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OsNPF3.1,a nitrate,abscisic acid and gibberellin transporter gene,is essential for rice tillering and nitrogen utilization efficiency
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作者 Junnan Hang Bowen Wu +3 位作者 Diyang Qiu Guo Yang Zhongming Fang Mingyong Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1087-1104,共18页
Low-affinity nitrate transporter genes have been identified in subfamilies 4-8 of the rice nitrate transporter 1(NRT1)/peptide transporter family(NPF),but the OsNPF3 subfamily responsible for nitrate and phytohormone ... Low-affinity nitrate transporter genes have been identified in subfamilies 4-8 of the rice nitrate transporter 1(NRT1)/peptide transporter family(NPF),but the OsNPF3 subfamily responsible for nitrate and phytohormone transport and rice growth and development remains unknown.In this study,we described OsNPF3.1 as an essential nitrate and phytohormone transporter gene for rice tillering and nitrogen utilization efficiency(NUtE).OsNPF3.1 possesses four major haplotypes of its promoter sequence in 517 cultivars,and its expression is positively associated with tiller number.Its expression was higher in the basal part,culm,and leaf blade than in other parts of the plant,and was strongly induced by nitrate,abscisic acid(ABA)and gibberellin 3(GA_3)in the root and shoot of rice.Electrophysiological experiments demonstrated that OsNPF3.1 is a pH-dependent low-affinity nitrate transporter,with rice protoplast uptake assays showing it to be an ABA and GA_3 transporter.OsNPF3.1 overexpression significantly promoted ABA accumulation in the roots and GA accumulation in the basal part of the plant which inhibited axillary bud outgrowth and rice tillering,especially at high nitrate concentrations.The NUtE of OsNPF3.1-overexpressing plants was enhanced under low and medium nitrate concentrations,whereas the NUtE of OsNPF3.1 clustered regularly interspaced short palindromic repeats(CRISPR)plants was increased under high nitrate concentrations.The results indicate that OsNPF3.1 transports nitrate and phytohormones in different rice tissues under different nitrate concentrations.The altered OsNPF3.1 expression improves NUtE in the OsNPF3.1-overexpressing and CRISPR lines at low and high nitrate concentrations,respectively. 展开更多
关键词 rice tillering grain yield PHYTOHORMONE NITRATE transporter nitrogen utilization efficiency
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Dietary supplementation with xylooligosaccharides and exogenous enzyme improves milk production,energy utilization efficiency and reduces enteric methane emissions of Jersey cows
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作者 Lifeng Dong Lei Zhao +5 位作者 Bowei Li Yanhua Gao Tianhai Yan Peter Lund Zhuofan Liu Qiyu Diao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2514-2524,共11页
Background Sustainable strategies for enteric methane(CH_(4))mitigation of dairy cows have been extensively explored to improve production performance and alleviate environmental pressure.The present study aimed to in... Background Sustainable strategies for enteric methane(CH_(4))mitigation of dairy cows have been extensively explored to improve production performance and alleviate environmental pressure.The present study aimed to investigate the effects of dietary xylooligosaccharides(XOS)and exogenous enzyme(EXE)supplementation on milk production,nutrient digestibility,enteric CH_(4) emissions,energy utilization efficiency of lactating Jersey dairy cows.Forty-eight lactating cows were randomly assigned to one of 4 treatments:(1)control diet(CON),(2)CON with 25 g/d XOS(XOS),(3)CON with 15 g/d EXE(EXE),and(4)CON with 25 g/d XOS and 15 g/d EXE(XOS+EXE).The 60-d experimental period consisted of a 14-d adaptation period and a 46-d sampling period.The enteric CO_(2)and CH_(4) emissions and O2 consumption were measured using two GreenFeed units,which were further used to determine the energy utilization efficiency of cows.Results Compared with CON,cows fed XOS,EXE or XOS+EXE significantly(P<0.05)increased milk yield,true protein and fat concentration,and energy-corrected milk yield(ECM)/DM intake,which could be reflected by the significant improvement(P<0.05)of dietary NDF and ADF digestibility.The results showed that dietary supplementation of XOS,EXE or XOS+EXE significantly(P<0.05)reduced CH_(4) emission,CH_(4)/milk yield,and CH_(4)/ECM.Furthermore,cows fed XOS demonstrated highest(P<0.05)metabolizable energy intake,milk energy output but lowest(P<0.05)of CH_(4) energy output and CH_(4) energy output as a proportion of gross energy intake compared with the remaining treatments.Conclusions Dietary supplementary of XOS,EXE or combination of XOS and EXE contributed to the improvement of lactation performance,nutrient digestibility,and energy utilization efficiency,as well as reduction of enteric CH_(4) emissions of lactating Jersey cows.This promising mitigation method may need further research to validate its long-term effect and mode of action for dairy cows. 展开更多
