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Developing sustainable summer maize production for smallholder farmers in the North China Plain: An agronomic diagnosis method

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Journal of Integrative Agriculture 2019年第8期18卷 1667-1679页

作者： CHEN Guang-feng CAO Hong-zhu CHEN Dong-dong ZHANG Ling-bo ZHAO Wei-li ZHANG Yu MA Wen-qi JIANG Rong-feng ZHANG Hong-yan ZHANG Fu-suo College of Resources and Environmental Sciences China Agricultural University Beijing 100193 P.R.China College of Resources and Environment Science Hebei Agricultural University Baoding 071001 P.R.China Key Laboratory of Plant-Soil Interactions Ministry of Education Beijing 100193 P.R.China National Agricultural Technology extension and service Center Ministry of Agriculture and Rural Affairs Beijing 100125 P.R.C hina

With an increasing population and changing diet structure, summer maize is increasingly becoming an important energy crop in China. However, traditional farmer practices for maize production are inefficient and unsustainable. To ensure food security and sustainable development of summer maize production in China, an improved, more sustainable farmer management system is needed. Establishing this system requires a comprehensive understanding of the limitations of current farming practice and the ways it could be improved. In our study, 235 plots from three villages in the North China Plain(NCP) were monitored. Maize production on farms was evaluated;our results showed that the maize yield and nitrogen partial factor productivity(PFPN) were variable on smallholder farms at 6.6–13.7 t ha^–1 and 15.4–88.7 kg kg^–1, *** farming practices also have a large environmental impact(nitrogen surplus:–64.2–323.78 kg ha^–1). Key yield components were identified by agronomic diagnosis. Grain yield depend heavily on grain numbers per hectare rather than on the 1 000-grain weight. A set of improved management practices(IP) for maize production was designed by employing a boundary line(BL) approach and tested on farms. Results showed that the IP could increase yield by 18.4% and PFPN by 31.1%, compared with traditional farmer practices(FP), and reduce the nitrogen(N) surplus by 57.9 kg ha^–1. However,in terms of IP effect, there was a large heterogeneity among different smallholder farmers’ fields, meaning that, precise technologies were needed in different sites especially for N fertilizer management. Our results are valuable for policymakers and smallholder farmers for meeting the objectives of green development in agricultural production.

关键词： smallholder farmers sustainable production yield gap agronomic diagnosis North China Plain

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Four buildings and a flush:Lessons from degraded water quality and recommendations on building water management

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Environmental Science and Ecotechnology 2024年第2期18卷 104-113页

作者： Kyungyeon Ra Caitlin Proctor Christian Ley Danielle Angert Yoorae Noh Tolulope Odimayomi Andrew J.Whelton Lyles School of Civil Engineering Purdue University550 Stadium Mall DriveWest LafayetteIN47907USA Agricultural and Biological Engineering Division of Environmental and Ecological EngineeringPurdue UniversityWest LafayetteIN47907USA Division of Environmental and Ecological Engineering Purdue UniversityWest LafayetteIN47907USA Civil and Environmental Engineering University of Colorado1111 Engineering DriveBoulderCO80309USA Civil Architectural and Environmental EngineeringUniversity of Texas301E E Dean Keeton StreetAustinTX78712USA Civil and Environmental Engineering Virginia Tech750 Drillfield DriveBlacksburgVA24061USA Lyles School of Civil Engineering Division of Environmental and Ecological EngineeringPurdue University550 Stadium Mall DriveWest LafayetteIN47907USA

A reduction in building occupancy can lead to stagnant water in plumbing,and the potential consequences for water quality have gained increasing *** investigate this,a study was conducted during the COVID-19 pandemic,focusing on water quality in four institutional *** of these buildings were old(>58 years)and large(>19,000 m2),while the other two were new(>13 years)and small(service line to the *** the absence of this knowledge,building owners should create and use as-built drawings to develop flushing plans and conduct periodic water testing.

