Evaluation of Agro-Morphological Variation in Some Elite Summer Squash (Cucurbita pepo L.) Lines

Cucurbita pepo L., belonging to the Cucurbitaceae family, is an important species with high economic value. This study was carried out within the framework of university and industry cooperation. The genetic material of the researcher consists of 113 elite summer squash (Cucurbita pepo L.) lines selected based on morphological characterisation studies conducted on the company's existing genetic resources. At the end of the study, hierarchical clustering, principal component, and correlation analyses were performed using data from thirty-five quantitative and qualitative traits of fifty selected elite lines to reveal the relationships among the traits. As a result of the clustering analysis, the distance range among the lines varied between 1.52 and 10.98, and the average coefficient of the resulting dendrogram (similarity average) was determined as 0.638. Additionally, it was found that the lines formed two main groups and seven subgroups. Group A includes a total of forty-two lines. In group B, there are eight lines. As a result of the basic component analysis, seven independent principal component axes among the plants were obtained, and these axes explain 70.23% of the total variation in the pumpkin population. When examining the values of the principal component axes, it was observed that the first principal component axis accounts for 16.81% of the total variation, the second principal component axis accounts for 14.33%, and the third principal component axis accounts for approximately 10.90%. The correlation results obtained indicate clear models and strong correlations showing significant relationships between the morphological and genetic features among the early maturing genotypes and the different groups. These findings provide strategic decisions and valuable information for plant breeding and genetic diversity studies, and they are also useful data for agricultural production and breeding efforts in line with the analyses.