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Growth and Photosynthetic Responses of Taraxacum coreanum Nakai Seedlings according to the Shading Levels

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Taraxacum coreanum, a member of the Asteraceae family, is endemic to Korea and has high potential as a medicinal crop. However, as the cultivation method for T. coreanum has not been clearly established, it is necessary to discuss the proper method by which to raise seedlings. In this study, the effects of the shading levels on growth and photosynthetic responses of T. coreanum were investigated. The shading treatment in this study had five levels: 35, 45, 60, 75, and 99%, respectively, designed with polyethylene shade films. The plant height, plant width, leaf length, and leaf width were highest with the 75% shading level, while the root length, root fresh weight, and dry weight tended to increase as the shading level decreased. The fresh and dry weights of the shoots were highest at the 60–75% shading levels. PIABS, representing the performance index on an absorption basis, was highest at 7.13 at the 60% shading level, showing a trend similar to that of the fresh weight and dry weight of the shoots. The maximum quantum yield of PSII (Fv/Fm) was 0.83–0.84 at shading levels of 35–75%, but it decreased to 0.74 at the 99% shading level. ΦDo, ABS/RC, and DIo/RC showed equal significance levels from shading levels of 35–75% and belonged to the normal range. However, these indicators of stress were highest at the 99% shading level, indicating that setting an excessively high shading level could significantly inactivate the reaction center of PSII. In conclusion, for the cultivation of T. coreanum under different shading levels, it is recommended to utilize shading levels of 60–75% to enhance the shoot sizes and fresh and dry weights significantly. Additionally, for significant enhancements in root length and growth, it is recommended to use shading levels of 35–75%, specifically excluding the 99% shading level.
Content may be subject to copyright.
Received: October 12, 2022
Revised: June 11, 2023
Accepted: July 6 , 2023
OPEN ACCESS
HORTICULT URAL SCIENCE and TECHNOL OGY
42(2):214-224, 2024
URL: ht tp://www.hst-j.org
pISSN : 1226-8763
eISSN : 2465-8588
This is an Open Acces s article distributed
under the terms of the Creative Commons
Attribution Non-Commercial License which
permits unrest ricted non-commercial use,
distr ibution, and reproduc tion in any medium,
provided the original work is pr operly cited.
Copyrightⓒ2024 Korean Society for
Horticultural Science.
This paper was supported by the Sahmyook
Universi ty Research Fund in 2022.
214 Horticultural Science and Technology
RESEARCH ARTICLE https: //doi .org/10.7235/HORT.20240018
차광수준에 따른 흰민들레묘의 생육과 광합성 반응
이재환1,2 · 남상1,2*
1삼육대학교 환경원예학과, 2삼육대학교 자연과학연구소
Growth and Photosynthetic Responses of
Taraxacum coreanum Nakai Seedlings according
to the Shading Levels
Jae Hwan Lee1,2 and Sang Yong Nam1,2*
1Department of Environmental Horticulture, Sahmyook University, Seoul 01795, Korea
2Natural Science Research Institute, Sahmyook University, Seoul 01795, Korea
*Correspondi ng author: namsy@syu.ac.kr
Abstract
Taraxacum coreanum, a member of the Asteraceae family, is endemic to Korea and has high
potential as a medicinal crop. However, as the cultivation method for T. coreanum has not been
clearly established, it is necessary to discuss the proper method by which to raise seedlings. In this
study, the effects of the shading levels on growth and photosynthetic responses of T. coreanum were
investigated. The shading treatment in this study had five levels: 35, 45, 60, 75, and 99%, respectively,
designed with polyethylene shade films. The plant height, plant width, leaf length, and leaf width
were highest with the 75% shading level, while the root length, root fresh weight, and dry weight
tended to increase as the shading level decreased. The fresh and dry weights of the shoots were
highest at the 6075% shading levels. PIABS, representing the performance index on an absorption
basis, was highest at 7.13 at the 60% shading level, showing a trend similar to that of the fresh
weight and dry weight of the shoots. The maximum quantum yield of PSII (Fv/Fm) was 0.830.84 at
shading levels of 3575%, but it decreased to 0.74 at the 99% shading level. ΦDo, ABS/RC, and
DIo/RC showed equal significance levels from shading levels of 3575% and belonged to the
normal range. However, these indicators of stress were highest at the 99% shading level, indicating
that setting an excessively high shading level could significantly inactivate the reaction center of
PSII. In conclusion, for the cultivation of T. coreanum under different shading levels, it is
recommended to utilize shading levels of 60 75% to enhance the shoot sizes and fresh and dry
weights significantly. Additionally, for significant enhancements in root length and growth, it is
recommended to use shading levels of 3575%, specifically excluding the 99% shading level.