关键词 Energy utilization efficiency Enteric methane emissions Exogenous enzyme Jersey cows XYLOOLIGOSACCHARIDES
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Improving energy utilization efficiency of electrical discharge milling in titanium alloys machining 被引量:2
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作者 郭成波 韦东波 狄士春 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第10期2550-2557,共8页
Electrical discharge milling(ED-milling) can be a good choice for titanium alloys machining and it was proven that its machining efficiency can be improved to compete with mechanical cutting. In order to improve energ... Electrical discharge milling(ED-milling) can be a good choice for titanium alloys machining and it was proven that its machining efficiency can be improved to compete with mechanical cutting. In order to improve energy utilization efficiency of ED-milling process, unstable arc discharge and stable arc discharge combined with normal discharge were implemented for material removal by adjusting servo control strategy. The influence of electrode rotating speed and dielectric flushing pressure on machining performance was investigated by experiments. It was found that the rotating of electrode could move the position of discharge plasma channel, and high pressure flushing could wash melted debris out the discharge gap effectively. Both electrode rotating motion and high pressure flushing are contributed to the improvement of machining efficiency. 展开更多
关键词 electrical discharge milling electrode rotating dielectric flushing energy utilization efficiency material removal rate tool electrode wearing rate
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Yield gap and resource utilization efficiency of three major food crops in the world——A review 被引量:2
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作者 RONG Liang-bing GONG Kai-yuan +5 位作者 DUAN Feng-ying LI Shao-kun ZHAO Ming HE Jianqiang ZHOU Wen-bin YU Qiang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第2期349-362,共14页
Yield gap analysis could provide management suggestions to increase crop yields,while the understandings of resource utilization efficiency could help judge the rationality of the management.Based on more than 110 pub... Yield gap analysis could provide management suggestions to increase crop yields,while the understandings of resource utilization efficiency could help judge the rationality of the management.Based on more than 110 published papers and data from Food and Agriculture Organization (FAO,www.fao.org/faostat) and the Global Yield Gap and Water Productivity Atlas (www.yieldgap.org),this study summarized the concept,quantitative method of yield gap,yield-limiting factors,and resource utilization efficiency of the three major food crops (wheat,maize and rice).Currently,global potential yields of wheat,maize and rice were 7.7,10.4 and 8.5 t ha^(–1),respectively.However,actual yields of wheat,maize and rice were just 4.1,5.5 and 4.0 t ha^(–1),respectively.Climate,nutrients,moisture,crop varieties,planting dates,and socioeconomic conditions are the most mentioned yield-limiting factors.In terms of resource utilization,nitrogen utilization,water utilization,and radiation utilization efficiencies are still not optimal,and this review has summarized the main improvement measures.The current research focuses on quantitative potential yield and yield gap,with a rough explanation of yield-limiting factors.Subsequent research should use remote sensing data to improve the accuracy of the regional scale and use machine learning to quantify the role of yield-limiting factors in yield gaps and the impact of change crop management on resource utilization efficiency,so as to propose reasonable and effective measures to close yield gaps. 展开更多
关键词 food crops YIELD yield gap resource utilization efficiency yield-limiting factor
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Comprehensive evaluation of rural courtyard utilization efficiency:A case study in Shandong Province,Eastern China 被引量:1
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作者 LIU Ya-qiu WANG Ai-ling +2 位作者 HOU Jie CHEN Xin-yu XIA Jin-shan 《Journal of Mountain Science》 SCIE CSCD 2020年第9期2280-2295,共16页
