Ali Salehi Sardoei; Mehdi Sharifani; Mostafa Khoshhal Sarmast; Mahmoud Ghasemnejad
Abstract
Citrus species are comprised of susceptible plants that can barely tolerate freezing temperatures. To determine the relationship between cold stress tolerance (LT50) and some important physiological traits, four commercial citrus cultivars of citrus species were studied. These were Citrus unshiu, Citrus ...
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Citrus species are comprised of susceptible plants that can barely tolerate freezing temperatures. To determine the relationship between cold stress tolerance (LT50) and some important physiological traits, four commercial citrus cultivars of citrus species were studied. These were Citrus unshiu, Citrus sinensis var. ‘Thomson navel’, Citrus paradisi var. ‘Star Ru by’ and Citrus limon var. ‘Lisbon’. Assessments of cold-stress tolerance were carried out at 4, -4 and -8 °C. Ultimately, the results showed that the Japanese mandarin and ‘Thomson navel’ had the highest stress tolerance (LT50). Citrus unshiu tolerated cold stress up to -8.4 LT50. The correlation coefficient demonstrated that significant, positive correlations were observed between several pairs of attributes, i.e. LT50 and total flavonoids, chlorophyll a and chlorophyll b, carotenoids and chlorophyll a, chlorophyll b and total chlorophyll, relative moisture content and malondialdehyde, as well as glycine betaine and catalase. According to the regression coefficient, a change of one unit in lipid peroxidation caused a decrease of 1.9238 units and 5.9615 units in LT50 at +4 and -4 °C, respectively. While commercial citrus cultivars were selected for cold-tolerance and other traits, the efficiency of cold-tolerance correlated more with carotenoid content, chlorophyll content and lipid peroxidation, considering the assessments at particular temperatures.
Seyed Abolfazl Hassani; Ali Salehi Sardoei; Hamideh Azad Ghouge Bigloo; Hadi Ghasemi; Amir Ghorbanzadeh
Abstract
Various markers can be used for accurate identifications of plant genotypes and cultivars. Since microsatellite markers of simple sequence repeats (SSRs) are abundant and reliably reproducible, 14 pairs were used for evaluating polymorphic levels among 33 apple genotypes. All 14 pairs of primers had ...
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Various markers can be used for accurate identifications of plant genotypes and cultivars. Since microsatellite markers of simple sequence repeats (SSRs) are abundant and reliably reproducible, 14 pairs were used for evaluating polymorphic levels among 33 apple genotypes. All 14 pairs of primers had high degrees of polymorphism, ranging from three alleles (in the case of primers CH01h01 and CH02d12) to 12 alleles in primer CH05d04. In total, 83 polymorphic alleles appeared in these 14 SSR loci (with an average of 5.92 alleles per gene locus), and the polymorphic information content averaged 0.71. Dendrograms for molecular data were drawn based on the UPGMA method, and genotypes were divided into six main groups. The genotypes of Shahrood 20 and Shahrood 21 (95%) had the highest similarity with each other, while Shahrood 3 and Palestinian Malayer (14%) had the lowest. Principal component analysis confirmed the results of cluster analysis to determine relationships between the genotypes.
