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Morpho-Physiological Characterization of Glyphosate-Resistant and -Susceptible Horseweed (Conyza canadensis) Biotypes of US Midsouth

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American Journal of Plant Sciences 2015年第1期6卷 47-56页

作者： Vijay K. Nandula Daniel H. Poston Clifford H. Koger Krishna N. Reddy K. Raja Reddy US Department of Agriculture-Agricultural Research Service (USDA-ARS) Crop Production Systems Research Unit Stoneville MS USA Pioneer Hi-Bred International—Southern Business Unit Huntsville AL USA silent shade planting company Belzoni MS USA Department of Plant and Soil Sciences Mississippi State University Mississippi State MS USA

Horseweed is traditionally considered a non-cropland weed. However, populations resistant to glyphosate have eventually become established in no-till agronomic cropping systems. Growth chamber and greenhouse experiments were conducted to compare selected biological and physiological parameters of glyphosate-resistant (GR) and -susceptible (GS) horseweed biotypes from Mississippi with a broader goal of fitness characterization in these biotypes. Vegetative growth parameters (number of leaves, rosette diameter and area, shoot and root fresh weights) were recorded weekly from 5 to 11 wk after emergence and reproductive attributes [days to bolting (production of a flowering stalk) and flowering] and senescence were measured for both GR and GS biotypes under high (24°C/20°C) and low (18°C/12°C) temperature regimes, both with a 13-h light period. Physiological traits such as net photosynthesis, phenolic content, and cell membrane thermostability, all in the presence and absence of glyphosate, and leaf content of divalent cations such as Ca2+ and Mg2+ were assayed in the two biotypes under the high temperature regime. All horseweed vegetative growth parameters except root fresh weight were higher in the high temperature regime compared to that in low temperature regime in both biotypes. Number of leaves, rosette diameter and area, shoot and root fresh weight were 40 vs. 35, 9.3 vs. 8.7 cm, 51 vs. 43 cm2, 3.7 vs. 3.2 g, and 3.5 vs. 4.2 g under high and low temperature conditions, respectively, when averaged across biotypes and weekly measurements. All growth parameters listed above were higher for the GR biotype compared to the GS biotype. Number of leaves, rosette diameter and area, shoot and root fresh weight were 38 vs. 37, 9.1 vs. 8.9 cm, 50.2 vs. 44 cm2, 3.9 vs. 3.1 g, and 4.3 vs. 3.5 g for GR and GS biotypes, respectively, averaged across the temperature treatments and weekly measurements. Reproductive developmental data of these biotypes indicated that the GS biotype

关键词： Conyza canadensis Glyphosate Growth Fitness Horseweed Resistance

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Retention of eucalyptus harvest residues reduces soil compaction caused by deep subsoiling

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Journal of Forestry Research 2022年第2期33卷 643-651页

作者： Raphael Oliveira de Melo AymbiréAngeletti da Fonseca Nairam Félix de Barros Raphael Bragança Alves Fernandes Rafael da Silva Teixeira Iago Nery Melo Ricardo Previdente Martins Soil Science Department Universidade Federal de ViçosaViçosaMinas GeraisBrazil BRACELL company AlagoinhasBahiaBrazil