China is implementing the strategy of Rural Revitalization.Revitalizing idle and inefficient utilization courtyards is an important measure for rural revitalization.The evaluation of courtyard utilization efficiency i... China is implementing the strategy of Rural Revitalization.Revitalizing idle and inefficient utilization courtyards is an important measure for rural revitalization.The evaluation of courtyard utilization efficiency is the basis of determining the idle and inefficient utilization courtyards in order to revitalizing it.This study provided a reference for the optimal use of rural courtyard utilization and revitalization through the quantitative comprehensive evaluation of courtyard utilization efficiency and the classification of courtyard utilization types.Taking Shandong Province in Eastern China as study area,we selected eight surveyed villages by stratified sampling method.According to the scale of the villages,full survey and sample survey were used,while middleaged men who familiar with the courtyards were selected as the respondents.Through a household questionnaire survey and face-to-face interviews from2017 to 2018,578 questionnaires of rural courtyardsin eight villages were obtained.Then based on the functions of rural courtyard and land resource conditions,16 comprehensive factors were formulated,involving land conditions,construction conditions and economic benefits,to build the comprehensive evaluation index system of rural courtyard utilization efficiency.Next the index weight was determined by analytic hierarchy process,and the linear weighted regression model was used to evaluate the utilization efficiency of rural courtyard.Finally,the K-means clustering analysis was used to classify the utilization efficiency of courtyards.The results showed that among the eight villages,the average utilization efficiency of courtyards was moderate(one village was low,five were moderate,and two were high).The proportions of both idle and inefficiently utilized courtyards were high.There were three vital factors leading to the idle and low efficiency of rural courtyards.They were declining rural industries,limited arable land per capita,and more farmer workers.In this case,the utilization efficiency of courtyards should be improved by transferring rural land,developing secondary and tertiary industries,evaluating the development potential of villages,classifying and optimizing courtyard utilization,so as to make full use of idle and inefficient courtyards,increase the income of farmers and collectives and promote the revitalization of rural areas. 展开更多
关键词 Rural courtyard utilization efficiency Quantitative evaluation Obstacle factor
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To Overcome the Obstacle of Data Exchange to Increase the Utilization Efficiency of Accounting Data
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《China Standardization》 2005年第1期10-11,共2页
On Nov.4th, AQSIQ (General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China), SAC (Standardization Administration of China), National Audit Office of China (CNAO), an... On Nov.4th, AQSIQ (General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China), SAC (Standardization Administration of China), National Audit Office of China (CNAO), and National Ministry of Finance of China jointly held the conference press on the national standard of Information Technology-Data Interface of Accounting Software (GB/T 19581-2004) in Beijing. The standard was approved and issued on Sept. 20, 2004 by AQSIQ and SAC, and it would come into effect all over the whole nation from January 1st, 2005. 展开更多
关键词 To Overcome the Obstacle of Data Exchange to Increase the utilization efficiency of Accounting Data SAC
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Photosynthetic Light Utilization Efficiency, Water Relations and Leaf Growth of C3 and CAM Tropical Orchids under Natural Conditions 被引量:1
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作者 Shawn Tay Jie He Tim Wing Yam 《American Journal of Plant Sciences》 2015年第18期2949-2959,共11页
Native orchid species of Singapore in their natural conditions experience stress from high irradiance, high temperatures and periods of extended low rainfall, which impact orchid plant physiology and lead to reduced g... Native orchid species of Singapore in their natural conditions experience stress from high irradiance, high temperatures and periods of extended low rainfall, which impact orchid plant physiology and lead to reduced growth and productivity. In this study, it was found that there was a reduction in photochemical efficiency of photosystem II (PSII) in 6 native orchid species under high light (HL) and Bulbophyllum membranaceum under low light (LL). There was chronic photoinhibition in these 6 orchid species over a period of 3 months after transplanting onto the tree trunks without watering and fertilization, especially in Coelogynes mayeriana and Bulbophyllum membranaceum under both HL and LL. This chronic photoinhibition caused by sustained period of water deficit in their natural conditions was later reversed by natural re-watering conditions from higher rainfall. These results indicate that water deficit has a greater impact on photosynthetic light utilization efficiency than excess light. The present study also showed that after natural rewatering, relative water content (RWC) of leaves and pseudobulbs generally increased. During the natural re-watering, total leaf area also gradually increased and reached maximum expansion after 7 weeks under both HL and LL, with some exceptions due to leaf abscission or decline in total leaf area, possibly a strategy for water conservation. 展开更多
