Morphological Characteristics, and Coefficient of Variation, Heritability and Genetic Advance of Major Cultivars of Spray Chrysanthemum

Abstract

The statistical analyses of coefficient of variation, heritability, and genetic advance were carried out to identify differences in morphological characteristics, such as the stem and inflorescence length, of 10 major commercial cultivars of spray chrysanthemum (Chrysanthemum morifolium). For morphological characteristics, stem lengths ranged from 46.4 cm to 54.9 cm, the maximum diameter of stem was 5.6 to 8.5 mm, the hardness of the stem was 0.17 to 0.70 kg•m-2 , the fresh weight of stem was 7.5 to 17.5 g, the dry weight of the stem was 1.6 to 3.3 g, the ratio of dry weight/fresh weight of stem was 15.9% to 23.1%. Also, the number of leaves on the stem was 8.4 to 12.2, the stem leaf area was 17.8 to 37.8 m 2 , the fresh weight stem leaves was 5.3 to 18.6 g, the dry weight was 0.5 to 1.4 g and the ratio of dry weight /fresh weight of stem leaves was 7.6% to 11.5%. The inflorescence length ranged from 10.1 to 18.6 cm, the fresh weight of inflorescence was 7.3 to 26.7 g, the dry weight of inflorescence was 1.2 to 2.8 g, the ratio of dry weight /fresh weight of inflorescence was 10.4% to 17.1%. For flower, the diameter of the flower center was 8.2 to 13.3 mm, the petal width was 5.7 to 14.0 mm, the petal length was 12.9 to 33.1 mm, and the petal thickness was 157.8 to 354.4μm. The mean values of each character in each cultivar were very different, and DMRT and LSD values based on morphological characteristics among 10 cultivars were highly significant. For variability and genetic parameters, the lowest CV (coefficient of variation), PCV (phenotypic coefficient of variation), and GCV (genotypic coefficient of variation) were 4.79% to 5.15% in stem length, and the highest variations were 62.97% to 65.21% in leaf area. ECV (error or environmental coefficient of variation) was the lowest for leaf area (1.71%) and it was the highest for leaf dry weight (19.30%). Heritability also significantly differed among the characteristics, ranging from 68.69% to 99.67%, the lowest

Assessing Amounts of Genetic Variability in Key Horticultural Traits Underlying Core Korean Breeding Lines of Cut Chrysanthemums

“…High GCV values observed in traits like FSL and FSD indicate substantial genetic control. This finding suggests these traits are highly amenable to genetic improvement [ 19 , 20 ].…”

“…In contrast, traits such as volume of flower (VF) showed lower GCV and PCV values, particularly in standard chrysanthemum types. This pattern implies that VF is less influenced by genetic factors and more by environmental conditions [ 13 , 19 , 21 ]. Given VF’s importance in standard chrysanthemums [ 1 , 2 ], the observed limited genetic variability could be attributed to restricted genetic resources in the breeding pool.…”

“…Specifically, PH, FSL, and RFW in standard chrysanthemums and PH, DFD, and VF in the spray exhibited significantly high heritability, indicating that these traits are more consistently inherited from parent to offspring and are more responsive to selective breeding efforts. Among the traits, PH consistently showed high heritability, implying its historical importance in cut chrysanthemum breeding programs [ 19 , 22 ]. The relatively high PCV and GCV for PH in both types suggest a robust gene pool influencing this trait, suggesting that PH can be reliably targeted in future Korea (K) standard or spray breeding programs, offering stable selection opportunities [ 19 , 22 ].…”

“…Among the traits, PH consistently showed high heritability, implying its historical importance in cut chrysanthemum breeding programs [ 19 , 22 ]. The relatively high PCV and GCV for PH in both types suggest a robust gene pool influencing this trait, suggesting that PH can be reliably targeted in future Korea (K) standard or spray breeding programs, offering stable selection opportunities [ 19 , 22 ].…”

“…The PCV and GCV were estimated as previously described [ 19 , 21 ]. The GCV and PCV estimates were classified as follows [ 19 , 20 , 21 ]: a value of 0–4% is represented as low, 5–14% is moderate, 15–30% is high, and >20% is very high.…”