Additional key words: chlorophyll fluorescence, dandelion, growth evaluation, medicinal crop, raising
seedlings
Horticultural Science and Technology 215
차광수준에 따른 흰민들레묘의 생육과 광합성 반응
국화과
(Asteraceae)
의 하위 분류인 민들레속
(Taraxacum)
은 전 세계에 약
2300
여종이 분포해 있는 것으로 알려져 있다
(RBGK and MBG, 2022).
민들레는 한의학에서 포공영으로 불리며 말린 잎을 해열
,
해독
,
이뇨에 사용하였으며 주로 간과 담
낭질환에 사용하였다
(Kang and Kim, 2001).
흰민들레
(T. coreanum)
는 서양민들레
(T. officinale)
와 달리 흰색 꽃을 가지고
있으며
(Hwang et al., 2016),
약용작물로써 더 높은 잠재가치를 지니고 있다
(Lee and Lee, 2008; Lee and Oh, 2015; Hwang et
al., 2016).
흰민들레의 물 추출물
(water extracts)
은 위염 완화에 효과가 있으며
(Yang et al., 2017),
잎과 뿌리
,
꽃에서 유래된
물 추출물은 인슐린 분비를 촉진시고 식욕을 증진시키며 소화불량 개선에도 효과가 있는 것으로 보고되었다
(Oh et al., 2012).
흰민들레는 상대적으로 서양민들레에 비해 잎의 페놀함량이 높고 뿌리 부위는 과산화수소분해효소
(catalase),
초과산화물
불균등화효소
(superoxide dismutase)
함량이 더 높은 것으로 나타났다
(Lee and Lee, 2008).
흰민들레는 다양한 연구에서 우
수한 항산화 효과를 가지는 것으로 보고되어 왔으며
(Lee and Lee, 2008; Im and Lee, 2011; Chon, 2012; Oh, 2013; Park et
al., 2015),
미백
(Park et al., 2021),
노화 억제
(Hong et al., 2021),
인지장애 개선
(He et al., 2022)
에도 효과가 있는 것으로 나
타났다
.
또한 흰민들레의 핵심 추출물인 루테올린
(luteolin)
은 흑색종 암세포와 비소세포폐암 등의 세포 사멸을 유도한다고 보
고되었다
(Yamabe et al., 2014).
그러나 흰민들레는 이러한 약용작물로써의 잠재가치에 비해 재배생산에 관한 연구는 다소 제
한적인 실정이다
.
한편
,
재배생산에 관한 연구에 앞서 육묘기간 동안 흰민들레묘를 비생물적 스트레스로부터 보호하고 묘의
안정적인 생산을 위한 육묘방법부터 확립해야 한다
.
묘의 안정적인 재배생산에 기본이 되는 차광육묘에 관한 연구가 필요하
,
흰민들레묘의 육묘에 맞는 적정 차광수준을 구명한다면 안정적인 재배생산의 기반이 마련 될 것으로 판단된다
.
차광육묘는 차광망
(shade net),
차광막
(shade film)
과 같은 재료를 활용하여 수행되며
,
이러한 인위적 차광환경의 조성은 고
,
직사광선
,
토양 수분함량의 저하와 같은 비생물적 스트레스로부터 연약한 육묘기 식물을 보호하는데 매우 효과적이다
(Fowler and Chaffee, 2010; Semchenko et al., 2012).
