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Journal of Geographical Sciences 2025年第1期35卷 65-87页

作者： CHEN Meng ZHOU Qiuwen PENG Dawei YAN Weihong School of Geography and Environmental Science Guizhou Normal University Huanjiang Observation and research station for Karst Ecosystem Guangxi Key Laboratory of Karst Ecological Processes and Services Institute of Subtropical Agriculture CAS University of Chinese Academy of Sciences Faculty of Geographical Science Beijing Normal University Forestry Bureau of Shibing County

Terrestrial ecosystems heavily depend on vegetation,which responds to carbon dioxide （CO2） fertilization in hot and humid *** subtropical humid karst region is a hot and humid region;whether and to what extent CO2fertilization affects vegetation changes in such regions remains *** this study,we investigated the degree to which CO2fertilization influences vegetation changes,along with their spatial and temporal differences,in the subtropical humid karst region using time-lag effect analysis,a random forest model,and multiple regression *** showed that CO2fertilization plays an important role in vegetation changes,exhibiting clear spatial variations across different geomorphological zones,with its degree of influence ranging mainly between 11%and 25%.The highest contribution of CO2fertilization was observed in the karst basin and non-karstic region,whereas the lowest contribution was found in the karst plateau *** studies have primarily attributed vegetation changes in subtropical humid karst region to ecological engineering,leading to an overestimation of its contribution to these *** findings of this study enhance the understanding of the mechanism of vegetation changes in humid karst region and provide theoretical and practical insights for ecological and environmental protection in these regions.

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An apple rootstock overexpressing a peach CBF gene alters growth and flowering in the scion but does not impact cold hardiness or dormancy

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horticulture research 2016年第1期3卷 287-295页

作者： Timothy S Artlip Michael E Wisniewski Rajeev Arora John L Norelli usda-ars Appalachian Fruit Research StationKearneysvilleWVUSA Department of horticulture Iowa State UniversityAmesIAUSA

The C-repeat binding factor(CBF)transcription factor is involved in responses to low temperature and water deficit in many plant *** of CBF genes leads to enhanced freezing tolerance and growth inhibition in many *** overexpression of a peach CBF(PpCBF1)gene in a transgenic line of own-rooted apple(Malus×domestica)M.26 rootstock(T166)trees was previously reported to have additional effects on the onset of dormancy and time of spring *** the current study,the commercial apple cultivar‘Royal Gala’(RG)was grafted onto either non-transgenic M.26 rootstocks(RG/M.26)or transgenic M.26(T166)rootstocks(RG/T166)and field grown for 3 *** PpCBF1 transcript was detected in the phloem or cambium of RG scions grafted on T166 rootstocks indicating that no graft transmission of transgene mRNA had *** contrast to own-rooted T166 trees,no impact of PpCBF1 overexpression in T166 rootstocks was observed on the onset of dormancy,budbreak or non-acclimated leaf-cold hardiness in RG/T166 ***,however,as measured by stem caliper,current-year shoot extension and overall height,was reduced in RG/T166 trees compared with RG/M.26 *** flowering was evident in both RG/T166 and RG/M.26 trees in the second season,the number of trees in flower,the number of shoots bearing flowers,and the number of flower clusters per shoot was significantly higher in RG/M.26 trees than RG/T166 trees in both the second and third year after *** levels of RGL(DELLA)gene expression were observed in RG/T166 trees and T166 trees,which may play a role in the reduced growth observed in these tree types.A model is presented indicating how CBF overexpression in a rootstock might influence juvenility and flower abundance in a grafted scion.

