Caracterização morfológica do banco ativo de germoplasma de batata da Embrapa

Abstract

Currently, the area cultivated with potatoes in Brazil is of 117 thousand hectares, with 65% of production in the high-altitude tropical region and 35% in the subtropical region. The main cultivars planted in the country are mostly of foreign origin and present several problems when cultivated in the national climate and soil. In this sense, the development of cultivars adapted to Brazilian conditions is essential to guarantee the competitiveness and sustainability of the Brazilian potato chain. Genetic improvement depends directly on the genetic variability available to breeders. A germplasm to be available for use it should be characterized. In this sense, the present work aimed to know the genetic variability conserved in Embrapa's potato genebank based on morpho-agronomic traits of interest for the development of cultivars for different market segments. The experiment was carried out in a greenhouse, at Embrapa Clima Temperado, in the spring/summer 2020 and autumn/winter 2021 seasons. In total, 353 accessions of potato (Solanum tuberosum) from the genebank were evaluated. The traits evaluated were: number of stems, leaf area, shoot dry weight, total number of tubers, tuber fresh weight, tuber shape, skin color, skin roughness, tuber flesh color, tuber length, tuber width, days to start sprouting and length of the apical bud. Using mixed models, heritabilities and genotypic values were estimated for each accession, for each trait analyzed. Principal component analysis as well as correlation analysis were performed. All the variables evaluated showed a wide range of variation and the heritability ranged from medium to high. Correlations among traits ranged from weak to medium and the analysis of principal components revealed great variability in the germplasm. The results obtained indicate that the evaluated germplasm has a good representation of the genetic variability for the analyzed traits. However, some categories are better represented, and others, although present in the genebank, require a greater representativeness of accessions.