Desempenho agronômico de progênies de cubiu M2:3 e M3:4

Abstract

To increase genetic variability, mutations were induced with gamma irradiation over cocona seeds, CUB-08 genotype. Meanwhile the efficiency of this method in cocona breeding has not yet been evaluated. This work aimed to evaluate the agronomic performance of nine M2:3 progenies and twelve M3:4 progenies and select plants in each of these generations. The characteristics evaluated in the M2:3 generation were: stand, number of fruits, average fruit mass, yield per plant (g), yield per hectare, fruit length - L, fruit diameter - D, L/D ratio and pulp thickness of pulp. The selection of individual plants in both generations was carried out based on the visual selection and subsequent morpho-agronomic and physico-chemical characteristics of the fruits. To detect differences between progenies, analysis of variance was performed in both generations. The results showed significant progenies effect in M2:3 for fruit mean mass, yield, length and length/diameter ratio. The P12 progeny had the highest fruit yield=12.44 t ha-1, average fruit mass =146.41 g, oblong fruit shape and pulp thickness =8.24 mm. Thirty-three progenies were selected whose average yield was 8.79 t ha-1 and with resistance to Sclerotium rolfsii. In the M3:4 generation there was also a significant progenies effect for stand, fruit number per plant, and pulp thickness. The P12-3 progeny stood out with fruit yield= 18.20 t ha-1, average fruit mass= 122.04 g, oblong fruit shape, pulp thickness=8.64 mm, ° Brix = 5.49 and hairiness = 2.05. Thirty-three progenies were selected with average fruit yield = 12.49 t ha-1. Therefore, gamma radiation is capable of producing genetic variability between progenies up to the M3:4 generation for stand, fruit number per plant, and pulp thickness. Therefore, it should be perform a genealogical selection for these characters in the next generation.