The aim of this study is to provide basic data on the yield and bioactive compound contents of the male asparagus cultivar ‘Avalim’ grown under two cultivation systems, i.e., an open field and a rain shelter house, in the Saemangeum reclaimed land. Spear sprouting, yield parameters, polyphenol and flavonoid contents, antioxidant enzyme activities (catalase, ascorbate peroxidase, peroxidase, and superoxide dismutase), and DPPH and ABTS radical scavenging activities of 22-month-old asparagus cultivated in each system were measured. Spear sprouting occurred approximately 10 days earlier in the rain shelter house than in the open field. The number of asparagus spears per 1000 m² was approximately 600 higher in the rain shelter house, and the total weight was 21% higher than that in the open field. Polyphenol and flavonoid contents, antioxidant enzyme activities, and DPPH and ABTS radical scavenging activities were higher in the open field than in the rain shelter house. The temperature in the rain shelter house during the cultivation period was 0.6 to 17.4 °C higher than that in the open field, while light intensity was 359.7 μmol·m⁻²·s⁻¹ higher in the open field. Consequently, cultivation in Saemangeum reclaimed land resulted in higher yields in the rain shelter house, whereas the bioactive compound levels were higher in the open field. Therefore, selecting an appropriate cultivation system based on the intended purpose, focusing on yield or functional quality, when cultivating asparagus on reclaimed land is important.

Leaf area estimation using multispectral imaging in grafted cucumber seedlings is often underestimated due to leaf overlap at later growth stages. This study investigates the use of multispectral imaging technology to estimate leaf area in grafted cucumber seedlings and proposes a method to improve estimation accuracy by introducing “days after grafting” (DAG) as a correction variable. For the experiments, the scion varieties ‘Goodmorning Backdadagi’, ‘NakwonSeongCheongJang’, and ‘Sinsedae’ were grafted onto the same rootstock ‘Heukjong’ (Cucurbita ficifolia), and images were acquired at 7, 14, and 21 days after grafting. The results show that including DAG as a correction variable significantly enhances the accuracy of image-based leaf area estimation, particularly in plug tray units, where R² increased from 0.89 to 0.96 for ‘Goodmorning Backdadagi’, by effectively reducing errors caused by leaf overlap. Across all three varieties and both seasons (spring and summer), models incorporating DAG consistently showed higher accuracy in leaf area estimation than models without DAG. These results suggest that the method’s broad applicability is validated through comparisons across different seasons and varieties. Overall, this study provides a practical and accurate method for correcting leaf area estimation, with strong potential for application, particularly in seedling production and cultivation management.