关键词 ORCHID CAM C3 PHOTOSYNTHETIC LIGHT utilization efficiency Water Relations and LEAF Growth
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Do Higher Resource Capture Ability and Utilization Efficiency Facilitate the Successful Invasion of Exotic Plant? A Case Study of <i>Alternanthera philoxeroides</i> 被引量:5
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作者 Xuyan Geng Shang Jiang +1 位作者 Bo Li Xiaoyun Pan 《American Journal of Plant Sciences》 2013年第9期1839-1845,共7页
We tested the hypothesis that introduced populations may have higher resource capture ability and utilization efficiency than native ones of invasive plants. We compared ecophysiological traits including maximum photo... We tested the hypothesis that introduced populations may have higher resource capture ability and utilization efficiency than native ones of invasive plants. We compared ecophysiological traits including maximum photosynthetic rate (Pmax), apparent quantum yield (Q), specific leaf area (SLA), photosynthetic energy use efficiency (PEUE), photosynthetic nitrogen use efficiency (PNUE), water use efficiency (WUE), mass-based and area-based leaf construction cost (CCmass and CCarea), and mass-based and area-based leaf nitrogen concentration (Nmass and Narea) between native (Argentina) and introduced (USA) populations of two varieties (North Apa and South Apo) of Alternanthera philoxeroides under common garden conditions in China. For Apo and Apa, Pmax, Q, Nmass and WUE were not significantly different between native and introduced populations;introduced populations had significantly lower SLA and lower CCmass but significantly higher Narea and CCarea than native ones. For Apa, the introduced populations showed significantly lower PEUE and lower PNUE while for Apo, PEUE and PNUE were not significantly different between native and introduced populations. The results indicated that introduced populations of A. philoxeroides do not show higher resource capture ability and resource utilization efficiency than their native ones in the common garden experiment, suggesting that these traits may not necessarily contribute to successful invasion of invasive plants. 展开更多
关键词 INVASIVE Plant RESOURCE Use efficiency Construction Cost Leaf Nitrogen
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Panel Data Based Dynamic Evaluation of Agricultural Resource Utilization Efficiency: A Case Study of Hebei Province 被引量:1
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作者 Yajuan TIAN Li ZHEN 《Asian Agricultural Research》 2013年第4期58-59,62,共3页
Resource utilization efficiency is one of important factors influencing modern agricultural development. This paper evaluates agricultural resource utilization efficiency of Hebei Province in the Eleventh Five-Year Pl... Resource utilization efficiency is one of important factors influencing modern agricultural development. This paper evaluates agricultural resource utilization efficiency of Hebei Province in the Eleventh Five-Year Plan period by dynamic comprehensive evaluation method. Evaluation results indicate that regional disparity in agricultural resource utilization efficiency is significant, and the disparity is increasing year by year. 展开更多
关键词 AGRICULTURAL RESOURCE utilization efficiency PANEL
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Ammonia Volatilization and Nitrogen Utilization Efficiency in Response to Urea Application in Rice Fields of the Taihu Lake Region,China 被引量:63
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作者 LIN De-Xi FAN Xiao-Hui +2 位作者 HU Feng ZHAO Hong-Tao LUO Jia-Fa 《Pedosphere》 SCIE CAS CSCD 2007年第5期639-645,共7页
响应到稻田的脲申请的氨挥发损失,氮利用效率,和米饭收益在 Wangzhuang 镇上被调查, Changshu 城市,江苏省,中国。N 化肥处理,适用在三倍,是 0 (控制) , 100, 200, 300,或 350 kg N 哈 ? 1。在脲被用于地面水以后,一个连续... 响应到稻田的脲申请的氨挥发损失,氮利用效率,和米饭收益在 Wangzhuang 镇上被调查, Changshu 城市,江苏省,中国。N 化肥处理,适用在三倍,是 0 (控制) , 100, 200, 300,或 350 kg N 哈 ? 1。在脲被用于地面水以后,一个连续气流包围方法被用来在稻田测量氨挥发。通过氨挥发的全部的 N 损失通常与 N 申请率,和申请评估的二更高的 N 增加了(300 和 350 kg N 哈 ? 1 ) 证明 N 的更高的比率通过氨挥发输了到应用 N。由在全部米饭期间,生长上演的氨挥发的全部的氨损失从 9.0% ~ 16.7% 应用 N 。增加申请率通常减少了在到在植物的 N 的种子的 N 的比率。为所有 N 处理,氮肥利用效率从 30.9% ~ 45.9%。有最高的 N 率的剩余 N 导致了米饭植物,氮肥利用的减少的率,和减少的米饭收益的住宿。从这个实验计算,最节俭的 N 化肥申请率是 227 kg 哈 ? 1 为在泰胡·莱克区域的水稻土的类型。然而,推荐适当 N 化肥申请率以便植物生长被提高,氨损失被减少能改进大米的 N 利用效率。 展开更多
