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Development of the electric automatic steering system for agricultural vehicles

International Journal of agricultural and Biological Engineering 2024年第1期17卷 209-214页

作者： Guangshun An Chong Yu Juan Du Xiang Yin Youliang Ni Chengqian Jin School of agricultural Engineering and Food Science Shandong University of TechnologyZibo 255000ShandongChina Nanjing research institute for agricultural mechanization of Ministry of Agriculture and Rural Affairs Nanjing 210014China

Automatic guidance of agricultural vehicles requires automatic execution of operation commands received from the navigation controller by using electronically controlled mechanisms for wheel steering,speed changing and work *** steering contributes as a prerequisite technique in automatic and semi-automatic agricultural *** research aimed to develop an electric automatic steering system that was compact in its structure and integrated into original steering mechanism in a simply and convenient way for aftermarket modification.A brushless motor and reducer assembly was utilized to provide an adequate steering torque instead of manual maneuver.A rapid assembling approach was proposed by passing the steering shaft through the hollow output shaft.A digital proportional-integral-differential(PID)algorithm was implemented to calculate the rotation speeds and directions by comparing the desired angle and the actual angle,which was implemented in a printed circuit board with a microcontroller unit(MCU)and interface *** unmanned wheeled tractor was applied as test platform to integrate the newly developed electric automatic steering *** were conducted to evaluate its performance in terms of stability and *** autonomous navigation system guided the tractor along target paths in the field by sending steering commands to the electric automatic steering *** results show that the steering angle error was less than 0.81°when desired steering angle was less than 10°.The lateral error difference was no more than 4.76 cm when repeating following the same target path,which indicated that the electric automatic steering system responded accurately and robustly to steering commands.

关键词： automatic steering automatic navigation agricultural vehicles

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Priority effects of forbs arriving early:the role of root interaction and asymmetric competition

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Ecological Processes 2024年第1期13卷 53-65页

作者： Xiaohong Yan Xiliang Li Ke Jin institute of Grassland research Chinese Academy of Agricultural Sciences

Background The priority effect of plant arrival is a key driver of community assembly and ecosystem succession during the restoration of degraded plant communities. However, the significance of the arrival order of different plant functional groups and their interactions with community assemblies remains unclear. Using a phytotron experiment with three fully crossed factors, we investigated the underlying mechanisms of priority effects and their relationships with the biomass and biodiversity effects in mixed plant communities by manipulating the order of arrival of species, isolation of roots, and removal of specific *** The results showed that the strength and direction of priority effects were influenced by arrival order, root interactions, asymmetric competition among species, and their interactions. The identities of early and late-sown species also determined the magnitude of priority effects. The priority effects were stronger in grass-first(24.76%) and legume-first communities(24.48%) than in forb-first communities. The pot biomass of the different priority treatments was highest in grass-first(5.85 g), followed by legume-first(3.94 g) and forb-first(2.48 g). The order of arrival in the mixture significantly affected the net biodiversity effects(P < 0.001), which were driven by dominance effects. The community had lower overall biomass when forbs were sown first, whereas the species grown later had fewer costs with an increased overall net benefit for the resulting *** Our results emphasize that root interactions and asymmetric competition are vital determinants of order-specific priority effects in community assemblies. In addition, the importance of the priority effect of forbs sown first is related to community assembly, which may be a key determinant in successfully establishing a highly diverse community in the early stages of restoration. Species with weak competition should be considered in the early stage of community ass

关键词： Community assembly Order of arrival Overyielding Plant functional group Root isolation

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Review of the field environmental sensing methods based on multi-sensor information fusion technology

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International Journal of agricultural and Biological Engineering 2024年第2期17卷 1-13页

作者： Yuanyuan Zhang Bin Zhang Cheng Shen Haolu Liu Jicheng Huang Kunpeng Tian Zhong Tang Nanjing institute of agricultural mechanization Ministry of Agriculture and Rural AffairsNanjing 210014China School of Mechanical Engineering Southeast UniversityNanjing 211189China School of agricultural Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

Field environmental sensing can acquire real-time environmental information,which will be applied to field operation,through the fusion of multiple ***-sensor fusion refers to the fusion of information obtained from multiple sensors using more advanced data processing *** main objective of applying this technology in field environment perception is to acquire real-time environmental information,making agricultural mechanical devices operate better in complex farmland environment with stronger sensing ability and operational *** this paper,the characteristics of sensors are studied to clarify the advantages and existing problems of each type of sensors and point out that multiple sensors can be introduced to compensate for the information ***,the mainstream information fusion types at present are *** characteristics,advantages and disadvantages of different fusion methods are *** important studies and applications related to multi-sensor information fusion technology published at home and abroad are ***,the existing problems in the field environment sensing at present are summarized and the prospect for future of sensors precise sensing,multi-dimensional fusion strategies,discrepancies in sensor fusion and agricultural information processing are proposed in hope of providing reference for the deeper development of smart agriculture.

