Caracterização agronômica de pseudofrutos e cultivo in vitro de híbridos de morangueiro

Abstract

The northern region of Minas Gerais has shown potential for the cultivation of strawberry (Fragaria x ananassa Duch.), Due to the hot and dry climate, which favors phytosanitary management. Hybridization and the development of in vitro propagation systems are fundamental strategies for the production of high quality seedlings. The objectives of this work were to perform the agronomic characterization of 10 hybrids pseudofruits and to micropropagate the superior genotypes in vitro for 5 successive cycles. The hybrids used were obtained from crosses of the varieties 'Aleluia', 'Caminho Real', 'Dover', 'Oso Grande', 'Sweet Charlie' and 'Toyonoka' in the complete dialelo scheme. The following number and fresh mass characteristics of commercial and non-commercial fruits, deformed and undeformed, were evaluated and had better commercial acceptance according to pH, Total Soluble Solids (TSS) and Total Titratable Acid (ATT) values. The selected materials were submitted to micropropagation assays, with multiplication rate evaluations (propagule / explant number in each subculture), number of leaves per propagule and length of shoots. All experiments were plotted in a completely randomized design (DIC), with one plant per plot and 3 replicates. Data were submitted to analysis of variance and the means were compared by the Tukey test, at 5% probability. The OG.AL hybrid was within the group that presented the best values for the desirable phenotypic characteristics among them fresh mass of commercial fruits with means superior to six grams. For the composition of the physico-chemical quality of the fruits, the OG.AL hybrid also presented significantly higher values presenting desirable organoleptic characteristics to the consumer market. In the in vitro culture there was no significant difference between the hybrids but significant differences were observed for the development of the explants in the evaluated subcultures. There was a significant difference in the average number of leaves for the hybrids except CR.SC and in relation to the average size of the propagules falling during the cycles for the hybrids CR.SC and TO.SC. For the OG.AL there was no stable difference and the others differentiated by increasing the size of the propagules.