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Lignin engineering in forest trees: From gene discovery to field trials

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Plant Communications 2022年第6期3卷 1-25页

作者： Barbara De Meester Ruben Vanholme Thatiane Mota Wout Boerjan Ghent University Department of Plant Biotechnology and BioinformaticsTechnologiepark 719052 GhentBelgium VIB Center for Plant Systems Biology Technologiepark 719052 GhentBelgium

Wood is an abundant and renewable feedstock for the production of pulp,fuels,and biobased ***,wood is recalcitrant toward deconstruction into cellulose and simple sugars,mainly because of the presence of lignin,an aromatic polymer that shields cell-wall ***,numerous research efforts have focused on engineering lignin amount and composition to improve wood ***,we focus on results that have been obtained by engineering the lignin biosynthesis and branching pathways in forest trees to reduce cell-wall recalcitrance,including the introduction of exotic lignin *** addition,we draw general conclusions from over 20 years of field trial research with trees engineered to produce less or altered *** discuss possible causes and solutions for the yield penalty that is often associated with lignin engineering in ***,we discuss how conventional and new breeding strategies can be combined to develop elite clones with desired lignin *** conclude this review with priorities for the development of commercially relevant lignin-engineered trees.

关键词： lignin genetic engineering breeding CRISPR field trial forest trees

Detection of biosignatures in Terrestrial analogs of Martian regions:Strategical and technical assessments

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Earth and Planetary Physics 2022年第5期6卷 431-450页

作者： JianXun Shen Yan Chen Yu Sun Li Liu YongXin Pan Wei Lin Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

For decades, the search for potential signs of Martian life has attracted strong international interest and has led to significant planning and scientific implementation. Clearly, in order to detect potential life signals beyond Earth, fundamental questions, such as how to define such terms as “life” and “biosignature”, have been given considerable attention. Due to the high costs of direct exploration of Mars, Mars-like regions on Earth have been invaluable targets for astrobiological research, places where scientists could practice the search for “biosignatures” and refine ways to detect them. This review summarizes scientific instrumental techniques that have resulted from this work. Instruments must necessarily be our “eyes” and “hands” as we attempt to identify and quantify biosignatures on *** devices that can be applied in astrobiology include mass spectrometers and electromagnetic-spectrum-based spectrometers,redox potential indicators, circular dichroism polarimeters, in situ nucleic acid sequencers, life isolation/cultivation systems, and *** devices and how to interpret the data they collect have been tested in Mars-analog extreme environments on Earth to validate their practicality on Mars. To anticipate the challenges of instrumental detection of biosignatures through the full evolutionary history of Mars, Terrestrial Mars analogs are divided into four major categories according to their similarities to different Martian geological periods(the Early-Middle Noachian Period, the Late Noachian-Early Hesperian Period, the Late Hesperian-Early Amazonian Period, and the Middle-Late Amazonian Period). Future missions are suggested that would focus more intensively on Mars’ Southern Hemisphere, once landing issues there are solved by advances in spacecraft engineering, since exploration of these early terrains will permit investigations covering a wider continuum of the shifting habitability of Mars through its geological history. Finally,

关键词： biosignature detection framework extraterrestrial life evolutionary history of Mars field trial instrument Mars analog

Removal of metals by sorghum plants from contaminated land

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Journal of Environmental Sciences 2009年第10期21卷 1432-1437页

作者： ZHUANG Ping SHU Wensheng LI Zhian LIAO Bin LI Jintian SHAO Jingsong Institute of Ecology South China Botanic Garden Chinese Academy of Sciences Guangzhou 510560 China. School of Life Sciences and State Key Laboratory of Biocontrol Sun Yat-sen University Guangzhou 510275 China

