Abstract:[Background] Drought is a limiting factor to the low productivity and even death of Populus plantations in the three-north region of China. However, the eco-physiological responses and adaptation mechanism of Populus under drought and re-watering are still not very clear.[Methods] Potted Populus simonii cuttings were used as materials and soil water contents were controlled by weighting. Three soil water levels were set:control (75%±5% of field capacity), moderate drought (50%±5%) and severe drought (25%±5%). After three months, moderate drought and severe drought treatments were re-watered to 75%±5% of field capacity. Under drought and re-watering conditions, changes of leaf photosynthesis and chlorophyll fluorescence parameters, leaf morphology and anatomy, organ biomass and non-structural carbohydrate (NSC) accumulation and distribution were investigated.[Results] Under drought conditions, root biomass allocation and soluble sugar content significantly increased, which could help to promote root water absorption, while the leaves became smaller and the aboveground growth decreased to reduce water consumption. The increase of soluble sugar and total NSC reserves in stem may contribute to the improvement of stem embolization repair ability. Under moderate drought, chlorophyll content decreased and NPQ increased, which could help to protect the photosynthetic system. And light energy utilization was increased by thickening sponge tissue. However, under severe drought, Gs and Tr were reduced by stomatal closure to maintain water status but the expense of Pn and carbon fixation. After re-watering of severe drought treatment, the Pn significantly increased and showed positive compensatory effects, which may due to the higher chlorophyll content and palisade-spongy tissue ratio than the controls under severe drought.[Conculsions]Populus simonii showed different adaption strategies to soil drought degrees by regulating organ carbon investment, leaf anatomical structure and chlorophyll content. Populus simonii showed shows obvious compensatory effects under re-watering after severe drought. Soluble sugar content in stem and roots increased under droughts, which could be helpful to embolization repair and water uptake.
高钿惠, 尚佳州, 宋立婷, 王卫锋. 小叶杨叶片光合特性与解剖结构对干旱及复水的响应[J]. 中国水土保持科学, 2021, 19(6): 18-26.
GAO Tianhui, SHANG Jiazhou, SONG Liting, WANG Weifeng. Responses of leaf photosynthetic and anatomical characteristics in Populus simonii cuttings to drought and re-watering. SSWC, 2021, 19(6): 18-26.
CHOAT B, JANSEN S, BRODRIBB T J, et al. Global convergence in the vulnerability of forests to drought[J].Nature, 2012, 491(7426):752.
[2]
DESOTO L, CAILLERET M, STERCK F, et al. Low growth resilience to drought is related to future mortality risk in trees[J]. Nature Communications, 2020, 11(1):1.
[3]
GALVEZ D A, LANDHÄUSSER S M, Tyree M T. Root carbon reserve dynamics in aspen seedlings:Does simulated drought induce reserve limitation?[J]. Tree physiology, 2011, 31(3):250.
[4]
赵瑜琦, 高苗琴, 李涛, 等. 干旱胁迫对群众杨光合特性与器官干物质分配的影响[J]. 生态学报, 2020, 40(5):1683. ZHAO Yuqi, GAO Miaoqin, LI Tao, et al. Effects of water stress on leaf gas exchange and biomass allocation of Populus×popularis ‘35-44’ cuttings[J]. Acta Ecologica Sinica, 2002, 40(5):1683.
[5]
SCHINDLBACHER A, WUNDERLICH S, BORKEN W, et al. Soil respiration under climate change:Prolonged summer drought offsets soil warming effects[J]. Global Change Biology, 2012, 18(7):1.
[6]
牛素贞, 宋勤飞, 樊卫国, 等. 干旱胁迫对喀斯特地区野生茶树幼苗生理特性及根系生长的影响[J]. 生态学报, 2017, 37(21):7333. NIU Suzhen, SONG Qinfei, FAN Weiguo, et al. Effects of drought stress on leaf physiological characteristics and root growth of the clone seedlings of wild tea plants[J]. Acta Ecologica Sinica, 2017, 37(21):7333.
[7]
王德福. 干旱与水淹胁迫对樟树幼苗生理生态特征的影响[D]. 南昌:南昌工程学院, 2018:13. WANG Defu. The effect of drought and water-logging stress on eco-physiology of Cinnamomum camphora seedlings[D]. Nanchang:Nanchang Institute of Technology, 2018:13.
[8]
CHARTZOULAKIS K, PATAKAS A, KOFIDIS G, et al. Water stress affects leaf anatomy, gas exchange, water relations and growth of two avocado cultivars[J]. Scientia Horticulturae, 2002, 95(1):39.
[9]
CHAVES M M, FLEXAS J, PINHEIRO C. Photosynthesis under drought and salt stress:regulation mechanisms from whole plant to cell[J]. Annals of Botany, 2009, 103(4):551.