关键词 中国 太湖流域 水稻田 尿素 氨挥发 氮利用
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Comparative Analysis of the Utilization Efficiency of Major Agricultural Resources in Hebei Province 被引量:1
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作者 Yajuan TIAN Li ZHEN 《Asian Agricultural Research》 2014年第2期35-38,43,共5页
The utilization efficiency of resources is one of the important factors affecting the development of modern agriculture. Using production function method and ratio analysis method,we carry out the horizontal compariso... The utilization efficiency of resources is one of the important factors affecting the development of modern agriculture. Using production function method and ratio analysis method,we carry out the horizontal comparison of the utilization efficiency of major agricultural resources such as arable land,agricultural machinery power and chemical fertilizer in Hebei Province and the national level,and the vertical comparison of the utilization efficiency of major agricultural resources between the prefecture-level cities in the province. The results show that the utilization efficiency of agricultural resources in Hebei Province is below the national average,and there are significant differences in the utilization efficiency of agricultural resources between the prefecture-level cities in the province. 展开更多
关键词 AGRICULTURAL RESOURCE efficiency Regression analys
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Urban Water Resource Utilization Efficiency in China 被引量:12
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作者 SHI Tiange ZHANG Xiaolei +1 位作者 DU Hongru SHI Hui 《Chinese Geographical Science》 SCIE CSCD 2015年第6期684-697,共14页
The efficient use of water resources directly affects environmental, social, and economic development; therefore, it has a significant impact on urban populations. A slacks-based measure for data envelopment analysis(... The efficient use of water resources directly affects environmental, social, and economic development; therefore, it has a significant impact on urban populations. A slacks-based measure for data envelopment analysis(SBM-DEA) has been widely used in energy efficiency and environmental efficiency analyses in recent years. Based on this model, data from 316 cities were examined and a category method was employed involving three different sorting techniques to empirically evaluate the efficiency of urban water resource utilization in China between 2000 and 2012. The overall efficiency(OE) of urban water resource utilization in China was initially low, but has improved over the past decade. The scale efficiency(SE) was higher than the pure technological efficiency(PTE); PTE is a major determining factor of OE, and has had an increasingly significant effect. The efficiency of water resource utilization varied according to the region, urban scale, and economic function. The OE score for the eastern China was higher than for the rest of the region, and the OE score for the western China was higher than for the central China. The OE score for urban water resource utilization has improved with urban expansion, except in the case of small cities. The SE showed an inverted ′U-shaped′ trend with increasing urban expansion. The OE of urban water utilization in comprehensive functional cities was greater than in economic specialization cities, and was greater in heavy industry specialization cities than in other specialization cities. This study contributes to the field of urban water resource management by examining variations in efficiency with urban scale. 展开更多
关键词 城市水资源管理 资源利用效率 中国城市 数据包络分析方法 水资源利用 DEA模型 经济功能 技术效率
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Advances in Research on the Approaches of Improving Water Utilization Efficiency in Rice 被引量:1
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作者 ZHANGMing-sheng HUANGYou-zhong ZHANGGuo-ping 《Agricultural Sciences in China》 CAS CSCD 2005年第1期65-74,共10页
Water shortage is increasingly an important factor limiting the sustainable development of global economy, posing a hugethreat to social security and human existence. Water usage in agriculture accounts for about 70% ... Water shortage is increasingly an important factor limiting the sustainable development of global economy, posing a hugethreat to social security and human existence. Water usage in agriculture accounts for about 70% of total water consumptionin the world, and rice cultivation is in turn the largest water user, which accounts for about 50% of total water usage inagriculture. Therefore, it is quite important to improve water utilization efficiency to reduce water consumption in rice.Water stress causes severe inhibition of plant growth and development as well as yield reduction, however