‘EePi No.1’, a new mid-ripening cultivar of chestnut (Castanea crenata Siebold & Zucc.) was developed in 2000 by cross-pollinating two cultivars, viz., ‘Riheiguri’ and ‘Ganne’ at Korea National Institute of Forest Science. Line selection among the seedlings of ‘Riheiguri’ and ‘Ganne’ was carried out in 2007, followed by comprehensive evaluations of fruit morphological traits and tree growth characteristics conducted during 2008-2015. The harvest time of ‘EePi No.1’ was the first week of October. It is characterized by excellent nut quality, suitable for both raw consumption and processing. The average fruit weight was 24.0 g, which is significantly higher than that of the cultivar ‘Daebo’ (20.0 g). Moreover, the soluble solids content was 14.26%, and pellicle removability was 93.5%. This cultivar produces large, firm fruits with high sugar content, making it ideal for consumption. It is also characterized by excellent nut quality, suitable for both raw consumption and processing. Moreover, the easily peelable inner skin makes it ideal for processing and roasting, thereby enhancing its commercial value. These qualities are expected to bolster the diversification of income derived from forest products in the future (Registration No. 337).

Watermelons are grafted to prevent soil-borne diseases such as Fusarium wilt (FW) and increase their resistance to abiotic stress. Root-knot nematodes (RKN) are a contributing factor to economic loss in several cucurbits, including watermelon. Growing resistance varieties is an effective way to reduce the damage caused by soil-borne diseases. Resistance evaluation was performed on 50 watermelon lines to select rootstocks resistant to FW and RKN. Fusarium oxysporum f. sp. niveum race 2 was inoculated into 10-day-old seedlings using a root dipping method, and resistance was evaluated for four weeks. The 37-day-old watermelon seedlings were inoculated with Meloidogyne incognita and evaluated 60 days later. Three lines (IT199860, PI296341-6, and PI532811) were resistant to FW race 2, while one line (PI494527) was moderately resistant. Three lines (PI296341-5, PI457916-2, and PI457916-5) were RKN resistant. The PI296341-6 line was selected for its resistance to FW and moderate resistance to RKN. These findings imply that the identified resistant lines can be used in rootstock breeding programs against FW and/or RKN.

Forest tree improvement is relatively a young science and its purpose is to provide guidance for the conservation, management and sustainable utilization of genetic resources of natural and managed forests. In South Korea, forest tree improvement programs started in 1956. The programs had two main aims: to guarantee the genetic origin of the forest reproductive materials used in afforestation and reforestation, and to develop genetically improved individuals and varieties of some commercially important trees. Since the launch of the forest tree improvement programs, biomass production has been the major improvement target, together with overall adaptability to different sites. Further improvement targets have recently been added, including wood quality traits, and more specific targets linked to adaptation to abiotic and biotic factors in response to new socioeconomic needs and global changes. Additionally, since the early 1970s, forest genetic resource conservation and forest fruit and nut tree breeding have progressed in South Korea. Molecular breeding techniques based on omics information are being developed to enhance the efficacy of selection and to accelerate forest tree breeding cycles. Genetic engineering, including gene editing, has also been applied, but is currently limited to research purposes. Forest tree improvement will be an integral part of the bioeconomy in securing the production of good quality raw materials in large quantities, and will play a significant role in sequestering carbon dioxide and decelerating climate change in the long term.