The growth of high biomass crops facilitated by optimal of agronomic practices has been considered as an alternative to phytoremediation of soils contaminated by heavy metals. A field trial was carded out to evaluate the phytoextraction efficiency of heavy metals by three varieties of sweet sorghum （Sorghum biocolor L.）, a high biomass energy plant. Ethylene diamine tetraacetate （EDTA）, ammonium nitrate （NH4NO3） and ammonium sulphate （（NH4）2SO4） were tested for their abilities to enhance the removal of heavy metals Pb, Cd, Zn, and Cu by sweet sorghum from a contaminated agricultural soil. Sorghum plants always achieved the greatest removal of Pb by leaves and the greatest removal of Cd, Zn and Cu by stems. There was no significant difference among the Keller, Rio and Mray varieties of sweet sorghums in accumulating heavy metals. EDTA treatment was more efficient than ammonium nitrate and ammonium sulphate in promoting Pb accumulation in sweet sorghum from the contaminated agricultural soil. The application of ammonium nitrate and ammonium sulphate increased the accumulation of both Zn and Cd in roots of sorghum plants. Results from this study suggest that cropping of sorghum plants facilitated by agronomic practices may be a sustainable technique for partial decontamination of heavy metal contaminated soils.

关键词： Sorghum biocolor field trial phytoextraction

Nitrification inhibitor nitrapyrin does not affect yield-scaled nitrous oxide emissions in a tropical grassland

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Pedosphere 2021年第2期31卷 265-278页

作者： Ana Gabriela PÉREZ-CASTILLO Cristina CHINCHILLA-SOTO Jorge Alberto ELIZONDO-SALAZAR Ronny BARBOZA Dong-Gill KIM Christoph MÜLLER Alberto SANZ-COBENA Azam BORZOUEI Khadim DAWAR Mohammad ZAMAN Environmental Pollution Research Center(CICA) University of Costa RicaMontes de Oca 11501(Costa Rica) Alfredo Volio Mata Experimental Station University of Costa RicaOchomogo 30304(Costa Rica) Wondo Genet College of Forestry and Natural Resources Hawassa UniversityP.O.Box 128Shashemene(Ethiopia) Institute of Plant Ecology Justus Liebig University GiessenHeinrich-Buff Ring 26Giessen 35392(Germany) School of Biology and Environmental Science University College DublinBelfieldDublin 4(Ireland) Research Center for the Management of Environmental and Agricultural Risks(CEIGRAM) Department of Chemistry and Food Technology(ETSIAAB)Universidad Politécnica de MadridMadrid 28040(Spain) Nuclear Agriculture Research School Nuclear Science and Technology Research Institute(NSTRI)Karaj 31465-1498(Iran) Department of Soil and Environmental Sciences The University of AgriculturePeshawar 25000(Pakistan) Soil and Water Management&Crop Nutrition Section Joint Food and Agriculture Organization(FAO)/International Atomic Energy Agency(IAEA)Division of Nuclear Techniques in Food and AgricultureDepartment of Nuclear Sciences and ApplicationsIAEAVienna International CentreP.O.Box 100Vienna 1400(Austria)

Urea is the most common nitrogen(N)fertilizer used in the tropics but it has the risk of high gaseous nitrogen(N)*** of nitrification inhibitor has been suggested as a potential mitigation measure for gaseous N losses in N fertilizer-applied *** a field trial on a tropical Andosol pastureland in Costa Rica,gaseous emissions of ammonia(NH_(3))and nitrous oxide(N_(2)O)and grass yield were quantified from plots treated with urea(U;41.7 kg N ha^(-1)application^(-1))and urea plus the nitrification inhibitor nitrapyrin(U+NI;41.7 kg N ha^(-1)application^(-1)and 350 g of nitrapyrin for each 100 kg of N applied)and control plots(without U and NI)over a six-month period(rainy season).Volatilization of NH_(3)(August to November)in U(7.4%±1.3%of N applied)and U+NI(8.1%±0.9%of N applied)were not significantly different(P>0.05).Emissions of N_(2)O in U and U+NI from June to November were significantly different(P<0.05)only in October,when N_(2)O emission in U+NI was higher than that in *** and crude protein production of grass were significantly higher(P<0.05)in U and U+NI than in the control plots,but they were not significantly different between U and U+*** was no significant difference in yield-scaled N_(2)O emission between U(0.31±0.10 g N kg^(-1)dry matter)and U+NI(0.47±0.10 g N kg^(-1)dry matter).The results suggest that nitrapyrin is not a viable mitigation option for gaseous N losses under typical N fertilizer application practices of pasturelands at the study site.

