Background In the current context of global warming,thermal manipulation of avian embryos has received increasing attention as a strategy to promote heat tolerance in avian species by simply increasing the egg incubat...Background In the current context of global warming,thermal manipulation of avian embryos has received increasing attention as a strategy to promote heat tolerance in avian species by simply increasing the egg incubation temperature.However,because of their likely epigenetic origin,thermal manipulation effects may last more than one generation with consequences for the poultry industry.In this work,a multigenerational and transgenerational analysis of thermal manipulation during embryogenesis was performed to uncover the long-term effects of such procedure.Results Thermal manipulation repeated during 4 generations had an effect on hatchability,body weight,and weight of eggs laid in Japanese quails,with some effects increasing in importance over generations.Moreover,the effects on body weight and egg weight could be transmitted transgenerationally,suggesting non-genetic inheritance mechanisms.This hypothesis is reinforced by the observed reversion of the effect on growth after five unexposed generations.Interestingly,a beneficial effect of thermal manipulation on heat tolerance was observed a few days after hatching,but this effect was not transgenerational.Conclusions Our multigenerational study showed that thermal conditioning of quail embryos has a beneficial effect on post-hatch heat tolerance hampered by transgenerational but reversible defects on growth.Assuming that no genetic variability underlies these changes,this study provides the first demonstration of epigenetic inheritance of traits induced by environmental temperature modification associated with long-term impacts in an avian species.展开更多
This study aims at evaluating the potential suitability of Tetouan and Meknes (central Morocco) clay material as raw materials in various ceramic applications by investigating their textural, chemical, thermal and fir...This study aims at evaluating the potential suitability of Tetouan and Meknes (central Morocco) clay material as raw materials in various ceramic applications by investigating their textural, chemical, thermal and firing characteristics. Textural properties were identified by specific surface area, cation exchange capacity (CEC) and bulk density (ρs). Chemical and thermal properties were assessed using XRF and TG/DTA techniques, respectively. Firing characteristics at temperatures from 800℃ to 1100℃ were determined by linear firing shrinkage, loss on weight and water absorption capacity. The Meknes clays are characterised by medium cation exchange capacity (CEC) and specific surface area (SSA) values due to their moderate smectite content. The Tetouan clays have medium to low CEC and medium SSA values. The main oxides in the clayey samples are SiO2 (35 - 54.3 wt%), Al2O3 (20.6 - 43.9 wt%), and Fe2O3 (9.7 - 22.4 wt%). The amount of CaO in Meknes clays ranges from 8 to 12 wt%, whereas CaO is only present in some Tetouan clay (TE4, TE7, TN4 and TN5). A significant densification of ceramic behaviour could be noticed for most of Tetouan clays at firing temperatures above 1000℃. Meknes clays show earlier densification from 800℃. The chemical, textural and ceramic properties of Tetouan and Meknes clays indicate their suitability as raw materials for the production of structural ceramics. The high amount of Fe2O3 in all clays makes them inappropriate in fine ceramics.展开更多
Maintaining a land base that supports safe and realistic training operations is a significant challenge for military land managers which can be informed by frequent monitoring of land condition in relation to manageme...Maintaining a land base that supports safe and realistic training operations is a significant challenge for military land managers which can be informed by frequent monitoring of land condition in relation to management practices. This study explores the relationship between fire and trends in tallgrass prairie vegetation at military and non-military sites in the Kansas Flint Hills. The response variable was the long-term linear trend (2001-2010) of surface greenness measured by MODIS NDVI using BFAST time series trend analysis. Explanatory variables included fire regime (frequency and seasonality) and spatial strata based on existing management unit boundaries. Several non-spatial generalized linear models (GLM) were computed to explain trends by fire regime and/or stratification. Spatialized versions of the GLMs were also constructed. For non-spatial models at the military site, fire regime explained little (4%) of the observed surface greenness trend compared to strata alone (7% - 26%). The non-spatial and spatial models for the non-military site performed better for each explanatory variable and combination tested with fire regime. Existing stratifications contained much of the spatial structure in model residuals. Fire had only a marginal effect on surface greenness trends at the military site despite the use of burning as a grassland management tool. Interestingly, fire explained more of the trend at the non-military site and models including strata improved explanatory power. Analysis of spatial model predictors based on management unit stratification suggested ways to reduce the number of strata while achieving similar performance and may benefit managers of other public areas lacking sound data regarding land usage.展开更多