关键词： impact CBF grafted

Alteration of TAC1 expression in Prunus species leads to pleiotropic shoot phenotypes

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horticulture research 2018年第1期5卷 632-640页

作者： Courtney A.Hollender Jessica M.Waite Amy Tabb Doug Raines Srinivasan Chinnithambi Chris Dardick usda-ars Appalachian Fruit research station KearneysvilleWV25430USA Department of horticulture Michigan State UniversityEast LansingMI48824USA

Prunus persica(peach)trees carrying the“Pillar”or“Broomy”trait(br)have vertically oriented branches caused by loss-of-function mutations in a gene called TILLER ANGLE CONTROL 1(TAC1).TAC1 encodes a protein in the IGT gene family that includes LAZY1 and DEEPER ROOTING 1(DRO1),which regulate lateral branch and root orientations,*** we found that some of the native TAC1 alleles in the hexaploid plum species Prunus domestica,which has a naturally more upright stature,contained a variable length trinucleotide repeat within the same exon 3 region previously found to be disrupted in pillar peach *** silencing of TAC1 in plum resulted in trees with severely vertical branch orientations similar to those in pillar peaches but with an even narrower *** contrast,PpeTAC1 overexpression in plum led to trees with wider branch angles and more horizontal branch *** peach trees and transgenic plum lines exhibited pleiotropic phenotypes,including differences in trunk and branch diameter,stem growth,and twisting branch *** profiling of pillar peach trees revealed differential expression of numerous genes associated with biotic and abiotic stress,hormone responses,plastids,reactive oxygen,secondary,and cell wall ***,the data provide important clues for understanding TAC1 function and show that alteration of TAC1 expression may have broad applicability to agricultural and ornamental tree industries.

关键词： TAC1 branch Prunus

Changes in free amino acids and polyamine levels in Satsuma leaves in response to Asian citrus psyllid infestation and water stress

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Insect Science 2014年第6期21卷 707-716页

作者： Nasir S. A. Malik Jose L. Perez Madhurababu Kunta Joseph M. Patt Robert L. Mangan usda-ars ERRC 600 E Mermaid lane Wyndmoor PA 19038-8598 usda-ars SPARC 2881 F&B Road College Station TX 77845 Texas A&M University-Kingsville Citrus Center 312 North International Blvd Weslaeo TX 78596 U. S. Horticultural research Laboratory 2001 South Rock Road Fort Pierce FL 34945 subtropical Horticultural research station 13601 Old Coulter Road Miami FL 33158 usda-ars 2413 E. Hwy 83 Weslaco TX 78596 USA

The effects of biotic and abiotic stresses on changes in amino acids and polyamine levels in Satsuma orange （Citrus unshiu; cultivar Owari） leaves were inves- tigated. Asian citrus psyllids Diaphorina citri （Kuwayama）（ACP） infestation was used to induce biotic stress while a water deficit was imposed to induce abiotic stress. Potted trees were infested by placing 50 psyllids on 3 citrus leaves enclosed in nylon mesh bags for 5 d. A parallel set of plants were kept water stressed by maintaining the soil at 20% water holding capacity for 5 d. Levels of total free amino acids were higher in water stressed and ACP infested leaves. Polyamine putrescine increased in infested leaves but not in water stressed leaves. Proline was the most abundant amino acid and its levels significantly increased by both biotic and abiotic stresses. Proline levels in infested leaves were significantly higher than the water stressed leaves. Histidine, methionine, asparagine, arginine, serine, and leucine levels also increased significantly in infested leaves, but in water stressed leaves only leucine, methionine, and threonine increased. Levels of amino acids, such as tyrosine, isoleucine, phenylalanine, glutamic acid, and alanine, declined in infested leaves. Under water stress asparagine, phenylalanine, serine, and histidine also declined compared to controls. This indicates that while proteolysis occurred under both stresses, metabolic conversion of amino acids was different under the two stresses. In ACP infested leaves some amino acids may be used as feeding material and/or converted into secondary metabolites for defense.