关键词： ammonia volatilization Andosol Costa Rica field trial gaseous N loss greenhouse gas emission urea

A Revisit to the Swedish Wet Compaction Method—A Case Study of the Burvattnet Dam Reconstruction

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Open Journal of Civil Engineering 2023年第2期13卷 282-291页

作者： Hans Rönnqvist Tina Påhlstorp Daniel Gustavsson RQV Teknik AB Hudiksvall Sweden AFRY Malmö Sweden Vattenregleringsföretagen Östersund Sweden

The Swedish Wet compaction method allows soil compaction at higher water content than conventional Dry compaction methods and can be used to advantage when difficulties arise in keeping to a certain Dry compaction water content. Wet compaction was frequently applied for dam core soils of glacial till (moraine) up until late 1970s, and despite several advantages it is since no longer used in engineering practice. During the reconstruction of Burvattnet Main Dam in Sweden, the lack of dry core soil together with severe weather conditions made Dry compaction almost impossible. On the basis of laboratory compaction tests performed in compliance with the standard from the 1950s, and field compaction trials on site, this paper describes the steps taken to revisit the Wet compaction method, which made it possible to continue the filling works in keeping with the timeline of the project.

关键词： Soil Compaction Wet Compaction Laboratory field trial Glacial Till

Effect of non-aflatoxigenic strains of Aspergillus flavus on aflatoxin contamination of pre-harvest peanuts in fields in China

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Oil Crop Science 2021年第2期6卷 81-86页

作者： Liying Yan Wanduo Song Yuning Chen Yanping Kang Yong Lei Dongxin Huai Zhihui Wang Xin Wang Boshou Liao Key Laboratory of Biology and Genetics Improvement of Oil Crops Ministry of Agriculture and Rural AffairsOil Crops Research Institute of Chinese Academy of Agricultural SciencesWuhan 430062China

Aflatoxin contamination of peanuts is one of the most concerns in peanut production in *** nonaflatoxigenic Aspergillus flavus strains,based on competitive exclusion,has been proved to be a promising strategy to reduce aflatoxin contamination in pre-harvest *** non-aflatoxigenic *** strains collected in China,which have been proved effectively reducing aflatoxin in the laboratory,were mixed with high aflatoxin producer to the soil in peanut growing *** two non-aflatoxigenic strains significantly(Pfield 1,and 84.96–99.33%in field *** aflatoxin was reduced 84.96–99.33%under drought stress in two *** present study indicated the non-aflatoxigenic *** strains could be potential biocontrol agents for reducing aflatoxin contamination under field condition.

关键词： Peanut Non-aflatoxigenic Aspergillus flavus Aflatoxin reduction field trial

field Transmission of 100G and Beyond:Multiple Baud Rates and Mixed Line Rates Using Nyquist-WDM Technology

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ZTE Communications 2012年第3期10卷 28-38页

作者： Zhensheng Jia Jianjun Yu Hung-Chang Chien Ze Dong Di Huo ZTE USA MorristownNJ 07960USA

In this paper, we describe successful joint experiments with Deutsche Telecom on long-haul transmission of 100G and beyond over standard single mode fiber （SSMF） and with in-line EDFA-only amplification. The transmission link consists of 8 nodes and 950 km installed SSMF in DT＇ s optical infrastructure. Laboratory SSMF was added for extended optical reach. The first field experiment involved transmission of 8 x 216.8 Gbit/s Nyquist-WDM signals over 1750 km with 21.6 dB average loss per span. Each channel, modulated by a 54.2 Gbaud PDM-CSRZ-QPSK signal, is on a 50 GHz grid, which produces a net spectral efficiency （SE） of 4 bit/s/Hz. We also describe mixed-data-rate transmission coexisting with 1T, 400G, and 100G channels. The 400G channel uses four independent subcarriers modulated by 28 Gbaud PDM-QPSK signals. This yields a net SE of 4 bit/s/Hz, and 13 optically generated subcarriers from a single optical source are used in the 1T channel with 25 Gbaud PDM-QPSK modulation. The 100G signal uses real-time coherent PDM-QPSK transponder with 15% overhead of soft-decision forward-error correction （SD-FEC）. The digital post filter and 1 -bit maximum-likelihood sequence estimation （MLSE） are introduced at the receiver DSP to suppress noise, linear crosstalk, and filtering effects. Our results show that future 400G and 1T channels that use Nyquist WDM can transmit over long-haul distances with higher SE and using the same QPSK format.