the extent ofinhibition or reduction varies greatly with the growth stages, duration and severity of stress, and plant genotypes. In rice,drought resistance and water utilization efficiency might be improved by developing stress resistant cultivars and conductingproper agronomic practices. It is hence imperative to determine the suitable criteria in morphological and physiologicaltraits for drought resistance and water utilization efficiency in conventional breeding of rice. At present, leaf rolling, leafwater potential and carbon isotope discrimination are commonly used criteria for the evaluation and identification ofgermplasm with high drought resistance or water utilization efficiency. With rapid development of molecular biology,marker-assisted selection has been used in rice breeding against water stress. In this review, therefore, the agronomicaspect of water saving techniques such as selection of suitable rice cultivars, planting pattern, mulching, deficit irrigationand alternative drying and moist irrigation are discussed and effective approaches are also recommended. 展开更多
关键词 水稻 水分利用效率 水分管理 水资源节约 抗旱品种 湿润灌溉 种植模式
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A major quantitative trait locus controlling phosphorus utilization efficiency under different phytate-P conditions at vegetative stage in barley 被引量:1
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作者 GAO Shang-qing CHEN Guang-deng +4 位作者 HU De-yi ZHANG Xi-zhou LI Ting-xuan LIU Shi-hang LIU Chun-ji 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第2期285-295,共11页
Organic phosphorus(P) is an important component of the soil P pool, and it has been proven to be a potential source of P for plants. The phosphorus utilization efficiency(PUE) and PUE related traits(tiller number(TN),... Organic phosphorus(P) is an important component of the soil P pool, and it has been proven to be a potential source of P for plants. The phosphorus utilization efficiency(PUE) and PUE related traits(tiller number(TN), shoot dry weight(DW), and root dry weight) under different phytate-P conditions(low phytate-P, 0.05 mmol L^(–1) and normal phytate-P, 0.5 mmol L^(–1)) were investigated using a population consisting of 128 recombinant inbred lines(RILs) at the vegetative stage in barley. The population was derived from a cross between a P-inefficient genotype(Baudin) and a P-efficient genotype(CN4027, a Hordeum spontaneum accession). A major locus(designated Qpue.sau-3 H) conferring PUE was detected in shoots and roots from the RIL population. The quantitative trait locus(QTL) was mapped on chromosome 3 H and the allele from CN4027 confers high PUE. This locus explained up to 30.3 and 28.4% of the phenotypic variance in shoots under low and normal phytate-P conditions, respectively. It also explains 28.3 and 30.7% of the phenotypic variation in root under the low and normal phytate-P conditions, respectively. Results from this study also showed that TN was not correlated with PUE, and a QTL controlling TN was detected on chromosome 5 H. However, dry weight(DW) was significantly and positively correlated with PUE, and a QTL controlling DW was detected near the Qpue.sau-3 H locus. Based on a covariance analysis, existing data indicated that, although DW may affect PUE, different genes at this locus are likely involved in controlling these two traits. 展开更多
关键词 磷利用效率 地点 控制 植物 大麦 舞台 等位基因 数据显示
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Effects of Different Rainwater Diversion Patterns on Rainwater Collection Efficiency and Water Utilization Efficiency in Cornfield 被引量:1
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作者 Wang Jianxin Wang Panlei +3 位作者 Duan Zongyan Pan Yanhua Chen Shihua Lu Yao 《Meteorological and Environmental Research》 CAS 2015年第8期54-56,共3页
Four rainwater diversion patterns including undisturbed soil ditch(T1),slope compaction(T2),asbestos sheet covering after compaction(T3) and plastic film covering after compaction(T4) were set in cornfield in arid are... Four rainwater diversion patterns including undisturbed soil ditch(T1),slope compaction(T2),asbestos sheet covering after compaction(T3) and plastic film covering after compaction(T4) were set in cornfield in arid areas of Yunnan Province,and effects of various patterns on rainwater collection efficiency,water utilization efficiency and corn yield were studied.The results shows that rainwater collection efficiency,water utilization efficiency and corn yield of the four diversion patterns presented the same trend,namely T4 > T3 > T2 > T1.Overall,rainwater collection efficiencies of the four diversion patterns ranged from 41.7%to 58.7%;compared with T1,water utilization efficiencies of T2,T3 and T4 increased by 34.9%,53.5%and 92.5%,and maize yields of them improved by 1 767.0,1 981.5 and 2 385.0 kg/hm^2. 展开更多
