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Application Research of PETD Combined with MRI Nerve Root Water Imaging in the Minimally Invasive Treatment of LDH
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作者 Guanhua Wang Zhe Shen +4 位作者 Jinben Yu Shengjie Xu Weinan Xu Bing Xu Xiaoyu Ye 《International Journal of Clinical Medicine》 CAS 2024年第4期167-176,共10页
Objective: This study aims to evaluate the safety and efficacy of PETD combined with nerve root water imaging of MRI for the treatment of lumbar disc herniation. Methods: A retrospective review was performed on 62 pat... Objective: This study aims to evaluate the safety and efficacy of PETD combined with nerve root water imaging of MRI for the treatment of lumbar disc herniation. Methods: A retrospective review was performed on 62 patients with lumbar disc herniation from March 2019 to March 2021. The study included an experimental group of 30 patients and a control group of 32 patients. The experimental group underwent PETD combined with nerve root water imaging of MRI, while the control group received traditional PETD treatment. The visual analogue scoring method (VAS score), and JOA lumbar spine function score before and after surgery were compared between the two groups, and efficacy was assessed and compared using the MacNab score. Results: The mean operation time was significantly reduced in the experimental group (56.43 &#177;10.40 minutes) compared to the control group (65.69 &#177;14.12 minutes). The VAS score was compared between the two groups with preoperative (p = 0.624), one month after surgery (p = 0.325), three months after surgery (p = 0.676), one year after surgery (p = 0.341);The JOA score was compared between the two groups with preoperative (p = 0.961), one month after the surgery (p = 0.266), three months after surgery (p = 0.185), one year after surgery (p = 0.870), they were no significant statistical difference;The efficacy evaluation of the last follow-up Macnab showed that all the 30 patients in the experimental group were excellent, 31 of 32 patients in the control group were excellent, 1 case was good;There was no statistical difference in the comparison between the two groups (p > 0.05). Conclusion: The study concludes that the combined approach of PETD with nerve root water imaging of MRI is a safe, effective, and more efficient alternative to conventional PETD for treating lumbar disc herniation. 展开更多
关键词 Lumbar Disc Herniation Nerve root water Imaging Percutaneous Interforaminal Endoscopy Minimally Invasive Spine Surgery DISCECTOMY
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Modelling soil water dynamics and root water uptake for apple trees under water storage pit irrigation 被引量:1
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作者 Xianghong Guo Tao Lei +4 位作者 Xihuan Sun Juanjuan Ma Lijian Zheng Shaowen Zhang Qiqi He 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2019年第5期126-134,共9页
Water storage pit irrigation is a new method suitable for apple trees.It comes with advantages such as water saving,water retention and drought resistance.A precise study of soil water movement and root water uptake i... Water storage pit irrigation is a new method suitable for apple trees.It comes with advantages such as water saving,water retention and drought resistance.A precise study of soil water movement and root water uptake is essential to analyse and show the advantages of the method.In this study,a mathematical model(WSPI-WR model)for 3D soil water movement and root water uptake under water storage pit irrigation was established based on soil water dynamics and soil moisture and root distributions.Moreover,this model also considers the soil evaporation,pit wall evaporation and water level variation in the pit.The finite element method was used to solve the model,and the law of mass conservation was used to analyse the water level variation.The model was validated by experimental data of the sap flow of apple trees and soil moisture in the orchard.Results showed that the WSPI-WR model is highly accurate in simulating the root water uptake and soil water distributions.The WSPI-WR model can be used to simulate root water uptake and soil water movement under water storage pit irrigation.The simulation showed that orchard soil water content and root water uptake rate centers on the storage pit with an ellipsoid distribution.The maximum distribution region of soil water and root water uptake rate was near the bottom of the pit.Distribution can reduce soil evaporation in the orchard and improve the soil water use efficiency in the middle-deep soil. 展开更多
关键词 root water uptake soil water dynamics numerical simulation water storage pit irrigation apple tree
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Effects of Optimized Root Water Uptake Parameterization Schemes on Water and Heat Flux Simulation in a Maize Agroecosystem 被引量:1