关键词： multi-sensor information fusion field environmental sensing fusion methods smart agriculture

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Mechanism and experimental study on the fruit detachment of Chinese wolfberry through reciprocating vibration

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International Journal of agricultural and Biological Engineering 2024年第2期17卷 47-58页

作者： Song Mei Jinpeng Wang Zhiyu Song Dunbing Tang Cheng Shen College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Nanjing research institute for agricultural mechanization Ministry of Agriculture and Rural AffairsNanjing 210014China Nanjing Forestry University Nanjing 210037China

In order to realize the efficient and high-quality mechanical picking for Chinese wolfberry,firstly,the forced reciprocating vibration picking principle of the Chinese wolfberry branch was studied,and the mechanical model of vibration picking was established based on the simplified cantilever model,and the response analysis and solution of all positions for the branch were carried *** the same time,the critical mechanical model of fruit detachment under the condition of fruit hanging on branches was established,and the theoretical values of inertia force for each component of the branch were ***,through actual measurement and finite element modeling,the natural frequency and forced vibration response simulation for each component of the branch of Chinese wolfberry terminal branch model were both studied,and the relationship between single-point periodic excitation force and high-quality fruit shedding parameters was ***,according to the conclusion of the picking model,a test bench with many groups of adjustable parameters was ***,the last branch of fruit-hanging Chinese wolf berry for Ningqi No.1 was taken as the experimental object,a four-level orthogonal experiment was designed with three factors:frequency,amplitude and entrance ***,the net picking rate,damage rate and false picking rate were taken as the evaluating indicators,referring to the comprehensive scores of the three *** was concluded that the primary and secondary relations of factors affecting the picking effect are frequency,amplitude and entrance angle,and the best operation parameters are frequency of 20 Hz,amplitude of 15 mm,and entrance angle of 45°,then,a hand-held vibration picker with setting parameters was trial-produced,and the optimal parameter combination was verified in the Chinese wolfberry planting base of the National Chinese wolfberry Engineering and Technology research *** results showed that the net picking rate of rip

关键词： Chinese wolfberry branches reciprocating vibration inertial force orthogonal experiment

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Temporal and spatial evolution of global major grain trade patterns

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Journal of Integrative Agriculture 2024年第3期23卷 1075-1086页

作者： Ziqi Yin Jiaxuan Hu Jing Zhang Xiangyang Zhou Lingling Li Jianzhai Wu agricultural Information institute Chinese Academy of Agricultural SciencesBeijing 100081China institute of Scientific and Technical Information of China Beijing 100038China Zibo agricultural Science research institute Zibo 255000China Zibo institute for Digital Agriculture and Rural research Zibo 255000China

The complex and volatile international landscape has significantly impacted global grain supply security. This study uses a complex network analysis model to examine the evolution and trends of the global major grain trade from 1990 to 2020, focusing on network topology, centrality ranking, and community structure. There are three major findings. First, the global major grain trade network has expanded in scale, with a growing emphasis on diversification and balance. During the study period, the United States, Canada, China, and Brazil were the core nodes of the network. Grain-exporting countries were mainly situated in Asia, the Americas, and Europe, and importing countries in Asia, Africa, and Europe. Second, a significant increase in the number of high centrality countries with high export capacity occurred, benefiting from natural advantages such as fertile land and favorable climates. Third, the main global grain trade network is divided into four communities, with the Americas-Europe community being the largest and most widespread. The formation of the community pattern was influenced by geographic proximity, driven by the core exporting countries. Therefore, the world needs to enhance the existing trade model, promote the multi-polarization of the grain trade network, and establish a global vision for the future community. Countries and regions should participate actively in global grain trade security governance and institutional reform, expand trade links with other countries, and optimize import and export policies to reduce trade risks.