Eucalyptus harvesting,forwarding and soil tillage operations are among the main causes for compaction of forest soils,with potential impacts on *** concern is especially important in areas with soils that are naturally compacted(fragipans and duripans).In these soils,tillage operations include the use of subsoilers that can reach depths of more than one meter and require heavy tractors that exert high pressure on the *** of the ways to try to minimize the effect of this compaction is by retaining harvest *** objective of this study was to evaluate the impacts of eucalyptus harvesting on soil physical attributes,as well as to determine the potential of different types of residue management to reduce compaction from the soil tillage *** experiments were conducted in the same area with a Yellow *** the first experiment,compaction caused by mechanized harvesting with harvester+forwarder was *** the second experiment,different managements of harvest residues were examined as potential modifiers of soil compaction during tillage for new *** this,three managements systems were tested:(1)retention of all harvest residues and litter from the previous rotation(HR+L),(2)retention of litter from the previous rotation(L),and(3)removal of harvest residues and litter from the previous rotation(WR).Before and after harvest,sampling was carried out in the planting rows and inter-rows,and after tillage,samples were collected in the traffic line of the subsoiler-tractor *** both experiments,undisturbed soil samples were collected from the center of the 0-10,10-20,20-40,40-60,and 60-100 cm layers to determine soil density and total *** each period and site of evaluation,mechanical resistance to penetration up to the 60-cm depth was also *** harvesting operation increased soil density at 0-10 and 60-100 cm depths only in the *** of harvest residues and litter(HR+L)after harvesting avoi

关键词： Soil penetration resistance Harvester+forwarder Soil tillage Soil density Cohesive soils

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Discovery of New Terms Associated with the Navier-Stokes Momentum Balance Equation and Finding the Evidence of Its Inapplicability to Govern Fluid Flow in the Infinite Space

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Journal of Applied Mathematics and Physics 2022年第3期10卷 731-771页

作者： Nikolai Kislov Nano CVD company Tampa Florida USA

Our modeling fluid flow, especially if the fluid is referred to as a gas, is established on mimicking each particle/molecule’s movement and then gathering that movement into macro quantities characterizing the fluid flow. It has resulted in discovering a new principle of the property (mass, momentum, and energy) balance in space. We named it the Ballistic Principle of the Property Balance in Space as described earlier in our publications. This paper uses a different scheme of defining a net rate of total property efflux than our original paper. Using this scheme, we formulated integro-differential forms of mass balance and momentum balance equations adapted to the incompressible fluid flow (gas flow with a mass-flow velocity less than 0.3 Ma) at the non-uniform temperature in the infinite gas space. We also investigated the analytical behavior of the integro-differential equations in the region bounding the point of singularity by applying the Taylor series expansion method to transform the integro-differential mass and momentum balance equations into the corresponding vector differential equations. Then we compared them with the Navier-Stokes equations of mass and momentum conservation for an incompressible fluid. We were surprised to find that the Navier-Stokes momentum balance equation does not describe the fluid flow adequately. Particularly, it does not consider the momentum associated with the part of velocity acquired by each gas particle during its free path traveling in the body force field. Also, the Navier-Stokes momentum balance equation is silent about the influence of the temperature non-uniformity on the momentum balance. Finally, we have demonstrated that the Navier-Stokes equations are not applicable to govern fluid flow on R3 × [0, ∞).

关键词： Navier-Stokes Fluid Dynamics Fluid Flow Gas Flow Momentum Taylor Series

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Using High-Precision Remote Information for Auxiliary Design of Geophone Point

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石油地球物理勘探 2009年第1期44卷 1-8页

作者： Zhang You-yan Lei Ying-chun Ye Yong Hu Yan Luo Lun-cai Research Institute of Petroleum Exploration&Development CNPC Beijing 100083 China Geophysical Prospecting company CNPC Chuanqing Drilling Engineering Company Limited Chengdu Sichuan Province610213 China

利用高精度遥感数据(分辨率已达亚米级)提取相关信息评价检波器组合、选择有利检波器埋置位置,既可在观测系统设计阶段用于评估采集设计方案能否实施及辅助选择适当检波器组合图形,也可在外业测量前逐点优选检波器组合中心点,从而达到... 详细信息

