Método genealógico e modelos mistos na seleção de linhas segregantes de Capsicum baccatum var. pendulum.

Abstract

Capsicum baccatum var. pendulum chili peppers, known as ladies finger and cambuci, are greatly appreciated in Brazil, however, few studies related to genetic breeding improvement of this species are described. The aim of this study was to propose a new strategy of driving and selection of segregating lines C. baccatum var. pendulum to give sequence to the breeding program genetic of this species in UENF. Forty five lines F2:3 were obtained from individuals of the F2 generation from the cross between UENF 1616 and UENF 1732, using the pedigree method. The selection in F2 was made using the Mulamba Mock index and taking into consideration the traits of greater length, greater wall thickness, soluble solids content and higher dry fruit, important characters to meet both industry as the fruit in natura market. The lines F2:3 were evaluated under field conditions at a spacing of between 1.0 m and 1.2 m between plants rows with seven plants per line. The parents and one commercial genotype represented by BRS Mari were used as controls. The characteristics evaluated were days to flowering (DFF) and days to fruiting (DFR); plant height (PLH); canopy diameter (CAD); fruits number per plant (FNP); fruit fresh mass (FFM); fruit weight feature (FWF); fruit length (FRL); average fruit diameter (FDM); fruit pericarp thickness (FRT); soluble solid content (SSC); dry fruit mass (DFM) and dry matter content (DMC). The heritability estimate of the progeny mean was high magnitude ranging from 0.68 to 0.88 while the individual narrow sense heritability and additive heritability within the plot were of medium magnitude ranging from 0.23 to 0.46 and 0.15 to 0.43 respectively, except for FWF and MSF had values above 0.50 are considered high magnitude. The accuracy of selection was close to unity indicating high accuracy in selection for all traits. The selection of the 20 best lines for each characteristic was based on the ordering of rows in ascending order for the DFF, DFR, PLH, and CAD features in decreasing order for FNP, FFM, FWF, FRL, FDM, FRT, SSC, DFM and DMR, considering the values predicted additive genetic effect BLUP’S and the new improved average population. In order lines F2:3 were better than those obtained in selecting witnesses for the top positions for most traits. Multivariate analyzes were performed by UPGMA hierarchical clustering from individuals selected via higher estimates "BLUP" for FFM and FWF characteristics. After obtaining the groupings of individuals was possible to select these based on their desirable agronomic characteristics. The results obtained by the use of mixed via REML/BLUP and the multivariate analysis models can constitute a new proposal to select individuals with favorable agronomic traits for several generations in breeding programs autogamous species.