F. Moradipour; J.A. Olfati; Y. Hamidoghli; A. Sabouri; B. Zahedi
Abstract
Abstract Background and Objectives Identification and collection of superior genotypes in horticultural plants is the first step in breeding programs. In our country, insufficient knowledge ...
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Abstract Background and Objectives Identification and collection of superior genotypes in horticultural plants is the first step in breeding programs. In our country, insufficient knowledge about horticultural plants germplasm is the important limiting factor for improving programs on horticultural crops specially cucumber. The aim of this study was grouping of different cucumber genotypes based on some morphological traits and their genetic distances. Materials and Methods 25 cucumber lines were evaluated by measurement of 25 morphological traits using principal component and cluster analysis. Seed of all lines were obtained from the Asian Vegetable Research and Development Center (Shanhua, Tainwan). To develop transplants cucumber seeds were sown in single plastic pots (12×11 cm) filled with peat in a greenhouse. The loamy sand soil was prepared by plowing and disking. There was a preplanting application of urea nitrogen, 50 kg·ha-1, and 100 kg·ha-1 of phosphorus. The soil was formed into raised beds with rows on 1.2 m centers. Data were collected from 12 plants in a row per plot of each accession and 25 morphological traits were determined. Results The result of PCA showed that twenty main factors accounted for %88 of total variance. Contribution of each component to arrangement was 17.97, 12.25, 11.45, 8.74, 7.52, 6.12, 5.13, 4.53, 4.29, 3.77, 3.44, and 2.86 percent of total variance. Cluster analysis based on Euclidean distance and UPGMA was used to cluster the lines. According to the cluster analysis the lines were grouped in 7 clusters and cophenetic coefficient was 0.842. Discussion In this research, there was high genetic diversity between the studied lines that can be used for heterosis breeding by parental line selection for crossing to reach suitable cultivars.