利用高精度遥感数据(分辨率已达亚米级)提取相关信息评价检波器组合、选择有利检波器埋置位置,既可在观测系统设计阶段用于评估采集设计方案能否实施及辅助选择适当检波器组合图形,也可在外业测量前逐点优选检波器组合中心点,从而达到改善接收条件、提高观测系统的可实施性及保证地震资料采集质量的目的.利用高精度遥感数据提取相关信忠评价影响检波器接收信号质量的因素,所对应的遥感信忠主要用于三个方面的评估:①利用DEM(数字高程模型)与坡度计算检波器组合图形内的平整度与展开能力(组合展开度);②利用检波器组合区域的组内高差、坡度、湿度、地表松散度评价耦合条件的优劣程度(组合优度);③利用综合高精度正射影像与DEM提取的相关信忠划定工区内需要避让的地段及不符合HSE规范的施工禁区(可实施性).实例分析表明,通过遥感影像选择检波器组合与检波器埋置中心,提高了检波器组合内埋置点的平整度与组合展开度,对减轻野外劳动强度,提高劳动生产率,节约成本都起到了重要作用.

关键词：地震检波器远程数据高精度辅助设计信息点检波器组合扩大生产能力相关信息

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Design and Analysis of the Gemini Chain System in Dual Clutch Transmission of Automobile

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 38-45页

作者： CHENG Yabing GUO Haitao FU Zhenming WAN Nen LI Lei WANG Yang College of Mechanical Science and Engineering Jilin University Qingdao CHOHO Industry Limited company

Chain drive system is widely used in the conditions of high-speed, overload, variable speed and load, Many studies are focused on the meshing theory and wear characteristics of chain drive system, but system design, analysis, and noise characteristics of the chain drive system are weak. System design and noise characteristic are studied for a new type Gemini chain of dual-clutch automatic transmission. Based on the meshing theory of silent chain, the design parameters of the Gemini chain system are calculated and the mathematical models and dynamic analysis models of the Gemini chain system are established. Dynamic characteristics of the Gemini chain system is simulated and the contact force of plate and pin, plate and sprockets, the chain tension forces, the transmission error and the stress of plates and pins are analyzed. According to the simulation results of the Gemini chain system, the noise experiment about system is carried out. The noise values are tested at different speed and load and spectral characteristics are analyzed. The results of simulation and experimental show that the contact forces of plate and pin, plate and sprockets are smaller than the allowable stress values, the chain tension force is less than ultimate tension and transmission error is limited in 1.2%. The noise values can meet the requirements of industrial design, and it is proved that the design and analysis method of the Gemini chain system is scientific and feasible. The design and test system is built from analysis to test of Gemini chain system. This research presented will provide a corresponding theoretical guidance for the design and dynamic characteristics and noise characteristics of chain drive system.

关键词： Gemini chain system design noise characteristic dynamic characteristic transmission error

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Stability Analysis and Measure Study of Tobacco Farmers in the Mountainous Area of Western Hubei

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Asian Agricultural Research 2022年第11期14卷 21-23,30页

作者： Fanwen FENG Benfu LIU Jing HUANG Gaohang CHEN Shenghui TUO Yongjun CHEN Yong WANG Enshi Prefecture company of Hubei Provincial Tobacco Corporation Enshi 445000China

Through the investigation,this paper analyzes the important restricting factors for the tobacco farmers in Enshi Badong mountainous area from 2018 to 2021,including the age structure,the loss situation,the number of years of planting tobacco,the scale of planting tobacco and the benefit of planting *** paper puts forward some corresponding measures and suggestions,such as cultivating the team of professional tobacco farmers,establishing the team of young tobacco farmers,expanding professional services,developing"tobacco plus"diversified industries,and popularizing suitable agricultural machinery in mountainous areas in order to effectively improve the stability of the team of tobacco farmers.