그러나 과도한 저조도 환경은 묘의 탄소동화작용
(carbon dioxide
assimilation)
을 제한하며 이는 생육 전반에 걸쳐 부정적인 영향을 미친다
(Clouse, 2001).
따라서 차광육묘로 인해 얻을 수 있
는 보호효과와 필요 이상의 차광으로 인한 식물의 생육 감소에 대한 적절한 균형을 고려해야한다
.
묘의 소질을 판단하는 기준
은 연구자에 따라 다르지만 일반적으로 초장
,
엽면적
,
생체중
,
건물중
,
줄기의 지름 등을 기준으로 판단해 왔다
(Kwon et al.,
2003; Bayala et al., 2009; Qu et al., 2009).
여기에 더해 대표적인 비파괴 조사방법 중 하나인 엽록소 형광
(chlorophyll
fluorescence)
분석을 추가로 활용한다면 차광수준별 식물의 스트레스 상태를 손 쉽게 파악할 수 있을 것으로 판단된다
.
이 분
석기법은 다양한 연구에 적용되어 왔으며 식물의 스트레스 수준 조사에 유용하게 사용되어 왔다
(Choi et al., 2022; Lee et al.,
2022a; Lim et al., 2022; Park et al., 2023).
이에 본 연구에서는 흰민들레묘의 안정적인 육묘에 필요한 적정 차광수준을 조사하였으며
,
차광수준에 따른 흰민들레묘의
생육수준과 광합성 지표 변화에 대한 기초자료를 제시하였다
.
재료 및 방법
식물재료
본 연구에서는 충청남도 당진시에 위치해 있는 민들레 농가로부터
2021
4
월경에 수확한 흰민들레
(Taraxacum coreanum)
종자를 보급 받아 사용하였다
.
종자는
4
주간
3°C
에 냉장보관 하여 휴면을 타파시켰으며
1mm
깊이로 육묘 트레이
1
구당 종자
1
개씩을 파종하였다
.
이때
,
평균 발아일수는
8.9
일이었고 발아율은
84%
였다
.
216 Horticultural Science and Technology
차광수준에 따른 흰민들레묘의 생육과 광합성 반응
실험환경
실험은
2022
5
4
일부터
2022
6
8
일까지 총
5
주간 서울특별시 노구에 위치해 있는 육대학 환경원예학과
실험온실
(37°38’40”N 127°06’25”E)
에서 수행하였다
.
차광리에 대한 차광수준은 총 다 가지 수준으로
용하였으며 온실 유리을 기본으로 하며
(35%),
온실유리
PE
차광막
1
(45%),
온실유리과 흰색
PE
차광막
각각
1, 2
(
각각
60, 75%),
온실유리과 흑색
PE
차광막
1
(99%)
으로 나어 적용하였다
. 5
주간 정한 상대적 차광수준
(relative shading levels)
의 평균에 대한 명은
Table 1
에 표기하였다
.
이때
,
차광리별 광도수준은 휴대용 분광사계
(SpectraPen mini, PhotonSystems Instruments, Czech Republic)
를 활용하여 실험 중 매주 평균 광합성 광량자속
(photosynthetic photon flux density)
정한 평균과 표준편차를 계산하였다
.
이때
,
광합성 광량자속도의 정은
1
시경에 수행하였으며
,
작위로 정하였다
.
실험은 원예용 유비상토
(Hanareumsangto, Shinsung Mineral, South
Korea)
가 충진 된
128
규격 트레이에 완전의배치법
(completely randomized design)
으로 트레이
1
구당
1
개체씩 총
10
체를
3
배치하였다
.
실험장소의 평균 온도와 평균 상대도는 각각
20.2 ± 5.3°C, 55.6 ± 16.8%
였으며
(Fig. 1A),
실험기간
동안의 평균 량은
(cloud cover) 4.47
(okta)
약간 흐림
수준이었다
(Fig. 1B).
관수는 주
3
수관수 하였다
.
생육수준 측정
차광수준에 따른 흰민들레묘의 생육수준을 평가하기 위해 초장과 초
,
,
엽장
,
,
엽록소 수치
(SPAD units),
지상부
와 지하부의 생체중과 건물중
,
수분함량을 조사하였다
.