关键词： amino acids citrus Diaphorina citri polyamines

Effects of Land Cover on Soil Organic Carbon Stock in a Karst Landscape with Discontinuous Soil Distribution

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Journal of Mountain Science 2014年第3期11卷 774-781页

作者： CHEN Xiang-bi ZHENG Hua ZHANG Wei HE Xun-yang LI Lei WU Jin-shui HUANG Dao-you SU Yi-rong Key Laboratory of Agro-ecological Processes in subtropical Region Institute of Subtropical Agriculture Chinese Academy of Sciences Huanjiang Observation and research station for Karst Eco-systems Guangxi Institute of subtropical Crops

Land cover type is critical for soil organic carbon （SOC） stocks in territorial ecosystems. However, impacts of land cover on SOC stocks in a karst landscape are not fully understood due to discontinuous soil distribution. In this study, considering soil distribution, SOC content and density were investigated along positive successional stages （cropland, plantation, grassland, scrubland, secondary forest, and primary forest） to determine the effects of land cover type on SOC stocks in a subtropical karst area. The proportion of continuous soil on the ground surface under different land cover types ranged between 0.0% and 79.8%. As land cover types changed across the positive successional stages, SOC content in both the 0-20 cm and 20-50 cm soil layers increased significantly. SOC density （SOCD） within O-lOO cm soil depth ranged from 1.45 to 8.72 kg m^-2, and increased from secondary forest to primary forest, plantation, grassland, scrubland, and cropland, due to discontinuous soil distribution. Discontinuous soil distribution had a negative effect on 8OC stocks, highlighting the necessity for accurate determination of soil distribution in karst areas. Generally, ecological restoration had positive impacts on SOC accumulation in karst areas, but this is a slow process. In the short term, the conversion of croplandto grassland was found to be the most efficient way for SOC sequestration.

关键词： Soil organic carbon (SOC) Karst area Discontinuous soil distribution Land cover type Carbon sequestration potential

Nitrous Oxide Emissions from a Masson Pine Forest Soil in subtropical Central China

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Pedosphere 2015年第2期25卷 263-274页

作者： CHEN Dan FU Xiao-Qing WANG Cong LIU Xin-Liang LI Hang SHEN Jian-Lin WANG Yi LI Yong WU Jin-Shui Changsha research station for Agricultural and Environmental Monitoring Key Laboratory of Agro-ecological Processes in Subtropical RegionInstitute of Subtropical AgricultureChinese Academy of Sciences

The forest ecosystem plays a pivotal role in contributing greenhouse gases to the *** order to characterize the temporal pattern of nitrous oxide(N_2O) emissions and identify the key factors affecting N_2O emissions from a Masson pine forest in a hilly red-soil region in subtropical central China,we measured the N_2O emissions in Jinjing of Hunan Province using the static chambergas chromatographic method for 3 years(2010-2012) and analyzed the relationships between the N_2O fluxes and the environmental *** results revealed that the N_2O fluxes over the 3 years varied from-36.0 to 296.7 μg N m^(-2) h^(-1),averaging 18.4±5.6 μg N m^(-2) h^(-1)(n=3).The average annual N_2O emissions were estimated to be 1.6±0.3 kg N ha^(-1) year^(-1).The N_2O fluxes exhibited clear intra-annual(seasonal) variations as they were higher in summers and lower in *** with other forest observations in the subtropics,N_2O emissions at our site were relatively high,possibly due to the high local dry/wet N deposition,and were mostly sensitive to variations in precipitation and soil ammonium N *** this work,a multiple linear regression model was developed to determine the influence of environmental factors on N_2O emissions,in which a category predictor of "Season" was intentionally used to account for the seasonal variation of the N_2O *** a model explained almost 40%of the total variation in daily N_2O emissions from the Masson pine forest soil studied(P<0.001).

