Seleção entre populações F6 de pimenteiras ornamentais (Capsicum annuum L.)

Abstract

Capsicum pepper plants have great genetic diversity, which can be used in breeding programs, being the Capsicum annuum species the most widespread by the characteristics of interest presented. The ornamental pepper ideotype is associated with a small plant, leaves and fruits with different colors. Thus, it is essential to perform morphometric characterization to assist in the selection of genotypes that meet the objectives of ornamental pepper breeding programs and market demands. Therefore, the present work aimed to characterize fifteen populations belonging to the F6 generation of ornamental pepper (C. annuum L.), based on morphoagronomic descriptors, aiming at the selection of genotypes for the development of new strains. The experiment was carried out in a greenhouse in the Plant Biotechnology laboratory of the Center for Agricultural Sciences of the Federal University of Paraíba (CCA / UFPB). Fifteen F6 generation pepper populations were evaluated including the additional controls UFPB77.3 and UFPB134. For the first chapter 28 morphoagronomic descriptors of plants, flowers and fruits proposed by the International Plant Genetic Resources Institute (IPGRI) were used. The completely randomized design was used, with 15 treatments and ten repetitions. Data were subjected to analysis of variance and means were ranked by the Scott- Knott test. Genetic divergence was analyzed using the Tocher method, based on the generalized Mahalanobis distance and canonical variables analysis with graphic accession dispersion. The relative importance of the variables was estimated by the method described by Singh (1981) and by canonical variables. From the evaluated characters, the 15 populations were allocated into seven distinct groups using the Tocher optimization method. Fruit characteristics were the ones that most contributed to genetic divergence. UFPB56.8.24.1, UFPB56.26.33.1 and UFPB55.50.12 .1 populations are recommended for F7 generation selection and advancement due to the presence of desirable characteristics for ornamental pepper plants. From the phenotypic characterization, performed through qualitative descriptors of plants, flowers and fruits, of the individuals of the fifteen populations, whose data were submitted to descriptive statistics, expressed in percentage, it was possible to observe that most of the characters formed two classes, while others presented monomorphism. Again, the highest variability was recorded for fruit color in this generation (F6) when compared to the descriptors of plant and flower, possibly because the generation is already advanced. In this generation it is possible to practice selection to obtain lineages between populations, based on the evaluated characters.