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作者 Fu CAI Huiqing MING +3 位作者 Na MI Yanbing XIE Yushu ZHANG Rongping LI 《Journal of Meteorological Research》 SCIE CSCD 2017年第2期363-377,共15页
As root water uptake(RWU)is an important link in the water and heat exchange between plants and ambient air,improving its parameterization is key to enhancing the performance of land surface model simulations.Althou... As root water uptake(RWU)is an important link in the water and heat exchange between plants and ambient air,improving its parameterization is key to enhancing the performance of land surface model simulations.Although different types of RWU functions have been adopted in land surface models,there is no evidence as to which scheme most applicable to maize farmland ecosystems.Based on the 2007–09 data collected at the farmland ecosystem field station in Jinzhou,the RWU function in the Common Land Model(Co LM)was optimized with scheme options in light of factors determining whether roots absorb water from a certain soil layer(W_x)and whether the baseline cumulative root efficiency required for maximum plant transpiration(W_c)is reached.The sensibility of the parameters of the optimization scheme was investigated,and then the effects of the optimized RWU function on water and heat flux simulation were evaluated.The results indicate that the model simulation was not sensitive to W_x but was significantly impacted by W_c.With the original model,soil humidity was somewhat underestimated for precipitation-free days;soil temperature was simulated with obvious interannual and seasonal differences and remarkable underestimations for the maize late-growth stage;and sensible and latent heat fluxes were overestimated and underestimated,respectively,for years with relatively less precipitation,and both were simulated with high accuracy for years with relatively more precipitation.The optimized RWU process resulted in a significant improvement of Co LM’s performance in simulating soil humidity,temperature,sensible heat,and latent heat,for dry years.In conclusion,the optimized RWU scheme available for the Co LM model is applicable to the simulation of water and heat flux for maize farmland ecosystems in arid areas. 展开更多
关键词 root water uptake land surface model water flux heat flux maize agroecosystem
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Proteome analysis of alfalfa roots in response to water deficit stress 被引量:5
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作者 Rahman Md Atikur Kim Yong-Goo +4 位作者 Alam Iftekhar LIU Gong-she Lee Hyoshin Lee Jeung Joo Lee Byung-Hyun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第6期1275-1285,共11页
To evaluate the response of alfalfa to water deficit (WD) stress, WD-induced candidates were investigated through a proteomic approach. Alfalfa seedlings were exposed to WD stress for 12 and 15 days respectively, fo... To evaluate the response of alfalfa to water deficit (WD) stress, WD-induced candidates were investigated through a proteomic approach. Alfalfa seedlings were exposed to WD stress for 12 and 15 days respectively, followed by 3 days re-watering. Water deficit increased H202 content, lipid peroxidation, DPPH (1,1-diphenyl-2-picrylhydrazyl)-radical scavenging activity, and the free proline level in alfalfa roots. Root proteins were extracted and separated by two-dimentional polyacrylamide gel electrophoresis (2-DE). A total of 49 WD-responsive proteins were identified in alfalfa roots; 25 proteins were reproducibly found to be up-regulated and 24 were down-regulated. Two proteins, namely cytosolic ascorbate peroxidase (APx2) and putative F-box protein were newly detected on 2-DE maps of WD-treated plants. We identified several proteins including agamous-like 65, albumin b-32, inward rectifying potassium channel, and auxin-independent growth promoter. The identified proteins are involved in a variety of cellular functions including calcium signaling, abacisic acid (ABA) biosynthesis, reactive oxygen species (ROS) regulation, transcription/translation, antioxidant/detoxification/stress defense, energy metabolism, signal transduction, and storage. These results indicate the potential candidates were responsible for adaptive response in alfalfa roots. 展开更多
关键词 ALFALFA PROTEOME root water deficit stress
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Effects of Phosphorus Application in Different Soil Layers on Root Growth, Yield, and Water-Use Efficiency of Winter Wheat Grown Under Semi-Arid Conditions 被引量:5
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作者 KANG Li-yun YUE Shan-chao LI Shi-qing 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第9期2028-2039,共12页