关键词： environmental factors multiple linear regression model N deposition season subtropical forests

Contribution of atmospheric nitrogen deposition to diffuse pollution in a typical hilly red soil catchment in southern China

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Journal of Environmental Sciences 2014年第9期26卷 1797-1805页

作者： Jianlin Shen Jieyun Liu Yong Li Yuyuan Li Yi Wang Xuejun Liu Jinshui Wu Changsha research station for Agricultural & Environment Observation Institute of Subtropical AgricultureChinese Academy of Sciences Key Laboratory of Agro-Ecological Processes in subtropical Regions Institute of Subtropical AgricultureChinese Academy of Sciences College of Resources and Environmental Sciences China Agricultural University

Atmospheric nitrogen （hi） deposition is currently high and meanwhile diffuse N pollution is also serious in China. The correlation between N deposition and riverine N export and the contribution of N deposition to riverine N export were investigated in a typical hilly red soil catchment in southern China over a two-year period. N deposition was as high as 26.1 to 55.8 kg N/（ha-yr） across different land uses in the studied catchment, while the riverine N exports ranged from 7.2 to 9.6 kg N/（ha-yr） in the forest sub-catchment and 27.4 to 30.3 kg N/（***） in the agricultural sub-catchment. The correlations between both wet N deposition and riverine N export and precipitation were highly positive, and so were the correlations between NH-N or NO2-N wet deposition and riverine NH4-N or NO3-N exports except for NH-N in the agricultural sub-catchment, indicating that N deposition contributed to riverine N export. The monthly export coefficients of atmospheric deposited N from land to river in the forest sub-catchment （with a mean of 14%） presented a significant positive correlation With precipitation, while the monthly contributions of atmospheric deposition to riverine N export （with a mean of 18.7% in the agricultural sub-catchment and a mean of 21.0% in the whole catchment） were significantly and negatively correlated with precipitation. The relatively high contribution of N deposition to diffuse N pollution in the catchment suggests that efforts should be done to control anthropogenic reactive N emissions to the atmosphere in hilly red soil regions in southern China.

关键词： Nitrogen depositionWet depositionDry depositionRiverine nitrogen exportNon-point source pollution

Differential Responses of Nitrifier and Denitrifier to Dicyandiamide in Short- and Long-Term Intensive Vegetable Cultivation Soils

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Journal of Integrative Agriculture 2014年第5期13卷 1090-1098页

作者： LIU Yi YANG Yang QIN Hong-ling ZHU Yi-jun WEI Wen-xue Key Laboratory of Agro-Ecological Processes in subtropical Regions and Taoyuan station of Agro-Ecology research Institute of Subtropical Agriculture Chinese Academy of Sciences Tianjin Land & Resources & Housing Management research Centre

Nitrification inhibitors, such as dicyandiamide （DCD）, have been shown to decrease leaching from urea- and ammoniumbased fertilizers in agricultural soils. The effect of nitrification inhibitors on nitrifier and denitrifier in short- and long-term intensive vegetable cultivation soils was poorly understood. In this study, the pot trial was conducted to investigate the differential responses of nitrifier （amoA-containing bacteria） and denitrifier （nirK-containing bacteria） to DCD in short-（soil S） and long-term （soil L） intensive vegetable cultivation soils. Quantitative polymerase chain reaction （qPCR） and terminal restriction fragment length polymorphism （T-RFLP） were employed to detect the abundance and composition of amoA- and nirK-containing communities. The results indicated that application of DCD led to a consistently higher NH4＋-N concentration during the whole incubation in soil L, while it was quickly decreased in soil S after 21 days. Furthermore, DCD induced more severe decrease of the abundance of amoA-containing bacteria in soil L than in soil S. However, the abundance of the nirK- containing community was not significantly affected by DCD in both soils. Long-term vegetable cultivation resulted in a super-dominant amoA-containing bacteria group and less divergence in soil L compared with soil S, and DCD did not cause obvious shifts of the composition of ammonia-oxidising bacteria （AOB）. On the contrary, both amoA- and nirK-containing bacterial compositions were influenced by DCD in soil S. The results suggested that long-term intensive vegetable cultivation with heavy nitrogen fertilization resulted in significant shifts of AOB community, and this community was sensitive to DCD, but denitrifiers were not clearly affected by DCD.