关键词 下线 服务 迁移
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Differences in Phosphorus Absorption and Utilization Efficiency of Soybean in Mature Period under Phosphorus Stress
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作者 Yanli ZHANG Hongling QI +2 位作者 Fengxia LU Ming HAN Panpan WANG 《Agricultural Biotechnology》 CAS 2014年第6期24-27,30,共5页
In this study,four phosphorus-inefficient soybean genotypes( D03,D05,D17 and D18) and four phosphorus-efficient soybean genotypes( D31,D34,D37 and D38) were selected as experimental materials for soil culture experime... In this study,four phosphorus-inefficient soybean genotypes( D03,D05,D17 and D18) and four phosphorus-efficient soybean genotypes( D31,D34,D37 and D38) were selected as experimental materials for soil culture experiment under high and low phosphorus treatments,to investigate the grain yield,phosphorus content,phosphorus uptake and the relationship between phosphorus utilization efficiency and phosphorus efficiency of soybean genotypes with different phosphorus efficiency in mature period. According to the experimental results,under low phosphorus treatment,four phosphorus-efficient soybean genotypes exhibited significantly high phosphorus uptake in mature period,especially for D31 and D37; however,three phosphorus-efficient genotypes showed no advantages in adaptability of phosphorus utilization efficiency,while only D31 exhibited high phosphorus utilization and absorption capacity. Correlation analysis and path analysis showed that phosphorus deficiency of soybean was mainly determined by phosphorus absorption capacity,and phosphorus deficiency under(- P) treatment was significantly higher than( + P) treatment. Phosphorus uptake and phosphorus utilization efficiency posed great direct effects on phosphorus efficiency,and phosphorus uptake exhibited a greater contribution; in addition,these two factors both posed small indirect effects. In mature period at reproductive growth stage,phosphorus absorption efficiency( phosphorus uptake) was the main variation source of phosphorus efficiency of various soybean genotypes in mature period. Therefore,strong phosphorus uptake and accumulation capacity of phosphorus-efficient soybean genotypes in mature period is an important nutrition foundation for the information of high grain yield. 展开更多
关键词 磷利用效率 成熟期间 磷吸收 大豆 磷胁迫 实验材料 粮食产量 吸收能力
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Labor Quality, Labor Utilization Efficiency and Economic Development: Regional Discrepancies and Solutions*
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《China Economist》 2012年第2期72-88,共17页
关键词 劳动力素质 经济发展 利用效率 劳动力资源 中西部地区 平均质量 东部地区 产业升级
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Effects of Nano-Carbon Water-Retaining Fertilizer on Yield and Nitrogen and Phosphorus Utilization Efficiency of Tuber Mustard
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作者 Chen WANG Ruitong WANG Zhanbin HUANG 《Asian Agricultural Research》 2018年第9期62-65,共4页
The effects of nano-carbon water-retaining fertilizer on yield,quality of tuber mustard,and fertilizer utilization efficiency were studied with the field experiments compared to the local tuber mustard fertilizer with... The effects of nano-carbon water-retaining fertilizer on yield,quality of tuber mustard,and fertilizer utilization efficiency were studied with the field experiments compared to the local tuber mustard fertilizer with equal amount of effective composition. The results showed that the yield of tuber mustard was 50 670-56 496 kg/ha in treatments of nano-carbon water-retaining fertilizer decreasing by 10%-40%,and compared with local tuber mustard fertilizer,the average yield was increased by 94. 8%. The yield increasing rate of tuber mustard was 93. 0%in treatment of nano-carbon water-retaining fertilizer decreasing by 30%. The average fertilizer utilization efficiency of nitrogen and phosphorus was 54% and 39. 7%,respectively,the average increment of fertilizer utilization efficiency was 36% and 37%,respectively compared with local tuber mustard fertilizer. Especially in treatment of reducing nano-carbon water-retaining fertilizer by 30%,the nitrogen and phosphorus fertilizer utilization efficiency was increased by 64% and 56%,respectively. By comprehensive comparison,it was found that nano-carbon waterretaining fertilizer and the treatment of 30% reduction could significantly improve the yield of tuber mustard and fertilizer utilization efficiency,and have popularization and application value in the Three Gorges Reservoir area. 展开更多
关键词 田间试验 块茎芥菜 肥料 化肥
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^(15)N Isotope Techniques for Estimating Effects of Urea-N Fertilizer Application Rate on Yields and Nutrient Contents of Pakchoi Cabbage and Asparagus Lettuce and Nitrogen Utilization Efficiency 被引量:1