Deep phosphorus application can be a usefull measure to improve crops' performance in semi-arid regions, but more knowledge of both its general effects and effects on specific crops is required to optimize treatments... Deep phosphorus application can be a usefull measure to improve crops' performance in semi-arid regions, but more knowledge of both its general effects and effects on specific crops is required to optimize treatments. Thus, the aims of this study were to evaluate the effects of phosphorus(P) application at different soil layers on root growth, grain yield, and water-use efficiency(WUE) of winter wheat grown on the semi-arid Loess Plateau of China and to explore the relationship between root distribution and grain yield. The experiment consisted of four P treatments in a randomized complete block design with three replicates and two cultivars: one drought-sensitive(Xiaoyan 22, XY22) and one drought-tolerant(Changhan 58, CH58). The four P treatments were no P(control, CK), surface P(SP), deep P(DP), and deep-band P application(DBP). CH58 produced larger and deeper root systems, and had higher grain yields and WUE, under the deep P treatments(DP and DBP) than under SP, clearly showing that deep P placement had beneficial effects on the drought-tolerant cultivar. In contrast, the grain yield and root growth of XY22 did not differ between DP or DBP and SP treatments. Further, root dry weight(RW) and root length(RL) in deep soil layer(30-100 cm) were closely positively correlated with grain yield and WUE of CH58(but not XY22), highlighting the connections between a well-developed subsoil root system and both high grain yield and WUE for the drought-tolerant cultivar. WUE correlated strongly with grain yield for both cultivars(r=0.94, P〈0.001). In conclusion, deep application of P fertilizer is a practical and feasible means of increasing grain yield and WUE of rainfed winter wheat in semi-arid regions, by promoting deep root development of drought-tolerant cultivars. 展开更多
关键词 water stress phosphorus application soil layers grain yield root growth water-use efficiency
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The Response of Winter Wheat Root to the Period and the After-Effect of Soil Water Stress 被引量:4
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作者 YANG Gui-yu LUO Yuan-pei +1 位作者 LI Bao-guo LIU Xiao-ying 《Agricultural Sciences in China》 CAS CSCD 2006年第4期284-290,共7页
To reveal the period and after-effect of soil water stress on winter wheat, the article employs the experiment results carried out in the greenhouse. The results showed that the root-restricted weights varied with str... To reveal the period and after-effect of soil water stress on winter wheat, the article employs the experiment results carried out in the greenhouse. The results showed that the root-restricted weights varied with stress degrees and stress times during and after water stressing. In the course of stress, the chief reason resticting the weight of root was the stress intensity at this time, and that of severe stress treatment was larger than that of mild stress treatment. After water stress was relieved, the results of the after-effect of soil water stress on root growth were that, the stress intensity of short-time and mild stress was larger than that of long-time and severe stress. Comparing two-stage stress intensities, root-restricted weight resulted from after-effect intensity of stress under all of the short-time treatment, and the mild and the long-time stress treatments, while that resulted from the period stress intensity under the severe and the long-time stress treatments. In general, the effects of water stress on root were attributed to the three factors, a formed basis in the previous stage, the after-effect of water condition before this stage and influence of water in this stage, which lead to the characters of root in the whole growth stage. 展开更多
关键词 the period of stress after-effect of stress soil water root winter wheat
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Root Function in Nutrient Uptake and Soil Water Effect on NO3^- -N and NH4^+ -N Migration 被引量:2
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作者 SONG Hai-xing LI Sheng-xiu 《Agricultural Sciences in China》 CAS CSCD 2006年第5期377-383,共7页
Root function in uptake of nutrients and the effect of soil water on the transfer and distribution of NO3^--N in arable soil were studied using summer maize (Zea mays L. var. Shandan 9) as a testing crop. Results sh... Root function in uptake of nutrients and the effect of soil water on the transfer and distribution of NO3^--N in arable soil were studied using summer maize (Zea mays L. var. Shandan 9) as a testing crop. Results showed that root growth and water supply had a significant effect on NO3^--N transfer and made NO3^--N distributed evenly from bulk soil to rhizosphere soil. Under a natural condition with irrigation, the difference of NO3^--N concentration at different distance points from a maize plant was smaller, while obvious difference of NO3^--N concentration was observed under conditions of limited root growth space without irrigation. Whether root growth space was restricted or not, the content of soil NO3^--N decreased gradually from 10 to 0 cm from the plant, being opposite to the root absorbing area in soils. When root-grown space was limited, changes of NO3^--N concentration at different distances from a plant were similar to that of water content in tendency. Results showed that NO3^--N could be transferred as solute to plant root systems with water uptake by plants. However, the transfer and distribution of NH4^--N were not influenced by root growth and soil water supply, being different to NO3^--N. 展开更多