식물의 초장은 지면으로부터 수직으로 식물체의 가장 높은 부위를 기
Table 1. Light intensity and the corresponding shading levels for each condition in this study
Standard shading levels (%) Relative shading levels (%) Light intensity (µmol·m-2·s-1)
0 0 1868.4 ± 151.4z
35 35.8 1197.9 ± 200.2
45 43.8 1050.0 ± 183.7
60 62.7 695.7 ± 161.1
75 75.1 465.2 ± 88.7
99 99.1 16.8 ± 3.5
zMean ± standard deviation.
Fig. 1. Changes in air temperature, relative humidity, and cloud cover in this study. Cloud cover, 0 okta: sky clear; 1-2 okta:
few clouds; 3-4 okta: scattered; 5-7 okta: broken; 8 okta: overcast; and 9 okta: sky obscured.
Horticultural Science and Technology 217
차광수준에 따른 흰민들레묘의 생육과 광합성 반응
준으로 측정하였으며
,
초폭은 식물체를 상단에서 바라볼 때 가장 넓은 부위를 기준으로 하였다
.
근장은 가장 긴 뿌리의 길이를
기준으로 측정하였다
.
잎의 엽록소 수치는 휴대용 엽록소계
(SPAD-502Plus, Konica Minolta, Japan)
를 이용하여 측정하였
으며 완전히 전개된 잎 중 무작위의 잎을 선정하여 각 반복당
10
회씩 총
3
반복으로 측정하였다
.
생체중은 식물체를 흐르는 물
에 깨끗이 씻어내고 밀폐된 공간에서
12
시간 동안 자연건조 시킨 후 측정하였다
.
건물중은 건조기
(HK-DO135F, HANKUK
S&I, South Korea)
에서
85°C
24
시간 동안 열풍건조 시킨 후 측정하였다
.
추가로 지상부와 지하부의 생체중과 건물중을 대
조하여 수분함량을 분석하였으며 관련 수식은 식
(1)
과 같다
.

⋅
(1)
(
는 수분함량
,
는 생체중
,
는 건물중을 나타낸다
)
광합성 반응 조사
차광처리의 영향을 받은 흰민들레묘의 광합성 반응을 조사하기 위해
OJIP
엽록소 형광
(OJIP chlorophyll fluorescence)
석을 수행하였으며
,
휴대용 엽록소 형광 측정기
(FluorPen FP 110/D, Photon Systems Instruments, Czech Republic)
를 사용
하여 완전히 전개된 잎의 중앙부를 기준으로 측정하였다
.
이때
,
엽록소 형광지수를 측정하기 전에 제조사의 가이드라인에 따
라 암적응용 리프클립
(dark-adaptation leaf clips)
을 활용하여 측정 부위를 약
15
분간 암적응 시켰으며
(PSI, 2022),
실험 종료
일인
2022
6
8
일에 각 반복당
10
회씩 총
3
반복 측정하였다
.
여기서 식물의 스트레스 지표로 활용이 가능한 다섯가지 형광
매개변수를 선정하여 분석하였다
.
광계
II
의 최대 양자 수율을 나타내는
Fv/Fm (2),
흡수된 광자가 소멸될 확률을 나타내는 Φ
Do
(3),
반응중심
(reaction center)
당 흡광량을 나타내는
ABS/RC (4),
반응중심당 소산되는 에너지의 양을 나타내는
DIo/RC (5),
흡광량 기반
(absorption basis)
의 성능지수
(performance index)
를 타내는
PIABS (6)
는 아래와 같은 수식을 사용하여 계산되었
(Stirbet and Govindjee, 2011; PSI, 2022).

(2)
(3)

(4)

 



(5)






(6)
통계처리
실험 결과의 분석은
SAS 9.4(SAS Institute, USA)
를 사용하여 분산분석
(ANOVA)
을 수행하였다
.