Background: While agriculture has taken much environmental water in Australia's Murray-Darling Basin, agricultural expansion has resulted in a vast number of farm dams, almost three-quarters of a million in the Mu...Background: While agriculture has taken much environmental water in Australia's Murray-Darling Basin, agricultural expansion has resulted in a vast number of farm dams, almost three-quarters of a million in the Murray-Darling Basin alone.Methods: Over a summer we studied(1) waterbird abundance and species richness and(2) the influence of biophysical and landscape characteristics across 49 farm dams at a large mixed-enterprise farm in northern Victoria on the southern reach of the Murray-Darling Basin.Results: On average, dams were found to host 27.1 ± 71.1 individuals/ha and 1.8 ± 2.9 species per pond. Such densities are comparable to those on natural wetlands. Dam surface area and perimeter and amount of vegetation were positively and strongly correlated with the Rallidae density(birds/ha), but no other parameters were strongly correlated with any other functional group. The landscape in which the dams were embedded had a highly significant effect(p < 0.001) on the number of birds found on a dam.Conclusions: Our research needs to be complemented with further studies in other parts of the Basin and on other taxa, but given at our site they supported similar densities of individuals and species to natural wetlands, and given the fact that there are 710,539 farm dams in the Murray-Darling Basin, which hosts much of Australia's waterbird fauna, it is reasonable to suggest that farm dams are overlooked, and possibly very important, avian biodiversity hotspots. It also highlights the importance of a landscape setting, in which dams are situated, on the number of birds using the dams.展开更多
Coffee plays a key role in the generation of rural employment in Colombia.More than 785,000 workers are directly employed in this activity,which represents the 26%of all jobs in the agricultural sector.Colombian coffe...Coffee plays a key role in the generation of rural employment in Colombia.More than 785,000 workers are directly employed in this activity,which represents the 26%of all jobs in the agricultural sector.Colombian coffee growers estimate the production of cherry coffee with the main aim of planning the required activities,and resources(number of workers,required infrastructures),anticipating negotiations,estimating,price,and foreseeing losses of coffee production in a specific territory.These important processes can be affected by several factors that are not easy to predict(e.g.,weather variability,diseases,or plagues.).In this paper,we propose a non-destructive time series model,based on weather and crop management information,that estimate coffee production allowing coffee growers to improve their management of agricultural activities such as flowering calendars,harvesting seasons,definition of irrigation methods,nutrition calendars,and programming the times of concentration of production to define the amount of personnel needed for harvesting.The combination of time series and machine learning algorithms based on regression trees(XGBOOST,TR and RF)provides very positive results for the test dataset collected in real conditions for more than a year.The best results were obtained by the XGBOOST model(MAE=0.03;RMSE=0.01),and a difference of approximately 0.57%absolute to the main harvest of 2018.展开更多
Farm management practices differ considerably among farmers. In this article, we explore the processes which farmers go through when making operational decisions about technical interventions. Because farmers have dif...Farm management practices differ considerably among farmers. In this article, we explore the processes which farmers go through when making operational decisions about technical interventions. Because farmers have different approaches to the decision-making process, it is essential to describe these differences to identify areas in which management skills require improvement. This study identifies and represents contextual, informational and inferential aspects of the cognitive work a farm manager performs in operational decision-making. We developed a conceptual modelling framework that structures the decision-making behaviour along a set of cognitive processes such as perception, interpretation, goal reasoning, planning and judgment. These processes are activated repeatedly throughout the production process. The framework can help characterize variation in management behaviour and performance, and identify promising directions for improvement.展开更多
