본 연구는 적외선 열 영상 장치를 이용하여 2년생 ‘유미’ 복숭아나무의 토양수분 수준에 따른 엽온 및 CWSI를 분석하여 수분스트레스 측정 가능성을 검토하였다. 엽온은 대기온도와 유사한 일변화를 보이며 낮 시간대에는 대기온도보다 높은 양상을 보였다. 엽온은 전일(24시간) 기준으로 대기온도(r2 = 0.95), 일사량(r2 = 0.74), 상대습도(r2 = -0.88)와 모두 높은 상관계수를 나타났다. 또한 토양수분장력은 낮 시간대(11~16시)에 엽온(r2 = -0.57), 엽-대기온도차(r2 = -0.71), CWSI(r2 = -0.72)와 높은 부의상관을 나타냈다. CWSI와 엽온, 엽-대기온도차의 상관계수는 24시간 기준으로 매우 높았고(r2 = 0.90, r2 = 0.92), CWSI와 토양수분장력의 상관분석에서 24시간 기준으로는 상관관계가 낮았으나(r2 = -0.27), 낮 시간대(11~16시)에는 상관관계가 매우 높았다(r2 = -0.72). CWSI (y)와 토양수분장력(x)의 상관관계 결정계수(r2)는 11~12시간대에 가장 높았으며(r2 = 0.68), 이때 회귀식은 y = -0.0087x + 0.14로 조사되었다. 일반적인 토양수분스트레스 시점인 -50 kPa에 해당되는 CWSI는 0.575로 계산된다. 따라서 적외선 열 영상 장치를 이용한 엽온 및 CWSI는 토양수분장력에 대해 높은 상관계수를 나타낸 것으로 보아 복숭아나무의 수분스트레스 진단에 유용하게 활용할 수 있을 것으로 예상된다.

The study was performed to calculate canopy temperatures and crop water stress index (CWSI) of 2-year-old ‘Yumi’ peach trees using thermal infrared imaging under different soil water conditions, and to evaluate availability for water stress determination. Canopy temperatures showed similar daily variations to air temperatures and they were higher during the daytime than air temperatures. Canopy temperatures for 24 h were correlated highly to air temperatures (r2 = 0.95), solar radiations (r2 = 0.74), and relative humidity (r2 = -0.88). In addition, soil water potential showed a highly negative correlation to canopy temperatures (r2 = -0.57), temperature differences between leaf and air (TD) (r2 = -0.71), and CWSI (r2 = -0.72) during the daytime (11 to 16 h). CWSI for 24 h was highly related to canopy temperatures (r2 = 0.90) and TD (r2 = 0.92), whereas CWSI was not correlated to soil water potential (r2 = -0.27) for 24 h but related highly to water potential (r2 = -0.72) during the daytime (11 to 16 h). Correlation coefficients between CWSI (y) and soil water potential (x) were highest from 11 to 12 h and a regression equation was deduced as y = -0.0087x + 0.14. CWSI was calculated as 0.575 at -50 kPa, which soil water stress generally occurs. Thus our result suggests that this regression equation using thermal infrared imaging is useful to evaluate soil water stress of peach trees.

Abstract
서 론
재료 및 방법
    1. 실험재료 및 재배조건
    2. 토양수분 처리
    3. 복숭아 엽 온도 조사
    4. 작물 수분스트레스 지수(CWSI)
    5. 통계 분석
결과 및 고찰
    1. 대기온도, 엽온 및 일사량의 일변화
    2. 엽온(Tcanopy)과 대기온도, 일사량, 상대습도의 상관관계
    3. 토양수분에 따른 엽온 변화
    4. 토양수분과 엽온, 엽-대기온도차(TD), CWSI의 상관관계
    5. CWSI에 대한 영향 요인 분석
    6. CWSI를 활용한 토양 수분 스트레스 진단(적정시간대, 시간대별 회귀분석)
적 요

• 윤석규(농촌진흥청 국립원예특작과학원 과수학과) | Seok Kyu Yun (Department of Horticultural Crop Research, National Institute of Horticultural and Herbal Science)
• 김성종(농촌진흥청 국립원예특작과학원 과수학과) | Sung Jong Kim (Department of Horticultural Crop Research, National Institute of Horticultural and Herbal Science)
• 남은영(농촌진흥청 국립원예특작과학원 과수학과) | Eun Young Nam (Department of Horticultural Crop Research, National Institute of Horticultural and Herbal Science)
• 권정현(농촌진흥청 국립원예특작과학원 과수학과) | Jung Hyun Kwon (Department of Horticultural Crop Research, National Institute of Horticultural and Herbal Science)
• 도윤수(농촌진흥청 국립원예특작과학원 과수학과) | Yun Soo Do (Department of Horticultural Crop Research, National Institute of Horticultural and Herbal Science)
• 송승엽(농촌진흥청 국립원예특작과학원 과수학과) | Seung-Yeob Song (Department of Horticultural Crop Research, National Institute of Horticultural and Herbal Science)
• 김민영(농촌진흥청 국립농업과학원 재해예방공학과) | Minyoung Kim (Department of Agricultural Engineering, National Institute of Agricultural Sciences)
• 최용훈(농촌진흥청 국립농업과학원 재해예방공학과) | Yonghun Choi (Department of Agricultural Engineering, National Institute of Agricultural Sciences)
• 김기석(서울대학교 바이오시스템·소재학부) | Ghiseok Kim (Department of Biosystems and Biomaterials Science and Engineering, Seoul National University)
• 신현석(경남과학기술대학교 원예학과) | Hyunsuk Shin (Department of Horticulture, Gyeongnam National University of Science and Technology) Corresponding author