关键词 soil water root development nutrient transfer NITRATE AMMONIUM
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Effects of Soil Water Content on Cotton Root Growth and Distribution Under Mulched Drip Irrigation 被引量:25
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作者 HU Xiao-tang, CHEN Hu, WANG Jing, MENG Xiao-bin and CHEN Fu-hong Agricultural College, Shihezi University, Shihezi 832003, P.R.China 《Agricultural Sciences in China》 CSCD 2009年第6期709-716,共8页
The relation between soil water content and the growth of cotton root was studied for the scheme of field water and cotton yield under mulched drip irrigation. Based on the field experiments, three treatments of soil ... The relation between soil water content and the growth of cotton root was studied for the scheme of field water and cotton yield under mulched drip irrigation. Based on the field experiments, three treatments of soil water content were conducted with 90%, 75%θf, and 60%θf (θfis field water capacity). Cotton roots and root-shoot ratio were studied with digging method, and the soil moisture was observed with TDR (time domain reflector), and cotton yield was measured. The results indicated that the growth of cotton root accorded with Logistic growth curve in the three treatments, the cotton root grew quickly and its weight was very high under 75%θf because of the suitable soil water condition, while grew slowly and its weight was lower under 90%θf due to water moisture beyond the suitable condition, and the root weight was in between under 60%θf For the three water treatments, the cotton root weight decreased with soil depth, and decreased more significantly in deeper soil layer with the soil moisture increasing. And the ratio of cotton root weight in 0-30 cm soil layer to the total root weight was the highest under 75%θf. The cotton root system was distributed mainly in the soil of narrow row and wide row mulched with plastic film, and little in the soil outside plastic film. The weight of cotton root was the highest in the soil of narrow row or wide row mulched with plastic film under 75%θf. Root-shoot ratio decreased with the soil moisture increasing. The soil water content affected cotton yields, and cotton yield was the highest under 75%θf. The higher soil moisture level is unfavorable to the growth of cotton root system and yield of cotton under mulched drip irrigation. 展开更多
关键词 mulched drip irrigation cotton (Gossypium hirsutum L.) soil water content root
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Root length density distribution and associated soil water dynamics for tomato plants under furrow irrigation in a solar greenhouse 被引量:3
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作者 QIU Rangjian DU Taisheng KANG Shaozhong 《Journal of Arid Land》 SCIE CSCD 2017年第5期637-650,共14页
Furrow irrigation is a traditional widely-used irrigation method in the world. Understanding the dynamics of soil water distribution is essential to developing effective furrow irrigation strategies, especially in wat... Furrow irrigation is a traditional widely-used irrigation method in the world. Understanding the dynamics of soil water distribution is essential to developing effective furrow irrigation strategies, especially in water-limited regions. The objectives of this study are to analyze root length density distribution and to explore soil water dynamics by simulating soil water content using a HYDRUS-2D model with consideration of root water uptake for furrow irrigated tomato plants in a solar greenhouse in Northwest China. Soil water contents were also in-situ observed by the ECH_2O sensors from 4 June to 19 June and from 21 June to 4 July, 2012. Results showed that the root length density of tomato plants was concentrated in the 0–50 cm soil layers, and radiated 0–18 cm toward the furrow and 0–30 cm along the bed axis. Soil water content values simulated by the HYDRUS-2D model agreed well with those observed by the ECH_2O sensors, with regression coefficient of 0.988, coefficient of determination of 0.89, and index of agreement of 0.97. The HYDRUS-2D model with the calibrated parameters was then applied to explore the optimal irrigation scheduling. Infrequent irrigation with a large amount of water for each irrigation event could result in 10%–18% of the irrigation water losses. Thus we recommend high irrigation frequency with a low amount of water for each irrigation event in greenhouses for arid region. The maximum high irrigation amount and the suitable irrigation interval required to avoid plant water stress and drainage water were 34 mm and 6 days, respectively, for given daily average transpiration rate of 4.0 mm/d. To sum up, the HYDRUS-2D model with consideration of root water uptake can be used to improve irrigation scheduling for furrow irrigated tomato plants in greenhouses in arid regions. 展开更多