The purpose of this contribution is to lay down a preparatory groundwork for an ontology of ecosystem services in the setting of agroecosystems viewed as social-ecological systems. This ontology aims at defining a set...The purpose of this contribution is to lay down a preparatory groundwork for an ontology of ecosystem services in the setting of agroecosystems viewed as social-ecological systems. This ontology aims at defining a set of representational primitives with which to model agroecosystems, through the prism of ecosystem service flows to and from agriculture. It helps delineate between biophysical structures, processes, functions, and ecosystem services. On the human side of agroecosystems, the ontology includes a conceptualization of the behaviors that govern the management of ecosystem services at different levels. It strengthens the existing analytic basis of multidisciplinary research on ecosystem services in agroecosystems by prompting modelers to stick to a homogeneous dynamic-system decomposition of the target agroecosystem. Most importantly, it provides the conceptual link between biophysical research on ecosystem services and equally important considerations on cognitive and social aspects involved in agricultural and landscape-level decisions that aim at implementing agroecological principles.展开更多
Members of the ERF Family of Transcription Factors play an important role in plant development and gene expression that regulates responses to biotic and abiotic stress.This work identified 36 ERF family genes in Coff...Members of the ERF Family of Transcription Factors play an important role in plant development and gene expression that regulates responses to biotic and abiotic stress.This work identified 36 ERF family genes in Coffea arabica within the AP2/ERF full domain,using the EST-based genomic resource of the Brazilian Coffee Genome Project.The ERF family genes were classified into nine of the ten existing groups through phylogenetic analysis of the deduced amino acid sequences and comparison with the sequences of the ERF family genes in Arabidopsis.In addition to the AP2 domain,other conserved domains were identified,typical of members of each group.The in silico analysis and expression profiling showed high levels of expression for libraries derived from tissues of fruits,leaves and flowers as well as for libraries subjected to water stress.These results suggest the participation of the ERF family genes of C.arabica in distinct biological functions,such as control of development,maturation,and responses to water stress.The results of this work imply in the selection of promising genes for further functional characterizations that will provide a better understanding of the complex regulatory networks related to plant development and responses to stress,opening up opportunities for coffee breeding programs.展开更多
The Soil and Water Assessment Tool(SWAT)model was used to assess the impacts of different land use scenarios on hydrological processes in the Fuhe watershed in Poyang Lake Basin,East China.A total of 12 model paramete...The Soil and Water Assessment Tool(SWAT)model was used to assess the impacts of different land use scenarios on hydrological processes in the Fuhe watershed in Poyang Lake Basin,East China.A total of 12 model parameters were calibrated with observed monthly runoff data for 1982-1988 and validated for 1991-1998 for baseline conditions.The baseline test results of R2 and Nash-Sutcliffe model efficiency(NSE)values ranged between 0.88 and 0.94 across the calibration and validation periods,indicating that SWAT accurately replicated the Fuhe watershed streamflow.Several different land use scenarios were then simulated with the model,focusing on the impacts of land use change on the hydrology of the watershed.The results of hypothetical scenario simulations revealed that surface runoff declined while groundwater recharge and evapotranspiration(ET)increased,as forest land,agriculture land and/or grassland areas increased,as well as when paddy field and urban areas decreased.These results further showed that forest land has a higher capacity to conserve the water as compared to pasture land.The results of the real scenario simulations revealed that urbanization is the strongest contributor to changes in surface runoff,water yield,and ET.Urbanization can be considered as a potential major environmental stressor controlling hydrological components.展开更多
Symbiotic relationships between fungal endophytes and grass species are known to increase stress resistance in the grass host;however,there is little evidence to suggest that the positive effects occur early in the gr...Symbiotic relationships between fungal endophytes and grass species are known to increase stress resistance in the grass host;however,there is little evidence to suggest that the positive effects occur early in the grass life cycle.In this study,we explored the effects of the endophyte Epichloe¨festucae on the growth and survival of Festuca eskia seedlings under drought and frequent cutting stress.Methods Festuca eskia seedlings were collected from the western part of the plant repartition area in a non-symbiotic population located in a mesic and heavily grazed site(W-NS)and from the eastern part in a symbiotic population from a xeric and lightly grazed site(E-S).The E-S population was experimentally freed from its