ABSTRACT
This study was performed to introduce the allele Bush of commercial cultivars with a bush growth habit into Cucurbita moschata accessions and select the best crossings for production potential and standard fruit shape “Menina Brasileira” through general combining ability (GCA) and specific combining ability (SCA). To determine GCA and SCA, a partial diallel analysis was performed. The parental group (group I) consisted of two cultivars containing the dwarfism bush gene, and the second group (Group II), formed by five accessions of UFV Vegetable Germplasm Bank, with high production potential and fruit shape “Menina Brasileira”. We evaluated: productivity (PROD), fruit shape (FORM), growth rate until the 50th day after transplanting (CRESC), and length of the main stem on the 50th day (COMP). Significant differences were noticed for CRESC and COMP only between GCA of parents belonging to group I, in which Zapallo stood out. For PROD and FORM, diallel analysis proved to be efficient in studying GCA effects. Cultivar Piramoita (group I) and accessions BGH-4360 and BGH-5253 (group II) showed positive values for GCA, suggesting that these parents possess a higher frequency of favorable alleles for these two traits. Significance in SCA effects was also verified, highlighting the crossing Piramoita x BGH-4360, for PROD, indicating that this combination is the most promising for breeding purposes.
Keywords:
Cucurbita moschata; plant architecture; “bush type”; genetic resources; vegetable breeding