 in a fractional way (half in August and the other half before fruit maturation) and T4 - 1 kg plant-1 in August. The pH increased to dose T4 in 2021/2022. The longitudinal diameter was greater in 'Powderblue' regardless of the dose of organic compost in 2020/2021. In conclusion, winter pruning with different intensities is efficient in aged orchards with an excess of vegetative material. However, it is harmful in the first year in relation to production, and the compost dosages were low to obtain satisfactory results.