Propagação vegetativa de seleções de cambuizeiros Myrciaria Floribunda H. West ex Willd O. Berg

Abstract

Brazil is a country with a vast biological diversity, especially in relation to its flora, and is considered one of the main centers of genetic diversity in fruit species in the world, among which the Myrtaceae family occupies a prominent place, with the largest number of species with food potential. Among the various species belonging to the Myrtaceae family is Myrciaria floribunda (H. West ex Willd.) O. Berg, popularly known as "Cambuí". This is a fruit plant distributed throughout Brazil and, in the state of Alagoas, it occurs naturally in the coastal regions of restingas. As well as having interesting organoleptic characteristics, the species has great nutritional, ornamental and pharmacological potential, due to its high concentration of ascorbic acid, as well as being rich in essential oils. Despite its importance, cultivation on a commercial scale has not yet been achieved, as there is still little information on the vegetative propagation of this fruit tree, which, being an allogamous species, has genetic variability when propagated by seed. The aim of this study was therefore to evaluate methods for the vegetative propagation of Cambuí (Myrciaria floribunda O. Berg), in order to gather technical and scientific information that will generate knowledge about its propagation and contribute to its cultivation. To this end, the work was divided into two chapters. Chapter I aimed to carry out a review to systematize the different vegetative propagation techniques of some important genera within the Myrtaceae family, in order to understand the most recommended techniques for speciesthatstill have scarce information regarding cloning, such as Myrciaria floribunda, based on searches in the main academic research databases. The search took place on the Scielo, Scopus and Web of Science databases, using sets of keywords in English: "Air layering", "Cuttings", "Grafting" and "Micropropagation" associated with the Myrciaria, Myrcia, Plinia and Eugenia genera. After refining and selecting the articles, 58 articles were selected for use in the study. The review showed that, in general, all the cloning methods can be used efficiently for the genera studied, but that they depend on a series of factors, such as the choice of technique used, the characteristics of the biological material, the substrate, the ease of rooting, the growth regulator, the concentration of the regulator and the time of year. Chapter II aimed to establish reliable methods for clonal propagation of elite genotypes from the Active Cambuí Germplasm Bank at the Campus of Engineering and Agrarian Sciences of the Federal University of Alagoas. The cuttings study was carried out using a completely randomized experimental design in a factorial scheme, evaluating different concentrations of indolbutyric acid (0, 2000, 4000 and 6000 mg L-1) and different substrates (Sphagnum, Vermiculite, Sand and Bioplant). For the cuttings experiment, three branch diameters (0.5, 1.0 and 2.0 cm) and four concentrations of indolbutyric acid (0, 2000, 4000 and 6000 mg L-1) were tested in a completely randomized design in a factorial scheme. The grafting method was used (full slit top) and three rootstock diameters were evaluated (3-5 mm; 5-7 mm; 7-9 mm) in a completely randomized experimental design. The results obtained indicate that the grafting method was the most efficient of the methods tested, providing graft set and sprouting. Although they didn't show roots, the methods of cuttings and air layering showed positive responses to rooting, mainly due to the formation of callous and morphogenic tissues. Keywords: cloning; Myrtaceae; phytohormones.