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作者 LIAO Yu-lin ZHENG Sheng-xian +2 位作者 RONG Xiang-min LIU Qiang FAN Mei-rong 《Agricultural Science & Technology》 CAS 2010年第7期151-156,共6页
A pot experiment combined with15N isotope techniques was conducted to evaluate effects of the varying rates of urea-N fertilizer application on yields,quality,and nitrogen use efficiency (NUE) of pakchoi cabbage (Bras... A pot experiment combined with15N isotope techniques was conducted to evaluate effects of the varying rates of urea-N fertilizer application on yields,quality,and nitrogen use efficiency (NUE) of pakchoi cabbage (Brassica chinensis L.) and asparagus lettuce (Lactuca saiva L.).15N-labbled urea (5.3515N atom %) was added to pots with 6.5 kg soil of 0.14,0.18,0.21,0.25,and 0.29 g N/kg soil,and applied in two splits:60 percent as basal dressing in the mixture and 40 percent as topdressing.The fresh yields of two vegetable species increased with the increasing input of urea-N,but there was a significant quadratic relationship between the dose of urea-N fertilizer application and the fresh yields.When the dosage of urea-N fertilizer reached a certain value,nitrate readily accumulated in the two kinds of plants due to the decrease in NR activity; furthermore,there was a linear negative correlation between nitrate content and NR activity.With the increasing input of urea-N,ascorbic acid and soluble sugar initially increased,declined after a while,and crude fiber rapidly decreased too.Total absorbed N (TAN),N derived from fertilizer (Ndff),and N derived from soil (Ndfs) increased,and the ratio of Ndff and TAN also increased,but the ratio of Ndfs and TAN as well as NUE of urea-N fertilizer decreased with the increasing input of urea-N.These results suggested that the increasing application of labeled N fertilizer led to the increase in unlabeled N (namely,Ndfs) presumably due to "added nitrogen interaction" (ANI),the decease in NUE of urea-N fertilizer may be due to excess fertilization beyond the levels of plant requirements and the ANI,and the decrease in the two vegetable yields with the increasing addition of urea-N possibly because the excess accumulation of nitrate reached a toxic level. 展开更多
关键词 氮素利用率 氮肥施用量 蔬菜产量 同位素技术 尿素氮 小白菜 养分含量 莴笋
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Understanding the change of land space utilization efficiency with different functions and its coupling coordination: A case study of Urban Agglomeration in the Middle Reaches of the Yangtze River, China 被引量:1
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作者 YANG Bin YANG Jun +1 位作者 TAN Li XIAO Jianying 《Journal of Geographical Sciences》 SCIE CSCD 2023年第2期289-310,共22页
Land spaces function in capacities of urban development,agricultural production,and ecological conservation,among many others.Research of land space utilization efficiency(LSUE)and coupling coordination relationships ... Land spaces function in capacities of urban development,agricultural production,and ecological conservation,among many others.Research of land space utilization efficiency(LSUE)and coupling coordination relationships among its subsystems are significant for sustainable land space development.In this study,taking the Urban Agglomeration in the Middle Reaches of the Yangtze River(UAMRYR)as the study area,we establish a measurement index system to evaluate the LSUE(2000–2018)and analyze its coupling coordination degree by utilizing an improved coupling coordination model.The main results include the following.(1)The average efficiency levels of urban space and agricultural space in the UAMRYR increased 2000–2018,while the average efficiency of ecological space declined.(2)The spatial pattern of the LSUE values varied greatly,with the distributions of high-efficiency and low-efficiency levels significantly different.(3)The coupling degree of LSUE includes three types,i.e.,high-level coupling,break-in,and antagonism.Each coupling degree type was characterized by change over time.(4)The proportion of areas with high coupling coordination and moderate coupling coordination increased from 2000 to 2018,while the proportion of areas with basic coupling coordination,moderate imbalance,and serious imbalance declined during this period.Given that the spatial differentiation of the LSUE and its coupling coordination,it is necessary to implement a differential land space development strategy in the UAMRYR.This study is helpful to promote the efficient utilization and coordinated development of land space utilization systems. 展开更多
关键词 land use utilization efficiency coupling coordination sustainable development Urban Agglomeration in the Middle Reaches of the Yangtze River
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