关键词： COVID-19 pandemic Stagnation Drinking water quality Flushing

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Genomic analysis,trajectory tracking,and field surveys reveal sources and long-distance dispersal routes of wheat stripe rust pathogen in China

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Plant Communications 2023年第4期4卷 174-188页

作者： Yuxiang Li Jichen Dai Taixue Zhang Baotong Wang Siyue Zhang Conghao Wang Jiguang Zhang Qiang Yao Mingju Li Chengyun Li Yuelin Peng Shiqin Cao Gangming Zhan Fei Tao Haifeng Gao Weili Huang Xiaojun Feng Yingwen Bai Zhuoma Qucuo Hongsheng Shang Chong Huang Wancai Liu Jiasui Zhan Xiangming Xu Xianming Chen Zhensheng Kang Xiaoping Hu State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection Northwest A&F UniversityTaicheng Road 3YanglingShaanxiChina KeyLaboratory of Agricultural Integrated PestManagement Qinghai ProvinceAcademyof Agriculture and ForestryScienceQinghai UniversityXiningQinghaiChina Yunnan Key Laboratory of Green Prevention and Control of Agricultural Transboundary Pests Agricultural Environment and Resource InstituteYunnan Academy of Agricultural SciencesKunmingYunnanChina State Key Laboratory for Conservation and Utilization of Bio-resources in Yunnan Yunnan Agricultural UniversityKunmingYunnanChina Department of Plant Pathology Tibet Agricultural and Animal Husbandry CollegeLinzhiTibetChina Wheat Research Institute Gansu Academy of Agricultural SciencesLanzhouGansuChina Biocontrol Engineering Laboratory of Crop Diseases and Pests of Gansu Province College of Plant ProtectionGansu Agricultural UniversityLanzhouGansuChina Institute of Plant Protection Xinjiang Academy of Agricultural SciencesUrumqiXinjiangChina Xi’an Huang’s Bio-technology Company Ltd Xi’anShaanxiChina Shaanxi Plant Protection extension Station Xi’anShaanxiChina Baoji Plant Protection extension Station BaojiShaanxiChina National Agricultural Technology extension and service Center Ministry of AgricultureBeijingChina Department of Forest Mycology and Plant Pathology Swedish University of Agricultural SciencesUppsalaSweden Pest&Pathogen Ecology NIAB EMREast MallingWest MallingKentUK Agricultural Research service United States Department of Agriculture and Department of Plant PathologyWashington State UniversityPullmanWAUSA

Identifying sources of phytopathogen inoculum and determining their contributions to disease outbreaks are essential for predicting disease development and establishing control *** striiformis ***(Pst),the causal agent of wheat stripe rust,is an airborne fungal pathogen with rapid virulence variation that threatens wheat production through its long-distance *** of wide variation in geographic features,climatic conditions,and wheat production systems,Pst sources and related dispersal routes in China are largely *** the present study,we performed genomic analyses of 154 Pst isolates from all major wheat-growing regions in China to determine Pst population structure and *** trajectory tracking,historical migration studies,genetic introgression analyses,and field surveys,we investigated Pst sources and their contributions to wheat stripe rust *** identified Longnan,the Himalayan region,and the Guizhou Plateau,which contain the highest population genetic diversities,as the Pst sources in *** from Longnan disseminates mainly to eastern Liupan Mountain,the Sichuan Basin,and eastern Qinghai;that from the Himalayan region spreads mainly to the Sichuan Basin and eastern Qinghai;and that from the Guizhou Plateau migrates mainly to the Sichuan Basin and the Central *** findings improve our current understanding of wheat stripe rust epidemics in China and emphasize the need for managing stripe rust on a national scale.

