Effects of drought on plant root exudates and associated rhizosphere priming effect: review and prospect

doi:10.17521/cjpe.2023.0238

Abstract

Abstract:

Root exudates play an important role in soil carbon balance, acting as an important medium for material and energy exchange and information transfer between plant roots and soil, and also the crucial forms for plant response to environmental changes. Frequent extreme drought events accompanied with global climate change have imposed a profound impact on both above- and below-ground plant growth processes. However, significant limitation exists in understanding the responses of root exudates and their mediated rhizosphere priming effect to drought due to the complexity of root-soil interface interactions and the limitation in devices and methods for collecting root exudates. This paper reviews the effects of drought on the quantity and quality of plant root exudates, with emphasis on the rhizosphere priming effect mediated by root exudates under drought stress. The future research focuses on root exudates was also discussed. This study will provide suggestion for soil carbon sink assessment under the future climate change.

Key words: drought stress, root exudates, rhizosphere priming effect, soil microorganisms, soil nutrient

LONG Ji-Lan, JIANG Zheng, LIU Ding-Qin, MIAO Yu-Xuan, ZHOU Ling-Yan, FENG Ying, PEI Jia-Ning, LIU Rui-Qiang, ZHOU Xu-Hui, FU Yu-Ling. Effects of drought on plant root exudates and associated rhizosphere priming effect: review and prospect[J]. Chin J Plant Ecol, 2024, 48(7): 817-827.

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References 85

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研究地点 Study site	研究类型 Study type	研究对象 Study object	干旱/对照(恢复) Drought/control (recovery)	干旱时间 Drought duration	根系分泌速率变化范围 Variation range of root exudation rate	参考文献 Reference
中国浙江 Zhejiang, China	野外实验 Field experiment	木荷 Schima superba	减少70%的降雨/正常降雨 70% lower rainfall/normal rainfall	10 a	-0.271↓	Jiang et al., 2023
		米槠 Castanopsis carlesii			-0.217↓
		苦槠 Castanopsis sclerophylla			-0.142↓
		柯 Lithocarpus glaber			-0.034=
德国 Germany	野外实验 Field experiment	欧洲水青冈 Fagus sylvatica	减少70%的降雨/正常降雨 70% lower rainfall/normal rainfall	5 a	0.071=	Brunn et al., 2022
德国 Germany	野外实验 Field experiment	欧洲云杉 Picea abies	减少70%的降雨/正常降雨 70% lower rainfall/normal rainfall	5 a	0.308↑	Brunn et al., 2022
波兰 Poland	盆栽实验 Pot experiment	无梗花栎 Quercus petraea	25% SWC/55% SWC	31 d	-0.665↓	Staszel et al., 2022
美国 America	盆栽实验 Pot experiment	格兰马草 Bouteloua gracilis	50% WHC, 25% WHC/100% WHC	30 d	0.506, 50%WHC= 3.007, 25%WHC↑	Ulrich et al., 2022
西班牙 Spain	盆栽实验 Pot experiment	欧洲赤松 Pinus sylvestris	10% SWC/20% SWC	14-17周 14-17 weeks	0.375=	Preece et al., 2021
西班牙 Spain	盆栽实验 Pot experiment	冬青栎 Quercus ilex	10% SWC/20% SWC	14-17周 14-17 weeks	0.091↑	Preece et al., 2021
英国 Britain	盆栽实验 Pot experiment	绒毛草 Holcus lanatus	20% WHC/60% WHC	14 d	0.783↑	de Vries et al., 2019
英国 Britain	盆栽实验 Pot experiment	酸模 Rumex acetosa	20% WHC/60% WHC	14 d	0.141=	de Vries et al., 2019
阿根廷 Argentina	培养皿 Culture dish	落花生 Arachis hypogaea (SEMIA6144)	Hoagland solution (-0.28 MPa)/ Hoagland solution (-0.07 MPa)	7 d	0.270↑	Cesari et al., 2019
阿根廷 Argentina	培养皿 Culture dish	落花生 Arachis hypogaea (Az39)		7 d	0.250↑	Cesari et al., 2019
西班牙 Spain	盆栽实验 Pot experiment	冬青栎 Quercus ilex	0.3%-22.6% SWC/20%-24.7% SWC	21 d	0.213↑	Preece et al., 2018
德国 Germany	盆栽实验 Pot experiment	大麦 Hordeum vulgare (cv. Golden Promise)	减少33%的降雨/正常降雨 33% lower rainfall/normal rainfall	91 d	-0.251=	Calvo et al., 2017
德国 Germany	盆栽实验 Pot experiment	大麦 Hordeum vulgare (cv. Bambina)	减少33%的降雨/正常降雨 33% lower rainfall/normal rainfall	91 d	-0.164=	Calvo et al., 2017
澳大利亚 Australia	盆栽实验 Pot experiment	向日葵 Helianthus annuus	40% WHC/65% WHC	14 d	2.207↑	Canarini et al., 2016
澳大利亚 Australia	盆栽实验 Pot experiment	大豆 Glycine max	40% WHC/65% WHC	14 d	0.495=	Canarini et al., 2016
加拿大 Canada	盆栽实验 Pot experiment	颤杨 Populus tremuloides	减少90%的水量/最佳水量 90% less water/optimum water	42 d	0.930=	Karst et al., 2017
美国 America	盆栽实验 Pot experiment	冰草 Agropyron cristatum	减少75%的水量/最佳水量 75% less water/optimum water	35 d	0.680↑	Henry et al., 2007