endophyte(E-F).Two greenhouse experiments were conducted to compare growth and survival between the three seedling types under drought stress and frequent cutting.In the first experiment,126 seedlings per seedling type(n=378)were grown for 6 weeks under non-limiting conditions before the cessation of watering.After 3 weeks without irrigation,full irrigation was restored for 10 days to measure the survival rate.Leaf length,leaf elongation rate and survival rate were assessed per population.In the second experiment,156 seedlings per seedling type(n=468)were grown under non-limiting conditions.All seedlings were cut to 3 cmhigh,twice a week,during the first month of growth.Leaf elongation and tillering were monitored on 52 seedlings per seedling type.For each type,seedling survival rate was determined by the number of plants alive after 10 days of regrowth,without cutting.Important Findings The drought experiment revealed a phenotypic differentiation to drought in 30 F.eskia populations,suggesting adaptive differentiation:the eastern seedlings showed the highest survival rate.A tradeoff between growth and survival was highlighted:the highest drought survival rate was associated with the lowest leaf elongation rate under non-limiting water conditions.Endophyte presence in the eastern population increased seedling drought survival.In contrast,cutting survival rate was similar between W-NS and E-S because the presence of the endophyte increased seedling survival to frequent cutting.However,this positive effect came with a cost:the endophyte reduced seedling tillering rate.展开更多
Malformed fruits depreciate a plant’s market value.In tomato(Solanum lycopersicum),fruit malformation is associated with the multi-locule trait,which involves genes regulating shoot apical meristem(SAM)development.Th...Malformed fruits depreciate a plant’s market value.In tomato(Solanum lycopersicum),fruit malformation is associated with the multi-locule trait,which involves genes regulating shoot apical meristem(SAM)development.The expression pattern of TOPLESS3(SITPL3)throughout SAM development prompted us to investigate its functional significance via RNA interference(RNAi)and clustered regularly interspaced short palindromic repeats/CRISPR-associated nuclease 9(Cas9)-mediated gene editing.Lower SITPL3 transcript levels resulted in larger fruits with more locules and larger SAMs at the 5 d after germination(DAG5)stage.Differentially expressed genes in the SAM of wild-type(WT)and SITPL3-RNAi plants,identified by transcriptome deep sequencing(RNA-seq),were enriched in the gibberellin(GA)biosynthesis and plant hormone signaling pathways.Moreover,exogenous auxin and paclobutrazol treatments rescued the multi-locule phenotype,indicating that SITPL3 affects SAM size by mediating auxin and GA levels in the SAM.Furthermore,SITPL3 interacted with WUSCHEL(SIWUS),which plays an important role in SAM size maintenance.We conducted RNA-seq and DNA affinity purification followed by sequencing(DAP-seq)analyses to identify the genes regulated by SITPL3 and SIWUS in the SAM and to determine how they regulate SAM size.We detected24 overlapping genes regulated by SITPL3 and SIWUS and harboring an SIWUS-binding motif in their promoters.Furthermore,functional annotation revealed a notable enrichment for functions in auxin transport,auxin signal transduction,and GA biosynthesis.Dual-luciferase assays also revealed that SITPL3 enhances SIWUS-mediated regulation(repression and activation)of SIPIN3 and SIGA2 ox4 transcription,indicating that the SITPL3-SIWUS module regulates SAM size by mediating auxin distribution and GA levels,and perturbations of this module result in enlarged SAM.These results provide novel insights into the molecular mechanism of SAM maintenance and locule formation in tomato and highlight the SITPL3-SIWUS module as a key regulator.展开更多
Dear Editor Strigolactones (SLs) are novel phytohormones that shape plant architecture by inhibiting shoot branching and regulating root growth, besides their established functions in stimulating seed germination of...Dear Editor Strigolactones (SLs) are novel phytohormones that shape plant architecture by inhibiting shoot branching and regulating root growth, besides their established functions in stimulating seed germination of root-parasitic weeds, such as Striga and Phelipanche species, and inducing hyphal branching in arbuscular mycorrhizal (AM) fungi (AI-Babili and Bouwmeester, 2015). Canonical SLs are divided into strigoland orobanchollike subfamilies with a typical structure consisting of a tricyclic (ABC-ring) and a monocyclic lactone (D-ring), which are connected by an enol ether bridge (Figure 1A and Supplemental Figure 1). SLs are synthesized from carotenoids via carlactone, which lacks the B/C-ring (Alder et al., 2012). In Arabidopsis, carlactone (Figure 1A) is converted by MAX1, a member of the CYP711 family, into carlactonoic acid, after methylation, which, can bind to SL receptor (Abe et al., 2014). In rice, a MAX1 homolog, the carlactone oxidase, introduces B/C-rings into carlactone,展开更多