关键词： Puccinia striiformis f.sp.tritici stripe rust disease epidemics population genetics genome sequencing

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A Machine Learning-Based Distributed Denial of service Detection Approach for Early Warning in Internet Exchange Points

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Computers, Materials & Continua 2023年第8期76卷 2235-2259页

作者： Salem Alhayani Diane R.Murphy School of Technology and Innovation College of Business InnovationLeadershipand Technology(BILT)Marymount UniversityArlingtonVirginia22207USA

The Internet service provider(ISP)is the heart of any country’s Internet infrastructure and plays an important role in connecting to theWorld *** exchange point(IXP)allows the interconnection of two or more separate network *** Internet traffic entering a country should pass through its ***,it is an ideal location for performing malicious traffic *** denial of service(DDoS)attacks are becoming a more serious daily *** actors in DDoS attacks control numerous infected machines known as *** are used to send numerous fake requests to overwhelm the resources of victims and make them unavailable for some *** date,such attacks present a major devastating security threat on the *** paper proposes an effective and efficient machine learning(ML)-based DDoS detection approach for the early warning and protection of the Saudi Arabia Internet exchange point(SAIXP)*** effectiveness and efficiency of the proposed approach are verified by selecting an accurate ML method with a small number of input features.A chi-square method is used for feature selection because it is easier to compute than other methods,and it does not require any assumption about feature distribution *** ML methods are assessed using holdout and 10-fold tests on a public large-size *** experiments showed that the performance of the decision tree(DT)classifier achieved a high accuracy result(99.98%)with a small number of features(10 features).The experimental results confirmthe applicability of using DT and chi-square for DDoS detection and early warning in SAIXP.

关键词： Internet exchange point Saudi Arabia IXP(SAIXP) distributed denial of service chi-square feature selection machine learning

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On generalized symmetries and structure of modular categories

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Science China Mathematics 2019年第3期62卷 417-446页

作者： Shawn Xingshan Cui Modjtaba Shokrian Zini Zhenghan Wang Stanford Institute for Theoretical Physics Stanford University Department of Mathematics Virginia Polytechnic Institute and State University Department of Mathematics University of California at Santa Barbara Microsoft Station Q

Pursuing a generalization of group symmetries of modular categories to category symmetries in topological phases of matter, we study linear Hopf monads. The main goal is a generalization of extension and gauging group symmetries to category symmetries of modular categories, which include also categorical Hopf algebras as special cases. As an application, we propose an analogue of the classification of finite simple groups to modular categories, where we define simple modular categories as the prime ones without any nontrivial normal algebras.

关键词： modular category category symmetry Hopf monad tensor functor

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Detection of Huanglongbing(citrus greening) based on hyperspectral image analysis and PCR

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Frontiers of Agricultural Science and Engineering 2019年第2期6卷 172-180页

作者： Kejian WANG Dongmei GUO Yao ZHANG Lie DENG Rangjin XIE Qiang LV Shilai YI Yongqiang ZHENG Yanyan MA Shaolan HE Southwest university/Citrus Research Institute of Chinese Academy of Agricultural Sciences Chongqing 400712 China National Agricultural Technology extension and service Center Beijing 100125 China Chengdu Plant Quarantine Station Chengdu 610000 China Key Laboratory of Modern Precision Agriculture System Integration Research China Agricultural University Beijing 100083 China

Huanglongbing (HLB, citrus greening) is one of the most serious quarantine diseases of citrus worldwide. To monitor in real-time, recognize diseased trees, and efficiently prevent and control HLB disease in citrus, it is necessary to develop a rapid diagnostic method to detect HLB infected plants without symptoms. This study used Newhall navel orange plants as the research subject, and collected normal color leaf samples and chlorotic leaf samples from a healthy orchard and an HLB-infected orchard, respectively. First, hyperspectral data of the upper and lower leaf surfaces were obtained, and then the polymerase chain reaction (PCR) was used to detect the HLB bacterium in each leaf. The PCR test results showed that all samples from the healthy orchard were negative, and a portion of the samples from the infected orchard were positive. According to these results, the leaf samples from the orchards were divided into disease-free leaves and HLB-positive leaves, and the least squares support vector machine recognition model was established based on the leaf hyperspectral reflectance. The effect on the model of the spectra obtained from the upper and lower leaf surfaces was investigated and different pretreatment methods were compared and analyzed. It was observed that the HLB recognition rate values of the calibration and validation sets based on upper leaf surface spectra under 9-point smoothing pretreatment were 100% and 92.5%, respectively. The recognition rate values based on lower leaf surface spectra under the second-order derivative pretreatment were also 100% and 92.5%, respectively. Both upper and lower leaf surface spectra were available for recognition of HLB-infected leaves, and the HLB PCR-positive leaves could be distinguished from the healthy by the hyperspectral modeling analysis. The results of this study show that early and nondestructive detection of HLBinfected leaves without symptoms is possible, which provides a basis for the hyperspectral diagnosi