关键词： Mountainous area Tobacco farmers Stability Measures

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Effects of Tillage Depth on Nutrients and Microbial Communities in Tobacco-planting Soil

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Agricultural Sciences 2023年第12期14卷 1702-1715页

作者： Guanxing Shang Qibo Zou Jiamei Zhang Jing Wang Yuanbo Zhang Mingchang Liu Shihai Wang Dan Zhang Wei Wang Yiming Wang Liupanshui Branch of Guizhou Tobacco company Liupanshui China Institute of Soil Science Chinese Academy of Sciences Nanjing China

The implementation of appropriate tillage practices is of great significance for agricultural production. However, the effects of different tillage depths on soil nutrients content and microbial communities in tobacco-planting soils are still lacking systematic research. In this study, three different tillage depths of 15 cm (T1), 20 cm (T2), and 30 cm (T3) were set up for field experiments in Liupanshui, Guizhou Province, to explore the effects of tillage depth on tobacco-planting soil nutrients and bacterial and fungal communities based on 16S rRNA and ITS sequencing and figure out the key factors affecting soil microbial communities. The results showed that T2 and T3 increased the contents of organic matter, total nitrogen, total phosphorus, available phosphorus, and available potassium in tobacco-planting soil, and increased the diversity of bacterial communities compared with T1. There was no significant difference in the structure of bacterial and fungal communities in different tillage depth treatments, but some dominant genera were significantly enriched in T2 and T3. Desulfobacter, Setophoma, Humicola, and Acremonium were significantly enriched in T2. Chthonomonas and Fusarium were significantly enriched in T3. These genera favor the decomposition of organic matter and the cycling of nutrients, and control soil pests and diseases. Redundancy analysis indicated that TP and AK were the key factors influencing the dominant genera of bacteria and fungi. This study provides a scientific basis for the selection of soil tillage depth for tobacco production in this region.

关键词： Tillage Depth Tobacco Soil Nutrients Bacterial Community Fungal Community

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Study on Chemical Characteristics of Rainfall in Tobacco-Growing Regions of Chenzhou, Hunan Province

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Agricultural Sciences 2022年第7期13卷 821-840页

作者： Xiangzhen Kong Yansong Xiao Qinyi Zhi Yahua Liao Bin He Hong Jian Juan Li Zhihui Cao Sijun Li Decheng Li Institute of Soil Science Chinese Academy of Sciences Nanjing China University of Chinese Academy of Sciences Beijing China Chenzhou Tobacco company of Hunan Province Chenzhou China Hunan Tobacco Leaf Redrying Co. Ltd. Chenzhou China Hunan Provincial company of CNTC Changsha China

In order to clarify the chemical properties of rainfall in typical tobacco areas in Chenzhou City, Hunan Province, and analyze its potential for soil and flue-cured tobacco planting, rainfall samples in 2020 were collected by rainfall instruments in Fangyuan Town and Aoquan Town of Guiyang County, and the chemical properties that are closely related to the quality of flue-cured tobacco were determined, such as pH, EC, total nitrogen (TN), nitrate nitrogen (), ammonium nitrogen () and ion concentrations (K+, Na+, Ca2+, Mg2+, , Al3+, , Cl−,). The results show that the pH values of rainfall samples at Fangyuan and Aoquan monitoring sites are in the range of 4.92 - 6.17 and 4.93 - 5.69 respectively, with an average of 5.27 and 5.27 respectively. The acid rain characteristic is very obvious, which is mainly dominated by . The variation of rainfall EC has seasonal characteristics. EC is low from January to September, in the range of 6.09 - 56.72 and 11.83 - 30.93 μS/cm respectively, besides, it is high from October to December, in the range of 102.63 - 174.60 and 25.05 - 86.37 μS/cm respectively. The annual deposition of TN was 22.19 and 20.76 kg/hm2/yr respectively, which were higher than that in the western regions with less human disturbance, but lower than or equal to that in the developed agricultural regions in eastern China. The proportion of in the annual deposition of TN was higher than that of at two monitoring sites, with an average of 56.51% and 38.86% respectively. Ammonia volatilization from agricultural activities contributed more to rainfall nitrogen content. The ratios of ammonium nitrogen to nitrate nitrogen deposition at two monitoring points were 1.84, 1.81, 1.86 and 1.34, 1.46, and 1.29 during the whole year, summer and autumn, winter and spring respectively. The ratio is higher in summer and autumn than in winter and spring. The weighted average equivalent concentratio

