Background: Hybridization between closely related fish species can generate novel phenotypes that influence aquaculture performance. This study aimed to evaluate the morphological characteristics of hybrids between the two aquaculture-relevant flounder species Kareius bicoloratus and Platichthys stellatus using a hybrid index and a newly proposed resemblance p-value-based morphometric analysis, providing insights into hybrid resemblance patterns relative to their parental species. Methods: One-year-old individuals from the three genotype groups (K. bicoloratus, P. stellatus , and hybrid) were analyzed using a combination of traditional and trussbased morphometrics. From the full dataset, 77 morphological indices were extracted, including proportions, ratios, and angular measurements. The hybrid index was computed to quantify parental resemblance, while the delta resemblance value (ΔRV) was derived from Kruskal-Wallis test to assess statistical resemblance trends. One-way ANOVA and multiple comparison tests were used to determine statistical significance among groups. Results: Hybrid flounders exhibited a complex blend of parental and hybrid-specific traits, with morphological resemblance varying by trait category. Among the 77 morphological indices, 44 (57.1%) fell within the parental range, while 33 (42.9%) exceeded parental values, demonstrating transgressive segregation or heterosis in hybrid morphology. Morphometric resemblance patterns were trait-dependent: indices relative to total length or head length tended to resemble maternal species, whereas depth-related ratios and angular traits were more similar to father. Conclusions: The integration of H-index and ΔRV analysis provided a systematic and quantitative framework for assessing hybrid morphology, offering valuable insights into phenotypic expression of hybrids, with potential relevance to aquaculture.

This study was carried out to investigate the effects of cattle slurry application in paddy land cultivated with whole crop rice on the properties of soil and water. A field study was conducted at Baeksan-myeon, Kimje, Jeonbuk province in Korea on clay loam soil for 3 years. All plots were arranged in completely randomized design with three replicates. The contents of organic and inorganic properties in soil samples collected at the end of the experiment were remarkably higher than those at the beginning of the experiment (P＜0.05). The concentrations of NO₃-N, NH₃-N and PO₄-P in discharge and leaching water were different significantly between both treatments.

This study was carried out to investigate the effects of cattle slurry application on the productivity and nutritive values of whole crop rice in paddy land. A field study was conducted at Baeksan-myeon, Kimje, Jeonbuk province in Korea on clay loam soil for 3 years. All plots were arranged in completely randomized design with three replicates. The yield of dry matter (DM) of whole crop rice in treatment of cattle slurry significantly decreased as compared with that of treatment of standard fertilizer (P＜0.05). However, nutritive values of whole crop rice were not different significantly between both treatments.

The experimental work was conducted to investigate the effects of the application level of composted cattle manure (CCM) on forage productivity using Italian ryegrass-WCR double cropping system for 3 years (2006~2008). Main plot was consisted of application level of CCM such as 150%, 200% and control plot. The total day matter yield (DMY) of Italian ryegrass and WCR in treatment of CCM 150% and CCM 200% significantly decreased as compared with that of treatment of chemical fertilizer (CF). However, NDF, AND and CP content of Italian rye grass and WCR were hardly influenced by CCM application.

The experimental work was conducted to investigate the effects of the application level of composted cattle manure (CCM) on forage productivity using rye-whole crop rice (WCR) double cropping system for 3 years. Main plot was consisted of application level of CCM such as 150%, 200% and control plot. The total DMY of of rye-WCR in treatment of CCM 150% significantly decreased as compared with that of treatment of CF and CCM 200%. However, NDF, ADF and CP content of rye and WCR were hardly influenced by CCM application.