关键词： citrus HLB hyperspectral identification PCR

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Exploring the impact of soil water variability and varietal diversity on alfalfa yield,nutritional quality,and farm profitability

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Grassland Research 2023年第4期2卷 266-278页

作者： Rudra Baral S.V.Krishna Jagadish Nathan Hein Romulo P.Lollato Aleksan Shanoyan Anil K.Giri Jiyung Kim Myungkyo Kim Doohong Min university of Missouri extension ColumbiaMissouriUSA Deartment of Plant and Soil Science Texas Tech UniversityLubbockTexasUSA Department of Agronomy Kansas State UniversityManhattanKansasUSA Department of Agricultural Economics Kansas State UniversityManhattanKansasUSA Economic Research service United States Department of AgricultureKansas CityMissouriUSA School of Business Hanyang UniversitySeoulSouth Korea

Background:Despite high nutritional and economic value,alfalfa yield has not been improved in the United *** moisture critically influences alfalfa's yield and quality,affecting its physiological processes,nutrient uptake,and stand ***,the maturity stage at harvest can significantly impact both hay yield and ***,this study aimed to assess the effect of different soil moisture levels and harvesting times on forage yield,nutritive value,and the overall profitability of commercially cultivated ***:Two conventional and three lower-lignin alfalfa varieties were planted in a randomized complete block with split plot design under drought,rainfed,and irrigation conditions in 2020 in Manhattan,Kansas,*** dry matter yield(DMY)and forage nutritive value were evaluated at late bud,early flowering,and 7 days after early flowering stages,***:DMY varied with production year,soil water availability,and growth stages,with drought conditions causing a decline in DMY of 5%to 38%in the second production *** conditions and maturity stages influenced crude protein(CP)and in vitro dry matter digestibility(IVDMD).Higher soil moisture and advancing maturity stages negatively impacted CP,IVDMD,and relative forage *** study revealed net profit margins of 62%,64%,and 52%for drought-prone,rainfed,and irrigated production,***:Harvest timing and irrigation practices were found to have substantial implications for forage yield and nutritive value of *** yield-quality trade-off differed under drought and irrigation,with early harvesting leading to lower yields but higher protein content and *** study findings provide potential guidance for improving alfalfa hay yield,quality,and profitability.

关键词： crude protein drought dry matter yield forage nutritive value irrigation net farm income rainfed relative forage quality

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Selectively unforgeable but existentially forgeable signature schemes and applications

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Science China(Information Sciences) 2013年第1期56卷 98-111页

作者： TIAN HaiBo ZHANG FangGuo CHEN XiaoFeng WEI BaoDian School of Information Science and Technology Sun Yat-Sun University State Key Laboratory of Integrated service Networks Xidian University

This paper gives definitions,constructions and applications of signature schemes,which are selectively unforgeable but existentially forgeable(SUEF).We formalize the special notion under conditions of chosen message attack(CMA) and known message attack(KMA).Then two general constructions are presented with two concrete *** apply the SUEF secure signature schemes to an elementary authentication mechanism,the challenge-response mechanism,to obtain a basic deniable authentication *** method is presented as a deniable message transmission(MT) authenticator in the extension framework of Raimondo.