关键词： DCD amoA nirK vegetable soil

Modified Method for Estimating Organic Carbon Density in Discontinuous Karst Soil Using Ground-Penetrating Radar and Geostatistics

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Journal of Mountain Science 2015年第5期12卷 1229-1240页

作者： LI Lei XIA Yin-hang LIU Shu-juan ZHANG Wei CHEN Xiang-bi ZHENG Hua QIU Hu-sen HE Xun-yang SU Yi-rong Key Laboratory of Agro-ecological Processes in subtropical Region Institute of Subtropical Agriculture Chinese Academy of Sciences Huanjiang Observation and research station for Karst Eco-systems University of Chinese Academy of sciences Guangxi Institute of subtropical Crops

The conventional method which assumes the soil distribution is continuous was unsuitable for estimating soil organic carbon density(SOCD) in Karst areas because of its discontinuous soil distribution. The accurate estimation of SOCD in Karst areas is essential for carbon sequestration assessment in China. In this study, a modified method,which considers the vertical proportion of soil area in the profile when calculating the SOCD, was developed to estimate the SOCD in a typical Karst peak-cluster depression area in southwest China. In the modified method, ground-penetrating radar(GPR) technology was used to detect the distribution and thickness of soil. The accuracy of the method was confirmed through comparison with the data obtained using a validation method, in which the soil thickness was measured by excavation. In comparison with the conventional method and average-soil-depth method,the SOCD estimated using the GPR method showed the minimum relative error with respect to that obtained using the validation method. At a regional scale, the average SOCDs at depths of 0-20 cm and 0-100 cm, which were interpolated by ordinary kriging,were 1.49(ranging from 0.03-5.65) and 2.26(0.09-11.60) kgm-2based on GPR method in our study area(covering 393.6 hm2), respectively. Therefore, the modified method can be applied on the accurate estimation of SOCD in discontinuous soil areas such as Karst regions.

关键词： Discontinuous soil Organic carbondensity Soil distribution Estimation method Ground penetrating radar Karst Peak clusterdepression

Promoter insertion leads to polyembryony in mango-a case of convergent evolution with citrus

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horticulture research 2023年第12期10卷 165-174页

作者： Chandra Bhan Yadav Ada Rozen Ravit Eshed Mazal Ish-Shalom Adi Faigenboim Natalie Dillon Ian Bally Matthew Webb David Kuhn Ron Ophir Yuval Cohen Amir Sherman Institute of Plant Sciences Volcani Research CenterDerech Hamacabim 68Rishon LeZionP.O.Box 151597528809Israel Department of Genetics Genomicsand BreedingNIAB-EMREast MallingME196BJUnited Kingdom Department of Agriculture and Fisheries Horticulture and Forestry Science28 Peters StMareebaQLD 4880Australia Department of Agriculture and Fisheries Horticulture and Forestry ScienceEcosciences Precinct41 Boggo RoadDutton ParkBrisbaneQLD 4001Australia subtropical horticulture research station USDA-ARS13601 Old Cutler RdCoral GablesFL 33158United States

Sexual reproduction in plants is the main pathway for creating new genetic combinations in modern *** heterozygous plants,after the identification of a plant with desired traits,vegetative propagation(cloning)is the primary path to create genetically uniform *** natural plant mechanism that creates genetically uniform plants(clones)is *** fruit crops like citrus and mango,sporophytic apomixis results in polyembryony,where seeds contain multiple embryos,one of which is sexually originated and the others are vegetative clones of the parent mother *** the mango genome and genetic analysis of a diverse germplasm collection,we identified MiRWP as the gene that causes polyembryony in *** is a strong correlation between a specific insertion in the gene’s promoter region and altered expression in flowers and developing fruitlets,inducing multiple *** MiRWP gene is an ortholog of CitRWP that causes polyembryony in *** on the data,we speculate that promoter insertion events,which occurred independently in citrus and mango,induced nucellar *** results suggest convergent evolution of polyembryony in the two *** work is required to demonstrate the utility of these genes(mango and citrus)in other biological systems as a tool for the clonal production of other crops.

关键词： citrus crops insertion