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2026 Vol.35, Issue 3 Preview Page

Original Articles

Analysis of the Effects of Applying a Seedling Cooling System for the Production of Healthy Strawberry Seedlings During Hot Season

고온기 딸기 건전묘 생산을 위한 육묘 냉방시스템 적용 효과 분석

Chung Geon Lee1*
,
La Hoon Cho3†
,
Sung-Wook Yun1
,
Jin Kyung Kwon2
,
Jae-Kyung Jang2
이 충건1*
,
조 라훈3†
,
윤 성욱1
,
권 진경2
,
장 재경2
1Researcher, Smart farm Development Division, National Institute of Agricultural Science, Jeonju 54875, Korea
2Senior Researcher, Smart farm Development Division, National Institute of Agricultural Science, Jeonju 54875, Korea
3Post doctoral Researcher, Smart farm Development Division, National Institute of Agricultural Science, Jeonju 54875, Korea
1국립농업과학원 스마트팜개발과 농업연구사
2국립농업과학원 스마트팜개발과 농업연구관
3국립농업과학원 스마트팜개발과 박사후연구원
*Corresponding Author
†These authors contributed equally to this work.
31 July 2026. pp. 192-202
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Abstract

High temperature and humid conditions during the strawberry nursery period increase the risk of seedling stress, disease occurrence, and poor establishment after transplanting. This study developed and evaluated a prototype seedling cooling system for high-quality strawberry (Fragaria×ananassa Duch. ‘Seolhyang’) seedlings during the hot season. The system supplied chilled water through 40A PVC pipes installed beneath 32-cell daughter-plant trays and was operated with an air-source heat pump and a chilled-water tank. Heat-transfer estimation for the 160 m cooling pipe indicated 3,843－5,157 kcal h-1 of heat exchange under assumed wind speeds of 0.3－1.0 m s-1. On 23 August 2025, when the cooling response was most distinct, the lower-bed microclimate of the cooling treatment was reduced by up to 10.7°C compared with the greenhouse air temperature and by up to 6.1°C compared with the conventional nursery treatment. The mean reductions were 6.6 and 4.3°C, respectively. In-pot root-zone temperature was reduced by up to 7.6°C, and the peak root-zone temperature decreased from 32.0°C in the conventional treatment to 26.3°C in the cooling treatment. Seedling quality was evaluated using crown diameter, plant height, petiole length, leaf length, leaf width, and SPAD. Welch's t-test showed significant improvements in crown diameter, plant height, petiole length, leaf width, and SPAD in the cooling treatment, whereas leaf length was not significantly different. After transplanting, first flower cluster emergence began on 14 October in both treatments, but the cumulative number of emerged buds in the cooling treatment increased markedly after 24 October and was 11.6% higher at the final observation. These results suggest that localized root-zone cooling can improve the thermal environment and seedling quality in open strawberry nursery greenhouses during hot seasons.

Keywords
flower-budding response
hot season
improvement of seedling quality
seedlings cooling system
strawberry seedling

본 연구는 고온기 딸기 육묘 시 근권부 고온 스트레스를 완화하고 건전묘 생산 가능성을 높이기 위해 자묘포트 하부 냉수배관을 이용한 육묘 냉방시스템 프로토타입을 개발하고, 냉방효과, 묘소질 및 본포 정식 후 출뢰 반응을 평가하였다. 개발 시스템은 4×8구 자묘포트 하부에 VN 비압력용 경질 PVC 40A 냉수배관을 접촉시키고, 공기열원 히트펌프와 2ton급 냉수탱크를 이용하여 냉수를 순환시키는 방식으로 구성되었다. 160m 배관의 열전달률은 풍속 0.3－1.0m/s조건에서 3,843－ 5,157kcal/h로 산정되었으며, 이를 바탕으로 4RT급 히트펌프 시스템을 적용하였다. 이에 따라 실험결과로, 2025년 8월 23일 기준 냉방육묘구의 자묘포트 하부 근권부 주변온도는 온실 내부기온 대비 최대 10.7°C, 평균 6.6°C 낮았고, 일반육묘구 대비 최대 6.1°C, 평균 4.3°C 낮았다. 포트 내부 근부온도는 일반육묘구 대비 최대 7.6°C, 평균 3.9°C 낮았으며, 근부 최고온도는 일반육묘구 32.0°C에서 냉방육묘구 26.3°C로 감소하였다. 또한 묘소질 조사 결과 냉방육묘구는 일반육묘구보다 관부직경, 초장, 엽병장, 엽폭 및 SPAD가 유의하게 높았으며, 엽장은 유의한 차이를 보이지 않았다. 특히 초장과 엽병장은 큰 효과크기를 보여 냉방처리에 따른 생육 개선 효과가 뚜렷하였다. 육묘 종료 후 본 포장에 딸기를 정식하였고, 본포 정식 후 1화방 최초 출뢰일은 두 처리구 모두 2025년 10월 14일로 동일하였으나, 10월 24일 이후 냉방육묘구의 누적 출뢰수가 빠르게 증가하여 조사 종료 시점에서 일반육묘구 대비 약 11.6% 높은 출뢰수를 보였다. 이상의 결과로부터 자묘포트 하부 냉수배관을 이용한 근권부 국부 냉방은 고온기 딸기 육묘온실에서 묘 주변 미기상과 포트 내부 근부온도를 낮추고, 묘소질 향상 및 정식 후 출뢰 반응 개선에 기여할 수 있는 기술로 판단되었다. 향후 반복연차 실험과 운전조건 최적화, 수량 및 경제성 분석이 필요하다.

키워드
고온기
딸기 육묘
묘소질 개선
육묘 냉방시스템
출뢰 반응
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Information
  • Publisher :The Korean Society for Bio-Environment Control
  • Publisher(Ko) :(사)한국생물환경조절학회
  • Journal Title :Journal of Bio-Environment Control
  • Journal Title(Ko) :생물환경조절학회지
  • Volume : 35
  • No :3
  • Pages :192-202
  • Received Date : 2026-05-23
  • Revised Date : 2026-06-02
  • Accepted Date : 2026-06-03
  • DOI :https://doi.org/10.12791/KSBEC.2026.35.3.192
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