关键词： grain trade pattern evolution complex network

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Evaluation of soil loss severity and ecological restoration approach for sustainable agriculture in the Hindu Kush, Karakoram and Himalaya region

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Journal of Mountain Science 2024年第5期21卷 1509-1521页

作者： Arshad ASHRAF Imran AHMAD Climate Energy and Water Research InstituteNational Agricultural Research Centre(NARC)Islamabad 44000Pakistan

Soil erosion has resulted in removal of the topsoils containing fine soil particles and plant nutrients, causing decrease in soil fertility in the Hindu Kush, Karakoram and Himalaya(HKH) region. The existing production of cereal crop grains has been reduced to one third of the potential crop grains production owing to land degradation and poor farming practices. It is necessary to assess risk of soil loss and identify appropriate controlling measures to address issues of low agriculture productivity and water insecurity in the region. In the present study, severity of soil loss was predicted using Revised Universal Loss Equation(RUSLE) and ecological measures were identified for sustainable mountain agriculture in the HKH region of Upper Indus Basin, Pakistan. Overall 62.6% area was found to have very low risk of soil loss, i.e., 100 t/(ha·yr) in about 6.8% and 7.4% areas respectively. The mean rate of soil loss was about 41.9 t/(ha·yr) in the Hindu Kush, 31.1 t/(ha·yr) in the Himalayas, 18.8 t/(ha·yr) in the Karakoram and overall 29.7 t/(ha·yr) in the three HKH ranges. As such no considerable measures have been adopted by the communities for restoration of the degraded areas except raising fruit/farm trees and supporting limited social forestry for their livelihoods. The slopes cleared for cultivation and susceptible to erosion may be stabilized through sowing/planting of multi-purpose plant species and formation of proper bench terraces. The conservation of forest ecosystem and pastures at higher elevations would help in reducing overland water flow, risk of flash flood hazard and minimizing sediment loads in the downstream. It is essential to adopt site-specific resource conservation techniques and restore possible ecosystem health for sustainable agriculture and economic developm

关键词： Climate change Erodibility Indus basin Land degradation Slope stabilization

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Towards cultivar-oriented gene discovery for better crops

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The Crop Journal 2024年第3期12卷 670-675页

作者： Dengcai Liu Triticeae research institute Sichuan Agricultural UniversityChengdu 611130SichuanChina

The continued expansion of the world population,increasingly inconsistent climate and shrinking agricultural resources present major challenges to crop ***,the increasing ability to discover and manipulate genes creates new opportunities to develop more productive and resilient *** genes have been described in papers as being beneficial for yield ***,few of them have been translated into increased yield on *** contrast,commercial breeders are facing gene decidophobia,i.e.,puzzled about which gene to choose for breeding among the many identified,a huge chasm between gene discovery and cultivar *** purpose of this paper is to draw attention to the shortfalls in current gene discovery research and to emphasise the need to align with cultivar *** methodology dictates that genetic studies not only focus on gene discovery but also pay good attention to the genetic backgrounds,experimental validation in relevant environments,appropriate crop management,and data *** close of the gaps should accelerate the application of molecular study in breeding and contribute to future global food security.

关键词： Cultivar innovation Data reusability Gene discovery Gene decidophobia Omnigenic model

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Effects of 1-methylcyclopropene on skin greasiness and quality of'Yuluxiang'pear during storage at 20℃

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Journal of Integrative Agriculture 2024年第7期23卷 2476-2490页

作者： Wanting Yu Xinnan Zhang Weiwei Yan Xiaonan Sun Yang Wang Xiaohui Jia research institute of Pomology Chinese Academy of Agricultural SciencesXingcheng 125100China

During storage at 20℃,specific pear cultivars may exhibit a greasy texture and decline in quality due to fruit *** these varieties,‘Yuluxiang’is particularly susceptible to peel greasiness,resulting in significant economic ***,there is an urgent need for a preservative that can effectively inhibit the development of *** studies have demonstrated the efficacy of 1-methylcyclopropene(1-MCP)in extending the storage period of *** hypothesize that it may also influence the occurrence of postharvest peel greasiness in the‘Yuluxiang’*** this study,we treated‘Yuluxiang’pears with *** stored them at 20℃while analyzing the composition and morphology of the surface waxes,recording enzyme activities related to wax synthesis,and measuring indicators associated with fruit storage quality and physiological *** results demonstrate that prolonged storage at 20℃leads to a rapid increase in skin greasiness,consistent with the observed elevations in L^(*),greasiness score,and the content of total wax and greasy wax ***,there were indications that cuticular waxes underwent melting,resulting in the formation of an amorphous *** comparison to controls,the application of 1-MCP significantly inhibited increments in L^(*) values as well as grease scores while also reducing accumulation rates for oily waxes throughout most stages over its shelf period,additionally delaying transitions from flaky-wax structures towards their amorphous *** the initial 7 d of storage,several enzymes involved in the biosynthesis and metabolism of greasy wax components,including lipoxygenase(LOX),phospholipase D(PLD),andβ-ketoacyl-CoA synthase(KCS),exhibited an increase followed by a subsequent *** activity of LOX during early shelf life(0–7 d)and the KCS activity during middle to late shelf life(14–21 d)were significantly suppressed by ***,1-MCP effectively maintained firmness,