Plant root-nodule symbiosis(RNS)with mutualistic nitrogen-fixing bacteria is restricted to a single clade of angiosperms,the Nitrogen-Fixing Nodulation Clade(NFNC),and is best understood in the legume family.Nodulatin...Plant root-nodule symbiosis(RNS)with mutualistic nitrogen-fixing bacteria is restricted to a single clade of angiosperms,the Nitrogen-Fixing Nodulation Clade(NFNC),and is best understood in the legume family.Nodulating species share many commonalities,explained either by divergence from a common ancestor over 100 million years ago or by convergence following independent origins over that same time period.Regardless,comparative analyses of diverse nodulation syndromes can provide insights into constraints on nodulation—what must be acquired or cannot be lost for a functional symbiosis—and the latitude for Plant Communications Genomic landscape of nodulation variation in the symbiosis.However,much remains to be learned about nodulation,especially outside of legumes.Here,we employed a large-scale phylogenomic analysis across 88 species,complemented by 151 RNA-seq libraries,to elucidate the evolution of RNS.Our phylogenomic analyses further emphasize the uniqueness of the transcription factor NIN as a master regulator of nodulation and identify key muta-tions that affect its function across the NFNC.Comparative transcriptomic assessment revealed nodule-specific upregulated genes across diverse nodulating plants,while also identifying nodule-specific and nitrogen-response genes.Approximately 70%of symbiosis-related genes are highly conserved in the four representative species,whereas defense-related and host-range restriction genes tend to be lineage specific.Our study also identified over 900000 conserved non-coding elements(CNEs),over 300000 of which are unique to sampled NFNC species.NFNC-specific CNEs are enriched with the active H3K9ac mark and are correlated with accessible chromatin regions,thus representing a pool of candidate regula-tory elements for genes involved in RNS.Collectively,our results provide novel insights into the evolution of nodulation and lay a foundation for engineering of RNS traits in agriculturally important crops.展开更多
文摘Background In the current context of global warming,thermal manipulation of avian embryos has received increasing attention as a strategy to promote heat tolerance in avian species by simply increasing the egg incubation temperature.However,because of their likely epigenetic origin,thermal manipulation effects may last more than one generation with consequences for the poultry industry.In this work,a multigenerational and transgenerational analysis of thermal manipulation during embryogenesis was performed to uncover the long-term effects of such procedure.Results Thermal manipulation repeated during 4 generations had an effect on hatchability,body weight,and weight of eggs laid in Japanese quails,with some effects increasing in importance over generations.Moreover,the effects on body weight and egg weight could be transmitted transgenerationally,suggesting non-genetic inheritance mechanisms.This hypothesis is reinforced by the observed reversion of the effect on growth after five unexposed generations.Interestingly,a beneficial effect of thermal manipulation on heat tolerance was observed a few days after hatching,but this effect was not transgenerational.Conclusions Our multigenerational study showed that thermal conditioning of quail embryos has a beneficial effect on post-hatch heat tolerance hampered by transgenerational but reversible defects on growth.Assuming that no genetic variability underlies these changes,this study provides the first demonstration of epigenetic inheritance of traits induced by environmental temperature modification associated with long-term impacts in an avian species.
文摘This study aims at evaluating the potential suitability of Tetouan and Meknes (central Morocco) clay material as raw materials in various ceramic applications by investigating their textural, chemical, thermal and firing characteristics. Textural properties were identified by specific surface area, cation exchange capacity (CEC) and bulk density (ρs). Chemical and thermal properties were assessed using XRF and TG/DTA techniques, respectively. Firing characteristics at temperatures from 800℃ to 1100℃ were determined by linear firing shrinkage, loss on weight and water absorption capacity. The Meknes clays are characterised by medium cation exchange capacity (CEC) and specific surface area (SSA) values due to their moderate smectite content. The Tetouan clays have medium to low CEC and medium SSA values. The main oxides in the clayey samples are SiO2 (35 - 54.3 wt%), Al2O3 (20.6 - 43.9 wt%), and Fe2O3 (9.7 - 22.4 wt%). The amount of CaO in Meknes clays ranges from 8 to 12 wt%, whereas CaO is only present in some Tetouan clay (TE4, TE7, TN4 and TN5). A significant densification of ceramic behaviour could be noticed for most of Tetouan clays at firing temperatures above 1000℃. Meknes clays show earlier densification from 800℃. The chemical, textural and ceramic properties of Tetouan and Meknes clays indicate their suitability as raw materials for the production of structural ceramics. The high amount of Fe2O3 in all clays makes them inappropriate in fine ceramics.