关键词： signature schemes selectively unforgeable deniable authentication

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Development of a rapid and efficient system for CR genes identification based on hairy root transformation in Brassicaceae

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Horticultural Plant Journal 2024年第4期10卷 1049-1060页

作者： Wenlin Yu Lu Yang Yuanyuan Xiang Rongde Li Xueqing Zhou Longcai Gan Xianyu Xiang Yunyun Zhang Lei Yuan Yanqing Luo Genze Li Youning Wang Yinhua Chen Peng Chen Chunyu Zhang National Key Laboratory of Crop Genetic Improvement and College of Plant Science and Technology Huazhong Agricultural UniversityWuhanHubei 430070China National Key Laboratory for Tropical Crop Breeding Sanya Nanfan Research InstituteHainan UniversitySanyaHainan 572025China National Agro-Tech extension and service Center Beijing 100125China Industrial Crops Research Institute Yunnan Academy of Agricultural SciencesKunmingYunnan 650221China College ofAgronomy NorthwestA&F UniversityYanglingShaanxi712100China

Many economically important crops and vegetables belonging to the cruciferous family are heavily endangered by clubroot disease caused by Plasmodiophora brassicae *** of clubroot resistant cultivars based on mapping and cloning of resistant genes is commonly regarded as the most cost-effective and efficient way to fight against this *** traditional way of R gene functional validation requires stable transformation that is both time-and *** this study,a rapid and efficient hairy-root transgenic protocol mediated by Agrobacterium rhizogenes was *** transformation positive rate was over 80%in Brassica napus showed by GUS reporter gene and this transformation only took 1/6 of the time compared with stable *** system was applicable to different *** varieties and other cruciferous crops including Brassica rapa and Brassica *** particular,two known CR genes,CRA3.7.1 and CRA8.2.4 were used respectively,as example to show that the system works well for CR gene study combined with subsequent *** infection in *** importantly,it works both in over-expression that led to disease resistance,as well as in RNAi which led to disease susceptible ***,this system can be used in batch-wise identification of CR genes,and also offered the possibility of manipulating key genes within the *** genome that could improve our knowledge on host-pathogen interaction.

关键词： Brassicaceae Agrobacterium rhizogenes Hairy root transformation Clubroot Gene function

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IMPACT OF ATMOSPHERIC LOW-FREQUENCY OSCILLATION ON THE IMMIGRATION OF NILAPARVATA LUGENS(STL) IN HUNAN AND JIANGXI PROVINCES

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Journal of Tropical Meteorology 2018年第2期24卷 209-219页

作者： SUN Si-si BAO Yun-xuan ZHENG Teng-fei LU Ming-hong XIE Xiao-jin Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Key Laboratory of Agricultural Meteorology in Jiangsu ProvinceNanjing University of Information Science ＆ TechnologyNanjing 210044 China Guangzhou Institute of Tropical and Marine Meteorology/Guangdong Provincial Key Laboratory of Regional Numerical Weather Prediction CMAGuangzhou 510080 China National Agricultural Technology extension and service Center Ministry of AgricultureBeijing 100081 China

Various features of the atmospheric environment affect the number of migratory insects, besides their initial population. However, little is known about the impact of atmospheric low-frequency oscillation(10 to 90 days) on insect migration. A case study was conducted to ascertain the influence of low-frequency atmospheric oscillation on the immigration of brown planthopper, Nilaparvata lugens(Stl), in Hunan and Jiangxi provinces. The results showed the following:(1) The number of immigrating N. lugens from April to June of 2007 through 2016 mainly exhibited a periodic oscillation of 10 to 20 days.(2) The 10-20 d low-frequency number of immigrating N. lugens was significantly correlated with a low-frequency wind field and a geopotential height field at 850 h Pa.(3) During the peak phase of immigration, southwest or south winds served as a driving force and carried N. lugens populations northward, and when in the back of the trough and the front of the ridge, the downward airflow created a favorable condition for N. lugens to land in the study area. In conclusion, the northward migration of N. lugens was influenced by a low-frequency atmospheric circulation based on the analysis of dynamics. This study was the first research connecting atmospheric low-frequency oscillation to insect migration.

关键词： atmospheric low-frequency oscillation Nilaparvata lugens (St/il) immigrating number cycle of 10-20 days atmospheric circulation

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