[10]
杨彪生, 单立山, 马静, 等. 红砂幼苗生长及根系形态特征对干旱-复水的响应[J]. 干旱区研究, 2021, 38(2):469. YANG Biaosheng, SHAN Lishan, MA Jing, et al. Response of growth and root morphological characteristics of Reaumuria soongorica seedlings to drought-rehydration[J]. Arid Zone Research, 2021, 38(2):469.
[11]
陈梦园, 李迎超, 王利兵, 等. 2个种源栓皮栎对干旱及复水的光合生理响应[J]. 生态学杂志, 2019, 38(10):2950. CHEN Mengyuan, LI Yingchao, WANG Libing, et al. Photosynthetic responses to drought and subsequent re-watering in seedlings from two different provenances of Quercus variabilis BI[J]. Chinese Journal of Ecology, 2019, 38(10):2950.
[12]
张玉玉. 旱后复水对侧柏幼苗生长生理补偿效应的研究[D]. 陕西杨凌:西北农林科技大学, 2020:8. ZHANG Yuyu. Compensatory effects of rewatering after drought on growth and physiology of Platycladus orientalis[D]. Yangling, Shaanxi:Northwest A&F University, 2020:8.
[13]
李合生. 植物生理生化实验原理和技术[M]. 北京:高等教育出版社, 2000:134. LI Hesheng. Principle and technology of plant physiological and biochemical experiments[M]. Beijing:Higher Educaiton Press, 2000:134.
[14]
LANDHÄUSSER S M, CHOW P S, DICKMAN L T, et al. Standardized protocols and procedures can precisely and accurately quantify non-structural carbohydrates[J]. Tree Physiology, 2018, 38(12):1764.
[15]
初江涛, 王进鑫, 邹朋, 等. 干旱和铅胁迫对生长初期的国槐和侧柏叶绿素的影响[J]. 西北林学院学报, 2012, 27(4):19. CHU Jiangtao, WANG Jinxin, ZHOU Peng, et al. Effects of drought and pb stress on the contents of chlorophyls of Sophor japonica and Platycladus orientalis in their initial growth stages[J]. Journal of Northwest Forestry University, 2012, 27(4):19.
[16]
GU Junfei, ZHOU Zhenxiang, LI Zhikang, et al. Rice (Oryza sativa L.) with reduced chlorophyll content exhibit higher photosynthetic rate and efficiency, improved canopy light distribution, and greater yields than normally pigmented plants[J]. Field Crops Research, 2017(200):58.
[17]
何宝龙. 五种园林植物光合作用系统对干旱胁迫的响应研究[D]. 杭州:浙江农林大学, 2013:25. HE Baolong. The response of photosynthesis system to drought stress of five species of landscape plants[D]. Hangzhou:Zhejiang A&F University, 2013:25.
[18]
麻雪艳, 周广胜. 夏玉米叶片气体交换参数对干旱过程的响应[J]. 生态学报, 2018, 38(7):2372. MA Xueyan, ZHOU Guangsheng. Effect of drought on leaf gas exchange in summer maize[J]. Acta Ecologica Sinica, 2018, 38(7):2372.
[19]
张向娟. 干旱胁迫下棉花叶片光合特性的适应机制研究[D]. 新疆石河子:石河子大学, 2014:39. ZAHNG Xiangjuan. Photosynthetic acclimated mechanism of leaf in cotton under drought stress[D]. Shihezi, Xinjiang:Shihezi University, 2014:39.
[20]
SHIPLEY B, LECHOWICZ M J, WRIGHT I, et al. Fundamental trade-offs generating the worldwide leaf economics spectrum[J]. Ecology, 2006, 87(3):535.
[21]
温国胜, 张明如, 张国胜, 等. 干旱条件下臭柏的生理生态对策[J]. 生态学报, 2006, 26(12):4059. WEN Guosheng, ZHANG Mingru, ZAHNG Guosheng, et al. Ecophysiological strategy of Sabina vulgaris under drought stress[J]. Acta Ecologica Sinica, 2006, 26(12):4059.
[22]
IWASA Y, ROUGHGARDEN J. Shoot/root balance of plants:Optimal growth of a system with many vegetative organs[J]. Theoretical Population Biology, 1984, 25(1):78.
[23]
HACKE U G, SPERRY J S. Limits to xylem refilling under negative pressure in Laurus nobilis and Acer negundo[J]. Plant Cell and Environment, 2003, 26(2):303.
[24]
王林, 代永欣, 郭晋平, 等. 刺槐苗木干旱胁迫过程中水力学失败和碳饥饿的交互作用[J]. 林业科学, 2016, 52(6):1. WANG Lin, DAI Yongxin, GUO Jinping, et al. Interaction of hydraulic failure and carbon starvation on Robinia pseudoacacia seedlings during drought[J]. Scientia Silvae Sinicae, 2016, 52(6):1.