文摘Maintaining a land base that supports safe and realistic training operations is a significant challenge for military land managers which can be informed by frequent monitoring of land condition in relation to management practices. This study explores the relationship between fire and trends in tallgrass prairie vegetation at military and non-military sites in the Kansas Flint Hills. The response variable was the long-term linear trend (2001-2010) of surface greenness measured by MODIS NDVI using BFAST time series trend analysis. Explanatory variables included fire regime (frequency and seasonality) and spatial strata based on existing management unit boundaries. Several non-spatial generalized linear models (GLM) were computed to explain trends by fire regime and/or stratification. Spatialized versions of the GLMs were also constructed. For non-spatial models at the military site, fire regime explained little (4%) of the observed surface greenness trend compared to strata alone (7% - 26%). The non-spatial and spatial models for the non-military site performed better for each explanatory variable and combination tested with fire regime. Existing stratifications contained much of the spatial structure in model residuals. Fire had only a marginal effect on surface greenness trends at the military site despite the use of burning as a grassland management tool. Interestingly, fire explained more of the trend at the non-military site and models including strata improved explanatory power. Analysis of spatial model predictors based on management unit stratification suggested ways to reduce the number of strata while achieving similar performance and may benefit managers of other public areas lacking sound data regarding land usage.
文摘Background: While agriculture has taken much environmental water in Australia's Murray-Darling Basin, agricultural expansion has resulted in a vast number of farm dams, almost three-quarters of a million in the Murray-Darling Basin alone.Methods: Over a summer we studied(1) waterbird abundance and species richness and(2) the influence of biophysical and landscape characteristics across 49 farm dams at a large mixed-enterprise farm in northern Victoria on the southern reach of the Murray-Darling Basin.Results: On average, dams were found to host 27.1 ± 71.1 individuals/ha and 1.8 ± 2.9 species per pond. Such densities are comparable to those on natural wetlands. Dam surface area and perimeter and amount of vegetation were positively and strongly correlated with the Rallidae density(birds/ha), but no other parameters were strongly correlated with any other functional group. The landscape in which the dams were embedded had a highly significant effect(p < 0.001) on the number of birds found on a dam.Conclusions: Our research needs to be complemented with further studies in other parts of the Basin and on other taxa, but given at our site they supported similar densities of individuals and species to natural wetlands, and given the fact that there are 710,539 farm dams in the Murray-Darling Basin, which hosts much of Australia's waterbird fauna, it is reasonable to suggest that farm dams are overlooked, and possibly very important, avian biodiversity hotspots. It also highlights the importance of a landscape setting, in which dams are situated, on the number of birds using the dams.
基金We thank to the Telematics Engineering Group(GIT)of the University of Cauca and Tecnicaféfor the technical support.In addition,we are grateful to COLCIENCIAS for PhD scholarship granted to PhD.David Camilo Corrales.This work has been also supported by Innovacción-Cauca(SGR-Colombia)under project“Alternativas Innovadoras de Agricultura Inteligente para sistemas productivos agrícolas del departamento del Cauca soportado en entornos de IoT ID 4633-Convocatoria 04C-2018 Banco de Proyectos Conjuntos UEES-Sostenibilidad”.
文摘Coffee plays a key role in the generation of rural employment in Colombia.More than 785,000 workers are directly employed in this activity,which represents the 26%of all jobs in the agricultural sector.Colombian coffee growers estimate the production of cherry coffee with the main aim of planning the required activities,and resources(number of workers,required infrastructures),anticipating negotiations,estimating,price,and foreseeing losses of coffee production in a specific territory.These important processes can be affected by several factors that are not easy to predict(e.g.,weather variability,diseases,or plagues.).In this paper,we propose a non-destructive time series model,based on weather and crop management information,that estimate coffee production allowing coffee growers to improve their management of agricultural activities such as flowering calendars,harvesting seasons,definition of irrigation methods,nutrition calendars,and programming the times of concentration of production to define the amount of personnel needed for harvesting.The combination of time series and machine learning algorithms based on regression trees(XGBOOST,TR and RF)provides very positive results for the test dataset collected in real conditions for more than a year.The best results were obtained by the XGBOOST model(MAE=0.03;RMSE=0.01),and a difference of approximately 0.57%absolute to the main harvest of 2018.
文摘Farm management practices differ considerably among farmers. In this article, we explore the processes which farmers go through when making operational decisions about technical interventions. Because farmers have different approaches to the decision-making process, it is essential to describe these differences to identify areas in which management skills require improvement. This study identifies and represents contextual, informational and inferential aspects of the cognitive work a farm manager performs in operational decision-making. We developed a conceptual modelling framework that structures the decision-making behaviour along a set of cognitive processes such as perception, interpretation, goal reasoning, planning and judgment. These processes are activated repeatedly throughout the production process. The framework can help characterize variation in management behaviour and performance, and identify promising directions for improvement.