关键词： ‘Yuluxiang’pear skin greasiness 1-methylcyclopropene storage quality

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Advances in DNA methylation and its role in cytoplasmic male sterility in higher plants

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Journal of Integrative Agriculture 2024年第1期23卷 1-19页

作者： Atiqur Rahman Hasan Sofiur Rahman Shakil Uddin Naima Sultana Shirin Akhter Ujjal Kumar Nath Shamsun Nahar Begum Mazadul Islam Afroz Naznin Nurul Amin Sharif Ahmed Akbar Hossain Department of Genetics and Plant Breeding Bangladesh Agricultural UniversityMymensingh 2202Bangladesh Plant Breeding Division Bangladesh Institute of Nuclear AgricultureMymensingh 2202Bangladesh Tuber Crop research Centre Bangladesh Agricultural Research Institute(BARI)Joydebpur 1701Bangladesh Horticulture research Centre Bangladesh Agricultural Research Institute(BARI)Joydebpur 1701Bangladesh Biotechnology Division Bangladesh Agricultural Research Institute(BARI)Joydebpur 1701Bangladesh International Rice research institute Bangladesh OfficeDhaka 1213Bangladesh Division of Soil Science Bangladesh Wheat and Maize Research InstituteDinajpur 5200Bangladesh

The impact of epigenetic modifications like DNA methylation on plant phenotypes has expanded the possibilities for crop *** methylation plays a part in the regulation of both the chromatin structure and gene expression,and the enzyme involved,DNA methyltransferase,executes the methylation process within the plant *** regulating crucial biological pathways,epigenetic changes actively contribute to the creation of the ***,epigenome editing may assist in overcoming some of the drawbacks of genome editing,which can have minor off-target consequences and merely facilitate the loss of a gene’s *** drawbacks include gene knockout,which can have such off-target *** review provides examples of several molecular characteristics of DNA methylation,as well as some plant physiological processes that are impacted by these epigenetic changes in the *** also discuss how DNA alterations might be used to improve crops and meet the demands of sustainable and environmentally-friendly farming.

关键词： DNA methylation epigenetics CMS male sterility chromatin architecture gene expression higher plants

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Identification and fine mapping of qSW2 for leaf slow wilting in soybean

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The Crop Journal 2024年第1期12卷 244-251页

作者： Shengyou Li Changling Wang Chunjuan Yan Xugang Sun Lijun Zhang Yongqiang Cao Wenbin Wang Shuhong Song institute of Crop research Liaoning Academy of Agricultural SciencesShenyang 110161LiaoningChina

Drought is one of the abiotic stresses limiting the production of soybean(Glycine max).Elucidation of the genetic and molecular basis of the slow-wilting(SW)trait of this crop offers the prospect of its genetic improvement.A panel of 188 accessions and a set of recombinant inbred lines produced from a cross between cultivars Liaodou 14 and Liaodou 21 were used to identify quantitative-trait loci(QTL)associated with *** were genotyped by Specific-locus amplified fragment sequencing and seedling leaf wilting was assessed under three water-stress treatments.A genome-wide association study identified 26 SW-associated single-nucleotide polymorphisms(SNPs),including three located in a 248-kb linkage-disequilibrium(LD)block on chromosome *** mapping revealed a major-effect QTL,qSW2,associated with all three treatments and adjacent to the LD *** mapping in a BC_(2)F_(3) population derived from a backcross between Liaodou 21 and R26 confined qSW2 to a 60-kb *** expression and sequence variation analysis identified the gene Glyma.02 g218100,encoding an auxin transcription factor,as a candidate gene for *** results will contribute significantly to improving drought-resistant soybean cultivars by providing genetic information and resources.

关键词： Drought GWAS Linkage mapping Slow wilting Soybean(Glycine max)

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