Recurrent selection of pumpkin (Cucurbita moschata) genotypes to increase fruit quality

The aim of pumpkin breeding programs is to develop cultivars that meet the production, commercial quality, and nutritional value, considering several attributes. Therefore, the objective of this study was to select pumpkin genotypes with high fruit quality for future use in genetic breeding programs. Two production cycles were carried out. The evaluations included the determination of genetic parameters (the additive genetic variance, environmental variance between residual variances and individual phenotypic variance, accuracy of progeny selection, restricted heritability, coefficient of individual additive genetic variation, coefficient of genotypic variation between progenies, coefficient of residual variation, coefficient of relative variation, variance of the prediction error of the genotypic values of the progeny), the prediction of genetic gains, and the selection of genotypes with fruits of better physical and chemical quality attributes. The carotenoid and β-carotene contents of the pulp were distinguished by high values of additive genetic variance, residual variance and individual variance. Additionally, genetic gains were achieved for the main carotenoid compounds, as xanthophyll (68%), lycopene (58%) and β-carotene (49%). In the second production cycle, using the technique of Mulamba and Mock, a new ranking method was used to select the best genotypes. These genetic parameters, especially restricted heritability, indicate the potential for advancing new selection stages to develop pumpkin cultivars with superior qualities, including fruit length (0.976), skin thickness (0.951) and orange pigments, particularly β-carotene (0.894). Additionally, firmer fruits with high ascorbic acid content and a pulp hue angle representing an orange color were ranked among the best genotypes.