평균간 비교는
p < 0.05
수준의 던컨의 다중검정
(Duncan’s multiple range test)
으로 통계분석 하였다
.
218 Horticultural Science and Technology
차광수준에 따른 흰민들레묘의 생육과 광합성 반응
결과 및 고찰
생육수준 분석
차광리의 영향을 받은 흰민들레
(Taraxacum coreanum)
묘의 육안평가 자료는
Fig. 2
에 나타났다
.
식물체 기의 변화에
서 흰민들레묘는
75%
차광수준 하에서
5.76cm
로 가장 높은 초장을 나타었으며
,
75%
차광수준에서
13.16cm
로 가
었다
(Fig. 3A and 3B).
연구에서 소
(Myrica rubra)
50%
차광수준에서 초장
,
잎 그리고 지하부의 건물중이
Fig. 2. Taraxacum coreanum seedlings grown under different shading levels for five weeks.
Fig. 3. Plant sizes and chlorophyl l content (SPAD uni ts) responses of T. coreanum seedlings grown under different shading levels for five
weeks. Vertical bars represent the standard error, and asterisks (** and ***) indicate significance at p < 0.01 or 0.001, respectively.
Different lowercase letters indicate significant differences at p < 0.05 based on Duncan's multiple range test (DMRT). Means were
derived from three replications (n = 3), each consisting of ten plants.
Horticultural Science and Technology 219
차광수준에 따른 흰민들레묘의 생육과 광합성 반응
가장 높게 나타났으나
75%
차광수준부터는 해당 매개변수가 감소하는 경향을 나타었다
(Zeng et al., 2017).
한편
,
Echeveria agavoides
E. marcus
는 본 실험과 유사하게 차광수준이 높아질수록 초장과 초어나는 경향이 있는 것으
로 보고되었다
(Cabahug et al., 2017).
흰민들레묘의 장은
35
75%
차광수준 에서는 계적으로 유의미한 차이가
으나
,
차광수준이 아질수록 장이 높아지는 경향을 보였다
(Fig. 3C).
이전 연구에서 기린초
틀란티
’ (Phedimus
takesimensis cv. Atlantis)
(Lee and Nam, 2022)
(Delosperma cooperi)(Lee et al., 2022b)
은 본 실험의
와 유사하게 차광수준이 아질수록 장이 증가하는 경향을 나타었다
.
이러한 과는 상대적으로 식물의 수광량이 높아질
수록 식물의 뿌리 이를 증대시다는 기 연구 과와 일치하였다
(Lee et al., 2020; Huang et al., 2022).
식물은 저조도 조건에서 엽이를 나 엽면적을 키 광합성 가용 면적을 증대시키는데
(Oh and Kim, 2010),
민들레묘는
75%
차광수준에서 가장 높은 엽장과 엽을 나타었으나 보다 높은 차광수준인
99%
차광수준에서는 동화산물
적에 어려이 있어 부정적인 생육 과를 나타 것으로 추정된다
(Fig. 3D and 3E).
본 실험의 과와 유사하게 지식물
(shade plant)
의 일종인 의비름
러요시
’(Hylotelephium telephium cv. Lajos)
(Nam et al., 2022)
Amorphophallus
muelleri(Santosa et al., 2006)
의 엽장은
75%
차광수준에서 가장 어지는 것으로 나타났다
.
그러나 한편
, Begonia albopicta
B. echinosepala var. elongatifolia
62%
차광수준에서 엽면적이 가장 었으며
B. cucullata var. cucullata
B. foliosa
var. miniata
76%
수준에서 엽면적이 가장 것으로 나타나 같은 속 에서도 종마다 차이를 보였으며
(Jeong et al.,
2009),
종에 맞는 적정 차광수준에 대한 연구가 필요함을 알 수 있었다
.
국화과
(Asteraceae)
에 속한 상추
(Lactuca sativa)
종 중 청상추는 차광망
(shade net)
을 활용한 실험에서
35%
차광수준일 때 엽장과 엽이 증대되는 것으로 나타났다
(Ju et
al., 2022).
