Evaluation of Chloroplast Genotypes of Korean Cucumber Cultivars (Cucumis sativus L.) Using sdCAPS Markers Related to Chilling Tolerance

Abstract

Abstract. DNA markers can determine the genotype of many species. Single nucleotide polymorphism (SNP) detection is difficult without sequencing but it becomes easier with sdCAPS method. Here an experiment was performed for developing molecular markers using two SNPs, CSatpB-SNP and CSycf1-SNP, of chloroplast in cucumber plants. Properly designed primers with nucleotide sequences for restriction enzymes proved success of PCR and efficacy of digestion by the restriction enzymes. Then these markers were used to study the genotyping of cucumber breeding lines and cultivars obtained from various sources in respect of their chilling stress response. We confirmed that a U.S. cucumber line, 'NC76' known to possess a nuclear factor for the chilling tolerance showed the chloroplast genotypes related to chilling tolerance. However all Korean cucumber cultivars tested in this study showed the chloroplast genotypes related to chilling susceptibility. In conclusion, to develop chilling tolerant cucumber, both maternal and a nuclear factors related to chilling tolerance should be transferred from 'NC76' when 'NC76' is used as a female source and other elite lines as recurrent parents.

Assessment of Chilling Injury and Molecular Marker Analysis in Cucumber Cultivars (Cucumis sativus L.)

“…Various chilling tolerant and susceptible phenotypes were detected among all Korean, Japanese, and Chinese cucumbers tested in this study. However, these possessed same susceptible-associated banding morphotypes of chilling as chilling susceptible cucumber (i.e., 'GY14') as defined by Chung et al (2007), Ali et al (2013), and the results obtained in this study (Table 1).…”

“…Chilling tolerant and susceptible cucumber germplasms used in this study were obtained from different sources including the U. S. Ali et al, 2013) and one from Japan ('Suiseifushinari 2-go' unknown chilling response; Ali et al, 2013). The Korean accessions used were selected either because of their known chilling injury (CI) tolerance according to seed companies (Ali et al, 2013) or their importance to the Korean horticulture industry.…”

“…The Korean accessions used were selected either because of their known chilling injury (CI) tolerance according to seed companies (Ali et al, 2013) or their importance to the Korean horticulture industry. The phenotypic response to chilling temperatures (4°C) and nuclear and chloroplast genotype of line NC76 and 'Chipper' were previously classified by Chung et al (2003b), Kozik and Wehner (2008) and Gordon and Staub (2011), and were used herein as standards for comparison.…”

“…To determine chloroplast marker/chilling phenotype associations in Korean fresh market cucumber, two sdCAPS chloroplast markers, CSatpB-SNP and CSycf1-SNP developed by Ali et al (2013) were employed to define the chloroplast genotype designations of 'Nacdongchungjang' (phenotypically chilling susceptible) and 'Janghyungnachap' (phenotypically chilling tolerant) (phenotypic chilling response designated by this study). Likewise, these markers were also employed for genotypic characterization of chilling susceptible cucumber cultivars, 'Joeunbaegdadagi', 'Sinjungpum', 'White', 'Dongguan', and chilling tolerant line NC76 according to Ali et al (2013).…”

“…Likewise, these markers were also employed for genotypic characterization of chilling susceptible cucumber cultivars, 'Joeunbaegdadagi', 'Sinjungpum', 'White', 'Dongguan', and chilling tolerant line NC76 according to Ali et al (2013).…”