文摘The purpose of this contribution is to lay down a preparatory groundwork for an ontology of ecosystem services in the setting of agroecosystems viewed as social-ecological systems. This ontology aims at defining a set of representational primitives with which to model agroecosystems, through the prism of ecosystem service flows to and from agriculture. It helps delineate between biophysical structures, processes, functions, and ecosystem services. On the human side of agroecosystems, the ontology includes a conceptualization of the behaviors that govern the management of ecosystem services at different levels. It strengthens the existing analytic basis of multidisciplinary research on ecosystem services in agroecosystems by prompting modelers to stick to a homogeneous dynamic-system decomposition of the target agroecosystem. Most importantly, it provides the conceptual link between biophysical research on ecosystem services and equally important considerations on cognitive and social aspects involved in agricultural and landscape-level decisions that aim at implementing agroecological principles.
文摘Members of the ERF Family of Transcription Factors play an important role in plant development and gene expression that regulates responses to biotic and abiotic stress.This work identified 36 ERF family genes in Coffea arabica within the AP2/ERF full domain,using the EST-based genomic resource of the Brazilian Coffee Genome Project.The ERF family genes were classified into nine of the ten existing groups through phylogenetic analysis of the deduced amino acid sequences and comparison with the sequences of the ERF family genes in Arabidopsis.In addition to the AP2 domain,other conserved domains were identified,typical of members of each group.The in silico analysis and expression profiling showed high levels of expression for libraries derived from tissues of fruits,leaves and flowers as well as for libraries subjected to water stress.These results suggest the participation of the ERF family genes of C.arabica in distinct biological functions,such as control of development,maturation,and responses to water stress.The results of this work imply in the selection of promising genes for further functional characterizations that will provide a better understanding of the complex regulatory networks related to plant development and responses to stress,opening up opportunities for coffee breeding programs.
基金This work was funded by the National Natural Science Foundation of China(41331174,41101415,41301366)Collaborative Innovation Center of Geospatial Technology,Collaborative Innovation Center for Major Ecological Security Issues of Jiangxi Province and Monitoring Implementation(JXS-EW-08)+2 种基金Special Fund by Surveying&Mapping and Geoinformation Research in the Public Interest(201512026),863 Program(2012AA12A304,2012AA12A306)Natural Science Foundation of Hubei Province of China(2015CFB331)Special funds of State Key Laboratory for equipment.Thanks to Jiangxi Provincial Institute of Water Science for providing partial data for this paper.
文摘The Soil and Water Assessment Tool(SWAT)model was used to assess the impacts of different land use scenarios on hydrological processes in the Fuhe watershed in Poyang Lake Basin,East China.A total of 12 model parameters were calibrated with observed monthly runoff data for 1982-1988 and validated for 1991-1998 for baseline conditions.The baseline test results of R2 and Nash-Sutcliffe model efficiency(NSE)values ranged between 0.88 and 0.94 across the calibration and validation periods,indicating that SWAT accurately replicated the Fuhe watershed streamflow.Several different land use scenarios were then simulated with the model,focusing on the impacts of land use change on the hydrology of the watershed.The results of hypothetical scenario simulations revealed that surface runoff declined while groundwater recharge and evapotranspiration(ET)increased,as forest land,agriculture land and/or grassland areas increased,as well as when paddy field and urban areas decreased.These results further showed that forest land has a higher capacity to conserve the water as compared to pasture land.The results of the real scenario simulations revealed that urbanization is the strongest contributor to changes in surface runoff,water yield,and ET.Urbanization can be considered as a potential major environmental stressor controlling hydrological components.