Fig. 4. Plant weight and moisture content responses of T. coreanum seedlings grown under different shading levels for five weeks. Vertical
bars represent the standard error, and asterisks (*, **, and ***) indicate significance at p < 0.05, 0.01, or 0.001, respectively. Different
lowercase letters indicate significant differences at p < 0.05 based on DMRT. Means were derived from three replications (n = 3), each
consisting of ten plants.
220 Horticultural Science and Technology
차광수준에 따른 흰민들레묘의 생육과 광합성 반응
엽록소 수치
(SPAD units)
각각
45, 60%
차광수준에서
41.27, 40.74 SPAD units
로 높게 나타났으며
,
이는 상대적으로 높
은 광도를 지
35%
차광수준에 비해 엽록소 수치가 약
18.8, 17.3%
더 높은 과였
(Fig. 3F).
한편
,
흰민들레묘는
99%
광수준에서는 엽록소 수치가
20.92 SPAD units
,
엽록소 수치가 가장 높았던
45
60%
차광수준에 비해 약
48.6
49.3%
준 더 낮았던 것으로 나타났다
. 99%
차광수준과 같이 식물의 광보상
(light compensation point)
수준 은 그 보다 은 광도
수준에서는 광합성 기의 저하로 인해 동화산물 적에 어려이 있었 것으로 보이며
,
이로 인해 잎의 발달이 저해되고
,
회피
(shade avoidance response)
이 일어 것으로 보인다
.
과적으로 세포의 기가 장함에 따라 동일 면적
세포의 도가 아지고 이에 따라 엽록소 수치 또한 아진 것으로 추정된다
.
흰민들레묘의 지상부 생체중과 건물중은
60%
차광수준에서 각각
696, 123mg
으로 가장 무거웠으며
, 75%
차광수준 하에서
535, 115mg
으로 나타났으나 서로간에 계적으로 유의미한 차이는 는 것으로 분석되었다
(Fig. 4A and 4B).
연구에서
Aglaonema brevispatha cv. Thai Snowflakes
와 나한
(Podocarpus macrophyllus var. maki)
70%
차광수준에서 가장
거운 지상부 생체중을 나타 것으로 보고되었으며
(Jeong et al., 2017),
이는 본 연구의 과와 일부 유사하였다
.
한편
,
상추와 청상추는 각각
0, 35%
차광수준에서 가장 무거운 지상부 생체중을 나타는 것으로 보고되었다
(Ju et al., 2022).
지상부 수분함량은
60%
차광수준에서
82.3%
로 가장 높게 나타나 흰민들레묘는 지상부 생육조건이 유리할수록 지상부에
상대적으로 은 수분을 저장하는 특성이 있을 알 수 있었다
(Fig. 4C).
지상부 생체중 건물중과 반대로 지하부 생체중
건물중은 차광수준이 아질수록 무거워지는 경향을 보였으며
, 35%
차광수준에서 지하부 생체중과 건물중은 각각
390,
173mg
로 가장 높게 나타났으나
45
75%
차광수준과 계적으로 유의미한 차이는 는 것으로 나타났다
(Fig. 4D and 4E).
한편
, 99%
차광수준에서는 지하부 생체중과 건물중이 각각
1.7, 0.8mg
으로 가장 게 나타났다
.
지식물 중 하나인 노루
(Hepatica asiatica)
52%
차광수준에서 가장 높은 지하부 건물중을 나타었으며
(Jeong et al., 2015),
주로 광량이 매우
에서 서식하는
A. muelleri
는 지하부에 해당하는
(corm)
와 자구
(cormels)
의 생체중이
75%
차광수준에서 가장 무거
웠던 것으로 조사되었다
(Santosa et al., 2006).
흰민들레묘의 지하부 수분함량은
60%
차광수준에서
58.9%
로 가장 높게 나타
나 지상부 수분함량이 높아질수록 지하부의 수분함량도 함 높아지는 경향이 있는 것으로 보인다
(Fig. 4F).