研究地点 Study site	研究类型 Study type	研究对象 Study object	干旱/对照(恢复) Drought/control (recovery)	干旱时间 Drought duration	根系分泌速率变化范围 Variation range of root exudation rate	参考文献 Reference
中国浙江 Zhejiang, China	野外实验 Field experiment	木荷 Schima superba	减少70%的降雨/正常降雨 70% lower rainfall/normal rainfall	10 a	-0.271↓	Jiang et al., 2023
		米槠 Castanopsis carlesii			-0.217↓
		苦槠 Castanopsis sclerophylla			-0.142↓
		柯 Lithocarpus glaber			-0.034=
德国 Germany	野外实验 Field experiment	欧洲水青冈 Fagus sylvatica	减少70%的降雨/正常降雨 70% lower rainfall/normal rainfall	5 a	0.071=	Brunn et al., 2022
德国 Germany	野外实验 Field experiment	欧洲云杉 Picea abies	减少70%的降雨/正常降雨 70% lower rainfall/normal rainfall	5 a	0.308↑	Brunn et al., 2022
波兰 Poland	盆栽实验 Pot experiment	无梗花栎 Quercus petraea	25% SWC/55% SWC	31 d	-0.665↓	Staszel et al., 2022
美国 America	盆栽实验 Pot experiment	格兰马草 Bouteloua gracilis	50% WHC, 25% WHC/100% WHC	30 d	0.506, 50%WHC= 3.007, 25%WHC↑	Ulrich et al., 2022
西班牙 Spain	盆栽实验 Pot experiment	欧洲赤松 Pinus sylvestris	10% SWC/20% SWC	14-17周 14-17 weeks	0.375=	Preece et al., 2021
西班牙 Spain	盆栽实验 Pot experiment	冬青栎 Quercus ilex	10% SWC/20% SWC	14-17周 14-17 weeks	0.091↑	Preece et al., 2021
英国 Britain	盆栽实验 Pot experiment	绒毛草 Holcus lanatus	20% WHC/60% WHC	14 d	0.783↑	de Vries et al., 2019
英国 Britain	盆栽实验 Pot experiment	酸模 Rumex acetosa	20% WHC/60% WHC	14 d	0.141=	de Vries et al., 2019
阿根廷 Argentina	培养皿 Culture dish	落花生 Arachis hypogaea (SEMIA6144)	Hoagland solution (-0.28 MPa)/ Hoagland solution (-0.07 MPa)	7 d	0.270↑	Cesari et al., 2019
阿根廷 Argentina	培养皿 Culture dish	落花生 Arachis hypogaea (Az39)		7 d	0.250↑	Cesari et al., 2019
西班牙 Spain	盆栽实验 Pot experiment	冬青栎 Quercus ilex	0.3%-22.6% SWC/20%-24.7% SWC	21 d	0.213↑	Preece et al., 2018
德国 Germany	盆栽实验 Pot experiment	大麦 Hordeum vulgare (cv. Golden Promise)	减少33%的降雨/正常降雨 33% lower rainfall/normal rainfall	91 d	-0.251=	Calvo et al., 2017
德国 Germany	盆栽实验 Pot experiment	大麦 Hordeum vulgare (cv. Bambina)	减少33%的降雨/正常降雨 33% lower rainfall/normal rainfall	91 d	-0.164=	Calvo et al., 2017
澳大利亚 Australia	盆栽实验 Pot experiment	向日葵 Helianthus annuus	40% WHC/65% WHC	14 d	2.207↑	Canarini et al., 2016
澳大利亚 Australia	盆栽实验 Pot experiment	大豆 Glycine max	40% WHC/65% WHC	14 d	0.495=	Canarini et al., 2016
加拿大 Canada	盆栽实验 Pot experiment	颤杨 Populus tremuloides	减少90%的水量/最佳水量 90% less water/optimum water	42 d	0.930=	Karst et al., 2017
美国 America	盆栽实验 Pot experiment	冰草 Agropyron cristatum	减少75%的水量/最佳水量 75% less water/optimum water	35 d	0.680↑	Henry et al., 2007