关键词： Rainfall Chemical Characteristics pH Nitrogen Form Ion Composition Tobacco-Growing Region Chenzhou

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Characteristics of mineral elements in shoots of three annual halophytes in a saline desert, Northern Xinjiang

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Journal of Arid Land 2013年第2期5卷 244-254页

作者： Ke ZHANG ChunJian LI ZhongShao LI FuHai ZHANG ZhenYong ZHAO ChangYan TIAN Key Laboratory of Oasis Ecology and Desert Environment Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences College of Resources and Environmental Sciences China Agricultural University Xinjiang Oilfield Water Supply company

Halophytes are valuable salt-, alkali- and drought-resistant germplasm resources. However, the char- acteristics of mineral elements in halophytes have not been investigated as intensively as those in crops. This study attempted to investigate the characteristics of mineral elements for annual halophytes during their growth period to reveal their possible physiological mechanisms of salt resistance. By using three native annual halophytes （Salsola subcrassa, Suaeda acuminate and Petrosimonia sibirica） distributed in the desert in Northern Xinjiang of China, the dynamic changes in the mineral element contents of annual halophytes were analyzed through field sampling and laboratory analyses. The results demonstrated that the annual halophytes were able to absorb water and mineral nutrients selectively. In the interaction between the annual halophytes and saline soil, the adaptability of the annual halophytes was manifested as the accumulation of S, Na and CI during the growth period and maintenance of water and salt balance in the plant, thus ensuring their selective absorption of N, P, K, Ca, Mg and other mineral nutrients according to their growth demand. By utilizing this property, halophyte planting and mowing （before the wilting and death periods） could bioremediate heavy saline-alkali soil.

关键词： annual halophyte mineral elements desert saline-alkali soil Northern Xinjiang

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Evaluation of Potential Productivity of Woody Energy Crops on Marginal Land in China

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Chinese Geographical Science 2017年第6期27卷 963-973页

作者： WANG Jinzhu GAO Ming HE Xinhua ZHANG Qian Natamba LEO XU Chang College of Resources and Environment Southwest University Chongqing 400715 China School of Surveying and Urban Spatial Information Henan University of Urban Construction Pingdingshan 467036 China Chongqing Municipal Tobacco company Chongqing 400715 China

Energy crops are a basic material in the bioenergy industry, and they can also mitigate carbon emissions and have environmental benefits when planted on marginal lands. The aim of this study was to evaluate the potential productivity of energy crops on marginal lands in China. A mechanistic model, combined with energy crop and land use characteristics, and meteorological and soil parameters, was used to simulate the potential productivity of energy crops. There were three main results. 1) The total marginal land in China was determined to be 104.78 × 10~6 ha. The 400-mm precipitation boundary line, which is the dividing line between the semi-humid and semi-arid zones in China, also divided the marginal land into shrub land and sparse forest land in the southeast and bare land, bare rock land, and saline alkali land in the northeast. 2) The total area of the marginal land suitable for planting energy crops was determined to be 55.82 × 10~6 ha, with Xanthoceras sorbifolia and Cerasus humilis mainly grown in the northern China, Jatropha curcas and Cornus wilsoniana mainly grown in the southwest and southeast, and Pistacia chinensis mainly grown in the central area, while also having a northeast-southwest zonal distribution. 3) Taking the highest yield in overlapping areas, the potential productivity of target energy crops was determined to be 32.63 × 10~6 t/yr. Without considering the overlapping areas, the potential productivity was 6.81 × 10~6 t/yr from X. sorbifolia, 8.86 × 10~6 t/yr from C. humilis, 7.18 × 10~6 t/yr from J. curcas, 9.55 × 10~6 t/yr from P. chinensis, and 7.78 × 10~6 t/yr from C. wilsoniana.

关键词：作物生产潜力能源作物土地利用中国潜力评价损坏木本潜在生产力

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