Characteristics of Selected Quality Traits of Novel Cultivars of Pumpkin (Cucurbita Maxima Duch.)

Identification of Fruit-Associated QTLs in Winter Squash (Cucurbita maxima Duchesne) Using Recombinant Inbred Lines

Cucurbita maxima Duchesne squash and pumpkins are cultivated world-wide. Cucurbita maxima fruits are produced for fresh market and are valuable for food processing. Therefore, fruit characteristics and yield are the traits of high economic importance for breeders. To date, the genetic basis of fruit-associated traits in C. maxima have been poorly understood. In the present study, we evaluated fruit-associated traits and conducted quantitative trait locus (QTL) analysis using recombinant inbred lines (RILs) derived from a cross of two inbred lines with different fruit morphotypes. Phenotypic data for nine fruit traits (earliness, weight, number per plant, yield per plant, length and diameter, shape index, flesh thickness, sucrose content and dry matter content) were collected for RILs in two open-field experiments. Pairwise analysis of the phenotypic data revealed correlations among the fruit and yield-associated traits. Using a previously developed genetic map, we identified 26 QTLs for eight traits. The QTLs were found in 10 locations on eight chromosomes of C. maxima. The QTLs were detected across experiments and explained up to 41.4% of the observed phenotypic variations. Major-effect QTLs for multiple fruit-associated traits were clustered on chromosome 4, suggesting that this genomic region has been under selection during diversification and/or domestication of C. maxima.

Evaluation of the Hardness of Pumpkin Pulp Depending on the Implemented Heat Treatment

The work is a compilation of the research results concerning the evaluation of the hardness of pumpkin pulp depending on the implemented methods of heat treatment, i. e. scalding pumpkin in hot water and acting on it with water steam. Extended time of pumpkin heat treatment, both in hot water and combi steamer with steam during 6 min resulted in the reduction of the pulp hardness at 46 % after steaming and 88 % after boiling and softening of the skin, which eased its mechanical removal (cleavage) from the pumpkin fruit. The study was targeted to search for the methods allowing the facilitation and mechanisation of skin removal process in the course of acquiring pumpkin pulp for food purposes.