关键词 root length density distribution HYDRUS-2D model soil water content irrigation scheduling greenhouse
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Incorporation of a Dynamic Root Distribution into CLM4.5: Evaluation of Carbon and Water Fluxes over the Amazon 被引量:1
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作者 Yuanyuan WANG Zhenghui XIE B inghao JIA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第9期1047-1060,共14页
Roots are responsible for the uptake of water and nutrients by plants and have the plasticity to dynamically respond to different environmental conditions. However, most land surface models currently prescribe rooting... Roots are responsible for the uptake of water and nutrients by plants and have the plasticity to dynamically respond to different environmental conditions. However, most land surface models currently prescribe rooting profiles as a function only of vegetation type, with no consideration of the surroundings. In this study, a dynamic rooting scheme, which describes root growth as a compromise between water and nitrogen availability, was incorporated into CLM4.5 with carbon-nitrogen (CN) interactions (CLM4.5-CN) to investigate the effects of a dynamic root distribution on eco-hydrological modeling. Two paired numerical simulations were conducted for the Tapajos National Forest km83 (BRSa3) site and the Amazon, one using CLM4.5-CN without the dynamic rooting scheme and the other including the proposed scheme. Simulations for the BRSa3 site showed that inclusion of the dynamic rooting scheme increased the amplitudes and peak values of diurnal gross primary production (GPP) and latent heat flux (LE) for the dry season, and improved the carbon (C) and water cycle modeling by reducing the RMSE of GPP by 0.4 g C m^-2 d^-1, net ecosystem exchange by 1.96 g C m^-2 d^-1, LE by 5.0 W m^-2, and soil moisture by 0.03 m^3 m^-3, at the seasonal scale, compared with eddy flux measurements, while having little impact during the wet season. For the Amazon, regional analysis also revealed that vegetation responses (including GPP and LE) to seasonal drought and the severe drought of 2005 were better captured with the dynamic rooting scheme incorporated. 展开更多
关键词 CLM4.5 dynamic root distribution carbon cycle water cycle AMAZON
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Construction of Rural Grass-roots Water Conservancy Service System in the Context of Institutional Changes
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作者 Ning WANG 《Asian Agricultural Research》 2015年第11期49-52,共4页
At present,it is urgent to solve problems of reforming and improving grass-roots water conservancy management mode in rural areas and improving rural water conservancy public service ability. Through analyzing institu... At present,it is urgent to solve problems of reforming and improving grass-roots water conservancy management mode in rural areas and improving rural water conservancy public service ability. Through analyzing institutional changes of grass-roots water conservancy management in rural areas,this paper discussed current situations and outstanding problems in grass-roots water conservancy services in rural areas of Kunming City. On the basis of current situations and problems,it came up with policy recommendations from reform of management institutions,reform of personnel system,construction of human resources,development of rural water use cooperation organizations,and improvement of fund input mechanism,to build rural grass-roots water conservancy service system. 展开更多
关键词 INSTITUTIONAL CHANGES RURAL areas Grass-roots water conservancy service system POLICY RECOMMENDATIONS
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Relation of Root Growth of Rice Seedling with Nutrition and Water Use Efficiency Under Different Water Supply Conditions 被引量:1
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作者 ZHENG Bing-song JIANG De-an +3 位作者 Wu Ping WENG Xiao-yan LU Qing WANG Ni-yan 《Rice science》 SCIE 2006年第4期291-298,共8页