생육수준 분석 과 흰민들레묘의 차광육묘에서 지상부 생육이 중인 경우 식물체의 기와 생체중
,
건물중을 종합적으로
고려할 때
60
75%
차광수준 에서 재배할 것을 고하며
,
지하부의 경우
,
장과 생체중
,
건물중 모두
99%
차광수준을 제
하고는 유의미한 차이가 나타나지
35%
에서
75%
사이의 차광수준 모두 적용 가할 것으로 판단된다
.
광합성 반응 분석
차광리의 영향을 받은 흰민들레묘의 광합성 반 분석에서 다양한 과를 나타었다
(Table 2).
엽록소 형광 매개변수 중
하나인
Fv/Fm
는 스트레스를 받지 은 고등식물의 경우
0.78
0.84
위에 속하며 대 양자 수율을 나타는 매개변수로
Table 2. Photosynthetic responses of Taraxacum coreanum seedlings to the shading levels for five weeks
Shading levels (%) Fv/FmΦ
Do ABS/RC DIo/RC PIABS
35 0.83 a z0.16 b 1.83 b 0.30 b 5.05 c
45 0.83 a 0.16 b 1.72 b 0.28 b 6.28 ab
60 0.84 a 0.15 b 1.68 b 0.26 b 7.13 a
75 0.83 a 0.16 b 1.77 b 0.29 b 5.65 bc
99 0.74 b 0.25 a 2.87 a 0.80 a 1.75 d
Significance y*** *** *** *** ***
zMeans separation within columns according to Duncan’s multiple range test at p < 0.05 (n = 3).
y***: significant at p < 0.001.
Horticultural Science and Technology 221
차광수준에 따른 흰민들레묘의 생육과 광합성 반응
활용되고 있다
(Butler and Kitajima, 1975; Paillotin, 1976; Bjorkman and Demmig, 1987; Genty et al., 1989; Govindjee,
1995; Govindjee, 2004; Yoo et al., 2012). Fv/Fm
99%
차광수준을 제모든 리구에서 정상주 이인 것으로 분석되
었으며
, 99%
차광수준에서는
0.74
로 유의미하게 게 나타나 상대적으로 광계
II(PSII)
의 반중심
(reaction center)
일부가
불활성화 되었을 알 수 있었으며
,
과적으로 이는 앞서 생육수준 분석에서 급된 것처럼 생육량의 감소 등 부정적인 영향
을 보였 과와 일치하였다
.
연구에서 차나
(Camellia sinensis)
묘는 차광 환경에
Fv/Fm
가 정상주 보다 아지는
것으로 나타났으나
95%
차광환경에서 정상수준인 것으로 나타나 적절한 차광수준 하에서는 묘의 광합성 효율에 정적인 영
향을 줄 수 있을 알 수 있었다
(Shim and Jeon, 2022).
한편
,
수된 광자가 소멸될 확을 나타는 매개변수 Φ
Do
99%
광수준에서
0.25
로 가장 높게 나타나 과도하게 높은 차광수준은 광계
II
의 반심 일부를 불활성 시키는 것으로 보인다
.
한편
,
35
75%
차광 수준에서는 Φ
Do
0.15
0.16
수준으로 나타났으며
,
계적으로 유의미한 차이는 는 것으로 분석되었다
.
엽록소 형광 매개변수 중 하나인
ABS/RC
는 반중심의 비활성화 수준을 간적으로 파악할 수 있는 도가 된다
(Spoustova
et al., 2013).
이때
,
본 연구에서
99%
차광수준 하에서 재배된 흰민들레묘의
ABS/RC
2.87
로 가장 높게 나타나 비활성 상태
의 반중심의 수가 다른 차광수준에 비해 상대적으로 더 많음을 알 수 있었다
.
중심당 에지의 소산량
(dissipated energy
flux)
를 나타는 형광 매개변수
DIo/RC
Fv/Fm
Φ
Do
등과 같은 스트레스 지표들과 마가지로
99%
차광수준에서
0.80
로 가장 높게 나타났으며
,
따라서 광계
II
의 반중심이 상대적으로 높은 비활성 상태을 알 수 있었다
. Lee et al.(2022c)
의 연
구에 따르면 가지 실 관엽식물들은 고온과 연속광 조건에서 상대적으로 고광도 수준에 여있는 경우 광스트레스로 인하
DIo/RC
가 높아지는 것으로 나타났다
.