关键词： coherent detection field trial coherent optical OFDM Nyquist WDM MLSE

field Control Effect of Biocontrol Bacteria Pseudomonas guariconensis Strain ST4 on Sugarcane Smut

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Field Control Effect of Biocontrol Bacteria Pseudomonas guar...

Seeding Performance Simulations and Experiments for a Spoon- Wheel Type Precision Cottonseed-Metering Device Based on EDEM

中国植物病理学会2019年学术年会

作者： Lin Nuoqiao Zhang Lianhui Guangdong Province Key Lab oratory of Microbial Signals and Disease Control Integrative Microbiology Research CentreSouth China Agricultural University

Sugarcane is an important cash crop in China,widely planted in Guangxi,Guangdong and Hainan *** smut,a fungal disease caused by Sporisorium scitamineum,is one of the vital diseases affecting quality and yield of *** of *** depends on the mating of bipolar sporidia to form a dikaryon and develops hyphae to penetrate the meristematic tissue of *** *** ST4,isolated from rhizosphere in Shantou city of Guangdong Province,was known to produce bioactive compounds to inhibit the mating process of *** and Ustilago maydis.A bioactive inhibitor produced by strain ST4 has been isolated and identified as an indole *** trial in greenhouse showed that control efficiency of this inhibitor on maize smut is up to 94%.In order to verify the field control effect of strain ST4 on sugarcane smut,sugarcane buds was soaked in strain ST4 solution prior to plantation in the field where the disease was serious the previous *** microbial agent was applied at the sowing stage and the tillering stage in order to compare the control effect of primary infection and re-infection of *** results showed that strain ST4 had better biocontrol effect on the re-infection of *** biennial root of sugarcane was also treated with strain *** results showed that the control effect of strain ST4 on sugarcane root was better than that of newly planted sugarcane,with biocontrol efficiency up to 76%.Optimization of treatment procedures might further improve the biocontrol efficiency.

关键词： Sugarcane smut Sporisorium scitamineum Pseudomonas guariconensis Strain ST4 field trial

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Mechanical Engineering Science 2020年第1期2卷 1-8页

作者： Yudao LI Shulun XING Shasha LI Li LIU Xiaohui ZHANG Zhanhua SONG Fade LI Shandong Agricultural University TaianShandong 271018China Shandong Provincial Key Laboratory of Horticultural Machinery and Equipment TaianShandong 271018China Shandong Provincial Engineering Laboratory of Agricultural Equipment Intelligence TaianShandong 271018China Shandong University JinanShandong 250061China

To study the effects of seed metering on seeding performance under different motion parameters,a simulation model for a spoonwheel type seeder was established.A seed meter was tested by using EDEM(Engineering Discrete Element Method)software to simulate its working process at different speeds and tilt *** trajectories of individual cottonseeds in the seed-metering device were obtained,concurrently,the stress trend in the grain group was determined as a function of *** simulation results suggest that at larger speeds,the metering index of the seed meter gradually decreases,while the index and the missing index gradually *** the tilt angle increased,the multiples index and missing index gradually decreased,while the multiples index gradually *** the seed meter speed reached 50 r/min and the tilt angle was 15°,the seed meter had a relatively good working performance with a seed spacing acceptance index of 92.59%,a multiples index of 1.85%,and a missing rate index of 5.56%.The seed meter was tested on a bench by using a JPS-12 performance-tester *** the aforementioned speed and angle,the coefficient of variation for the cottonseed spacing was 2.1%.The field trial results indicated that the multiples and the missing rates were higher than those for the tester bench but still met a passing rate of more than 90%.The coefficient of variation for the seed spacing was less than 10%,suggesting that the design could be used for field *** resulting seeding uniformity was higher under these conditions,which indicates that the seed meter has a better working performance and the bench has a good seeding effect.

关键词： spoon-wheel type seeder EDEM simulation tester bench field trial cottonseed