Water deficiency is one of the primary yield-limiting factors in rice. In plants, the nutrition and water use efficiency depend on root growth efficiency under different water supply conditions (WSC). Three rice gen... Water deficiency is one of the primary yield-limiting factors in rice. In plants, the nutrition and water use efficiency depend on root growth efficiency under different water supply conditions (WSC). Three rice genotypes, Azucena (an upland japonica), IR1552 (a lowland indica) and Jia 9522 (a lowland japonica), were grown under different WSC with 0 cm (submerged), 40 cm and 80 cm groundwater levels below the soil surface to investigate the root parameters, water use efficiency, nitrogen, phosphorous and potassium contents, net photosynthetic rate and transpiration rate of the rice plant. The relative parameters were defined as the ratio of the parameters under submerged conditions (0 cm groundwater level below soil surface) to these under upland conditions (40 cm and 80 cm groundwater levels below soil surface). The results indicated that different genotypes showed different relative root parameters and relative nutrition content and water use efficiency under different WSC. The length and number of adventitious root are more important than seminal root length in water and nutrition uptake, and maintaining the grain yield and increasing dry matter, but the adventitious root number could not be served as an index for screening drought-resistant genotypes. Furthermore, different drought-resistant genotypes have been also found, and Azucena was resistant to drought, IR1552 sensitive to drought and Jia 9522 neither sensitive nor resistant to drought. 展开更多
关键词 rice (Oryza sativa) water use efficiency water supply root parameters NITROGEN phosphorous POTASSIUM
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Water Deficit Stress Effects on Corn (<i>Zea mays</i>, L.) Root:Shoot Ratio 被引量:7
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作者 J. G. Benjamin D. C. Nielsen +2 位作者 M. F. Vigil M. M. Mikha F. Calderon 《Open Journal of Soil Science》 2014年第4期151-160,共10页
A study was conducted at Akron, CO, USA, on a Weld silt loam in 2004 to quantify the effects of water deficit stress on corn (Zea mays, L.) root and shoot biomass. Corn plants were grown under a range of soil bulk den... A study was conducted at Akron, CO, USA, on a Weld silt loam in 2004 to quantify the effects of water deficit stress on corn (Zea mays, L.) root and shoot biomass. Corn plants were grown under a range of soil bulk density and water conditions caused by previous tillage, crop rotation, and irrigation management. Water deficit stress (Dstress) was quantified by the number of days when the water content in the surface 0.3 m deviated from the water content range determined by the Least Limiting Water Range (LLWR). Root and shoot samples were collected at the V6, V12, and R1 growth stages. There was no significant correlation between Dstress and shoot or root biomass at the V6 growth stage. At the V12 and R1 growth stages, there were negative, linear correlations among Dstress and both root biomass and shoot biomass. The proportional decrease of shoot biomass was greater than the proportional decrease in root biomass, leading to an increase in the root:shoot ratio as water deficit stress increased at all growth stages. Determining restrictive soil conditions using the LLWR may be useful for evaluating improvement or degradation of the soil physical environment caused by soil management. 展开更多
关键词 SHOOT RATIO Least Limiting water Range water Stress CORN root Development Soil Environment
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Optimal root system strategies for desert phreatophytic seedlings in the search for groundwater 被引量:2
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作者 LI Changjun ZENG Fanjiang +4 位作者 ZHANG Bo LIU Bo GUO Zichun GAO Huanhuan TIYIP Tashpolat 《Journal of Arid Land》 SCIE CSCD 2015年第4期462-474,共13页
Desert phreatophytes are greatly dependent on groundwater, but how their root systems adapt to different groundwater depths is poorly understood. In the present study, shoot and root growths of Alhagi sparsifolia Shap... Desert phreatophytes are greatly dependent on groundwater, but how their root systems adapt to different groundwater depths is poorly understood. In the present study, shoot and root growths of Alhagi sparsifolia Shap. seedlings were studied across a gradient of groundwater depths. Leaves, stems and roots of different orders were measured after 120 days of different groundwater treatments. Results indicated that the depth of soil wetting front and the vertical distribution of soil water contents were highly controlled by groundwater depths. The shoot growth and biomass of A. sparsifolia decreased, but the root growth and rooting depth increased under deeper groundwater conditions. The higher ratios of root biomass, root/shoot and root length/leaf area under deeper groundwater conditions implied that seedlings of A. sparsifolia economized carbon cost on their shoot growths. The roots of A. sparsifolia distributed evenly around the soil wetting fronts under deeper groundwater conditions. Root diameters and root lengths of all orders were correlated with soil water availabilities both within and among treatments. Seedlings of A. sparsifolia produced finer first- and second-order roots but larger third- and fourth-order roots in dry soils. The results demonstrated that the root systems of desert phreatophytes can be optimized to acquire groundwater resources and maximize seedling growth by balancing the costs of carbon gain. 展开更多