PIABS
광량을 기반
(absorption basis)
으로 한 성지수다
(Srivastava et al., 1999).
해당 지표는 광합성 활성 정도를 종합
하여 나타며 광계
II
능력
,
전자 전달 효율 전자 고정 효율의 합이다
(Thach et al., 2007). PIABS
는 광합
성 기구의 전반적인 활도를 나타
(Strasser et al., 2000; Zivcak et al., 2008),
식물의 건전성을 나타는 지표로 사용되
고 있다
(Oukarroum et al., 2007).
본 연구에서
PIABS
60%
차광수준에서
7.13
으로 가장 높게 나타났다
. PIABS
는 앞서 명된
생육수준 분석에서 지상부 생체중과 건물중이 가장 높았던 리구 중 하나인
60%
차광수준의 과와 일치하여
PIABS
가 높아
질수록 흰민들레묘가 더 은 탄소동화작용을 수행할 수 있을 간적으로 파악할 수 있었다
.
결론적으로 차광수준에 따른 흰민들레묘의 생육수준 분석과 엽록소 형광 분석기법을 기반으로한 광합성 반을 종합적으
로 평가하였을 때
,
지상부 생육이 중이 되는 경우
60
75%
차광수준에서 재배할 것을 고하며
,
지하부의 경우
99%
차광수
준을 제하고
35
75%
의 차광수준 모두 적용 가한 것으로 판단된다
.
국화과
(Asteraceae)
에 속한 흰민들레
(Taraxacum coreanum)
는 우리나라에 자생하는 고유종이다
.
흰민들레는 약용작물로
써의 잠재은 높으나 재배방법이 명확하게 확립되지 아 대량생산을 위한 육묘 방법에 대한 의가 필요하다
.
이에 본 연구
에서는 차광리가 흰민들레묘의 생육수준과 광합성 반에 어 영향을 미치는지에 대해 조사하였다
.
차광수준은 리에
필름을 활용하여 각각
35, 45, 60, 75, 99%
의 다 단계로 나어 적용하였다
.
과에서 초장
,
,
엽장
,
과 같은 식물
체의 지상부 기는
75%
리구에서 가장 우수했던 것으로 나타났다
.
그러나 이와 반대로 뿌리의
,
뿌리의 생체중과 건물
중은 차광수준이 아질수록 반비하여 높아지는 경향을 나타었다
.
한편
,
지상부 생체중과 건물중은
60
75%
차광수준에
서 가장 높았던 것으로 나타났으며
,
지수를 나타는 엽록소 형광 매개변수인
PIABS
또한 이와 유사하게
60%
리구에서
7.13
로 가장 높게 나타났다
.
광계
II
양자 수율을 나타는 매개변수인
Fv/Fm
35
75%
차광수준 에서
0.83
0.84
수준으로 나타나 정상위에 속하는 것으로 평가되었으나
99%
차광수준에서는
0.74
로 상반된 과를 나타었다
.
스트레스
지표로 활용되는 형광 매개변수인 Φ
Do, ABS/RC, DIo/RC
35
75%
의 차광수준까지 동등한 유의수준을 나타었으며 정
222 Horticultural Science and Technology
차광수준에 따른 흰민들레묘의 생육과 광합성 반응
주에 속하는 것으로 평가되었다
.
그러나
99%
차광수준에서는 가장 높게 나타나 과도하게 높은 차광수준은 광계
II
의 반
중심의 일부를 불활성화 시키는 것으로 보인다
.
결론적으로 흰민들레묘를 차광육묘할 때 지상부의 생육에 중는 경우
60
75%
차광수준에서 재배할 것을 고하며
,
지하부의 경우
99%
차광수준을 제하고
35
75%
의 차광수준에서 육묘가
한 것으로 판단된다
.
추가 주요어 :
엽록소 형광
,
민들레
,
생육평가
,
약용작물
,
육묘
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