关键词 desert phreatophytes root system strategy groundwater depth soil water biomass partition
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Root zone soil moisture redistribution in maize (<i>Zea mays</i>L.) under different water application regimes 被引量:1
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作者 John Mthandi Fedrick C. Kahimba +2 位作者 Andrew K. P. R. Tarimo Baanda A. Salim Maxon W. Lowole 《Agricultural Sciences》 2013年第10期521-528,共8页
Soil moisture availability to plant roots is very important for crop growth. When soil moisture is not available in the root zone, plants wilt and yield is reduced. Adequate knowledge of the distribution of soil moist... Soil moisture availability to plant roots is very important for crop growth. When soil moisture is not available in the root zone, plants wilt and yield is reduced. Adequate knowledge of the distribution of soil moisture within crop’s root zone and its linkage to the amount of water applied is very important as it assists in optimising the efficient use of water and reducing yield losses. The study aimed at evaluating the spatial redistribution of soil moisture within maize roots zone under different irrigation water application regimes. The study was conducted during two irrigatation seasons of 2012 at Nkango Irrigation Scheme, Malawi. The trials consisted of factorial arrangement in a Randomised Complete Block Design (RCBD). The factors were water and nitrogen and both were at four levels. The Triscan Sensor was used to measure volumetric soil moisture contents at different vertical and lateral points. The study inferred that the degree of soil moisture loss depends on the amount of water present in the soil. The rate of soil moisture loss in 100% of full water requirement regime (100% FWRR) treatment was higher than that in 40% FWRR treatment. This was particularly noticed when maize leaves were dry. In 100% FWRR treatment, the attraction between water and the surfaces of soil particles was not tight and as such “free” water was lost through evaporation and deep percolation, while in 40% FWRR, water was strongly attracted to and held on the soil particles surfaces and as such its potential of losing water was reduced. 展开更多
关键词 Soil Moisture Content Full Crop water Requirement Regime MAIZE root Zone
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Dry Weight Accumulation, Root Plasticity, and Stomatal Conductance in Rice (<i>Oryza sativa</i>L.) Varieties under Drought Stress and Re-Watering Conditions
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作者 Doan Cong Dien Takeo Yamakawa +1 位作者 Toshihiro Mochizuki Aung Zaw Htwe 《American Journal of Plant Sciences》 2017年第12期3189-3206,共18页
Drought is one of the main factors limiting rice (Oryza sativa L.) productivity and has become an increasingly severe problem in many regions worldwide. Establishing breeding programs to develop new drought-tolerant v... Drought is one of the main factors limiting rice (Oryza sativa L.) productivity and has become an increasingly severe problem in many regions worldwide. Establishing breeding programs to develop new drought-tolerant varieties requires an understanding of the effect of drought on rice plants and the mechanisms of drought tolerance in rice. We conducted a pot experiment to explore growth characteristics, root plasticity, and stomatal conductance in six rice varieties (DA8, Malagkit Pirurutong, Thierno Bande, Pate Blanc MN1, Kinandang Patong, and Moroberekan) in response to different drought stress and re-watering conditions. Drought stress significantly depressed plant growth, root size, and stomatal conductance in all experimental varieties. These negative effects depended on both the variety and the severity of the drought stress treatment. Under moderate drought stress (10 days after drought treatment), growth was less influenced in roots than in shoots. In contrast, there was an opposite trend under severe drought stress (15 days after drought treatment), with growth being more severely affected in roots than in shoots. Rice plants recovered from drought stress in terms of dry matter accumulation, root size, and stomatal conductance after re-watering;however, the recovery pattern differed among varieties. DA8 exhibited the highest dry weight accumulation and root size (root length, root surface area, root volume, fine root length, and thick root length) under well-watered, drought stress, and re-watering conditions. Kinandang Patong showed the highest recovery ability in dry matter accumulation, root length, root surface area, and stomatal conductance after re-watering. Malagkit Pirurutong expressed the poorest recovery ability in dry matter accumulation after re-watering. These three varieties might be selected for further experiments focusing on the mechanisms of drought tolerance and recovery ability in rice. 展开更多
关键词 Drought Tolerance Recovery Ability Re-watering RICE root Morphology
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Water adaptive traits of deep-rooted C_3 halophyte(Karelinia caspica(Pall.) Less.) and shallow-rooted C_4 halophyte(Atriplex tatarica L.) in an arid region,Northwest China
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作者 Yuan FAN PinFang LI +3 位作者 ZhenAn HOU TuSheng REN ChunLian XIONG Biao ZHANG 《Journal of Arid Land》 SCIE 2012年第4期469-478,共10页
This paper focused on the water relations of two halophytes differing in photosynthetic pathway, phe- notype, and life cycle: Karelinia caspica (Pall.) Less. (C3, deep-rooted perennial Asteraceae grass) and Atrip... This paper focused on the water relations of two halophytes differing in photosynthetic pathway, phe- notype, and life cycle: Karelinia caspica (Pall.) Less. (C3, deep-rooted perennial Asteraceae grass) and Atriplex tatarica L. (C4, shallow-rooted annual Chenopodiaceae grass). Gas exchange, leaf water potential, and growth characteristics were investigated in two growing seasons in an arid area of Xinjiang to explore the physiological adaptability of the two halophytes. Both K. caspica and A. tatarica showed midday depression of transpiration, in- dicating that they were strong xerophytes and weak midday depression types. The roots of A. tatarica were con- centrated mainly in the 0-60 cm soil layer, and the leaf water potential (~L) increased sharply in the 0-20 cm layer due to high soil water content, suggesting that the upper soil was the main water source. On the other hand, K. caspica had a rooting depth of about 1.5 m and a larger root/shoot ratio, which confirmed that this species uptakes water mainly from deeper soil layer. Although A. tatarica had lower transpiration water consumption, higher water use efficiency (WUE), and less water demand at the same leaf water potential, it showed larger water stress impact than K. caspica, indicating that the growth of A. tatarica was restricted more than that of K. caspica when there was no rainfall recharge. As a shallow-rooted C4 species, A. tatarica displayed lower stomatal conductance, which could to some extent reduce transpiration water loss and maintain leaf water potential steadily. In contrast, the deep-rooted C3 species K. caspica had a larger root/shoot ratio that was in favor of exploiting groundwater. We concluded that C3 species (K. caspica) tapes water and C4 species (A. tatarica) reduces water loss to survive in the arid and saline conditions. The results provided a case for the phenotype theory of Schwinning and Ehleringer on halophytic plants. 展开更多
关键词 Karelinia caspica Atriplex tatarica root/shoot ratio leaf water potential stomatal conductance TRANSPIRATION
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Contribution of Adventitious Roots to Water Use Strategy of Juniperus sabina in a Semiarid Area of China 被引量:1
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作者 Lingli Yang Naoko H. Miki +3 位作者 Naoko Matsuo Guosheng Zhang Linhe Wang Ken Yoshikawa 《Journal of Agricultural Science and Technology(A)》 2014年第3期251-259,共9页
关键词 半干旱地区 不定根 水资源 利用战略 中国 脉冲传感器 液压升降机 桧柏
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植物根系吸水模型研究进展
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作者 杨乐 龙兰 +3 位作者 艾施荣 施俊林 王龙飞 李紫怡 《科学技术与工程》 北大核心 2024年第4期1326-1337,共12页
根系是植物获取水分的主要器官,它直接影响整个植株的输水量以及生命活动。在水资源短缺的状况下,了解根系生长过程中的需水特性并提高农业中水资源的利用率,一直是节水灌溉技术中研究创新的热点。因此,在研究过程中需要对植物根系的吸... 根系是植物获取水分的主要器官,它直接影响整个植株的输水量以及生命活动。在水资源短缺的状况下,了解根系生长过程中的需水特性并提高农业中水资源的利用率,一直是节水灌溉技术中研究创新的热点。因此,在研究过程中需要对植物根系的吸水量进行精确估算,建立根系吸水模型是定量化研究植物根系吸水特性的重要方法。概述根系吸水的原理及其主要影响因素,对不同研究方法下的根系吸水模型进行分类研究,并阐述其适用范围及优缺点,同时介绍了水盐共同胁迫下的根系吸水模型。最后对目前的根系吸水模型进行分析,提出了今后的研究方向。研究成果为构建水稻根系三维动态吸水模型提供了基础。 展开更多
关键词 植物根系 吸水模型 宏观模型 微观模型 土壤植物大气连续体(SPAC)体系
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黄河南岸灌区玉米根系吸水来源研究
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作者 郑和祥 孙晨云 +1 位作者 刘娜 邬佳宾 《灌溉排水学报》 CAS CSCD 2024年第S01期125-130,共6页
【目的】明晰玉米根系吸水来源。【方法】采用液态水稳定氢氧同位素技术,通过监测黄河南岸灌区上、中、下游灌域的分层土壤水和玉米根系土壤水中的氢氧稳定同位素组成,结合直观图法和MIXSIAR模型确定玉米根系吸水来源,分析各供给水源的... 【目的】明晰玉米根系吸水来源。【方法】采用液态水稳定氢氧同位素技术,通过监测黄河南岸灌区上、中、下游灌域的分层土壤水和玉米根系土壤水中的氢氧稳定同位素组成,结合直观图法和MIXSIAR模型确定玉米根系吸水来源,分析各供给水源的贡献比例。【结果】拔节期玉米生长较快,需水量较大,灌区上、中、下游干旱程度不同,导致玉米根系主要吸水深度也不同。上游主要吸收0~20 cm土层的土壤水,其水源贡献率为38.1%,20~40cm土层贡献率为23.7%;中游主要吸收20~40 cm土层的土壤水,贡献率为43.6%,0~20 cm土层贡献率为27.4%;下游主要吸收20~40 cm土层的土壤水,贡献率为63%,0~20 cm土层贡献率为20%。【结论】干旱环境下玉米会改变根系吸水深度,整个生育期内玉米根系吸水深度由浅入深再变浅;且玉米对各潜在水源的利用比例与其根系吸水深度以及不同水源对土壤水的补给密切相关。 展开更多
关键词 干旱半干旱地区 玉米 稳定氢氧同位素 根系吸水 水分来源
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