文摘Symbiotic relationships between fungal endophytes and grass species are known to increase stress resistance in the grass host;however,there is little evidence to suggest that the positive effects occur early in the grass life cycle.In this study,we explored the effects of the endophyte Epichloe¨festucae on the growth and survival of Festuca eskia seedlings under drought and frequent cutting stress.Methods Festuca eskia seedlings were collected from the western part of the plant repartition area in a non-symbiotic population located in a mesic and heavily grazed site(W-NS)and from the eastern part in a symbiotic population from a xeric and lightly grazed site(E-S).The E-S population was experimentally freed from its endophyte(E-F).Two greenhouse experiments were conducted to compare growth and survival between the three seedling types under drought stress and frequent cutting.In the first experiment,126 seedlings per seedling type(n=378)were grown for 6 weeks under non-limiting conditions before the cessation of watering.After 3 weeks without irrigation,full irrigation was restored for 10 days to measure the survival rate.Leaf length,leaf elongation rate and survival rate were assessed per population.In the second experiment,156 seedlings per seedling type(n=468)were grown under non-limiting conditions.All seedlings were cut to 3 cmhigh,twice a week,during the first month of growth.Leaf elongation and tillering were monitored on 52 seedlings per seedling type.For each type,seedling survival rate was determined by the number of plants alive after 10 days of regrowth,without cutting.Important Findings The drought experiment revealed a phenotypic differentiation to drought in 30 F.eskia populations,suggesting adaptive differentiation:the eastern seedlings showed the highest survival rate.A tradeoff between growth and survival was highlighted:the highest drought survival rate was associated with the lowest leaf elongation rate under non-limiting water conditions.Endophyte presence in the eastern population increased seedling drought survival.In contrast,cutting survival rate was similar between W-NS and E-S because the presence of the endophyte increased seedling survival to frequent cutting.However,this positive effect came with a cost:the endophyte reduced seedling tillering rate.
基金funded by the National Natural Science Foundation of China(31870286 and 31902013)the Natural Science Foundation of Guangdong Province(2022A1515012278,2017A030313114,2018A030310205,and 2021A1515010528)the General Project of Guangzhou City(201804010031)。
文摘Malformed fruits depreciate a plant’s market value.In tomato(Solanum lycopersicum),fruit malformation is associated with the multi-locule trait,which involves genes regulating shoot apical meristem(SAM)development.The expression pattern of TOPLESS3(SITPL3)throughout SAM development prompted us to investigate its functional significance via RNA interference(RNAi)and clustered regularly interspaced short palindromic repeats/CRISPR-associated nuclease 9(Cas9)-mediated gene editing.Lower SITPL3 transcript levels resulted in larger fruits with more locules and larger SAMs at the 5 d after germination(DAG5)stage.Differentially expressed genes in the SAM of wild-type(WT)and SITPL3-RNAi plants,identified by transcriptome deep sequencing(RNA-seq),were enriched in the gibberellin(GA)biosynthesis and plant hormone signaling pathways.Moreover,exogenous auxin and paclobutrazol treatments rescued the multi-locule phenotype,indicating that SITPL3 affects SAM size by mediating auxin and GA levels in the SAM.Furthermore,SITPL3 interacted with WUSCHEL(SIWUS),which plays an important role in SAM size maintenance.We conducted RNA-seq and DNA affinity purification followed by sequencing(DAP-seq)analyses to identify the genes regulated by SITPL3 and SIWUS in the SAM and to determine how they regulate SAM size.We detected24 overlapping genes regulated by SITPL3 and SIWUS and harboring an SIWUS-binding motif in their promoters.Furthermore,functional annotation revealed a notable enrichment for functions in auxin transport,auxin signal transduction,and GA biosynthesis.Dual-luciferase assays also revealed that SITPL3 enhances SIWUS-mediated regulation(repression and activation)of SIPIN3 and SIGA2 ox4 transcription,indicating that the SITPL3-SIWUS module regulates SAM size by mediating auxin distribution and GA levels,and perturbations of this module result in enlarged SAM.These results provide novel insights into the molecular mechanism of SAM maintenance and locule formation in tomato and highlight the SITPL3-SIWUS module as a key regulator.
文摘Dear Editor Strigolactones (SLs) are novel phytohormones that shape plant architecture by inhibiting shoot branching and regulating root growth, besides their established functions in stimulating seed germination of root-parasitic weeds, such as Striga and Phelipanche species, and inducing hyphal branching in arbuscular mycorrhizal (AM) fungi (AI-Babili and Bouwmeester, 2015). Canonical SLs are divided into strigoland orobanchollike subfamilies with a typical structure consisting of a tricyclic (ABC-ring) and a monocyclic lactone (D-ring), which are connected by an enol ether bridge (Figure 1A and Supplemental Figure 1). SLs are synthesized from carotenoids via carlactone, which lacks the B/C-ring (Alder et al., 2012). In Arabidopsis, carlactone (Figure 1A) is converted by MAX1, a member of the CYP711 family, into carlactonoic acid, after methylation, which, can bind to SL receptor (Abe et al., 2014). In rice, a MAX1 homolog, the carlactone oxidase, introduces B/C-rings into carlactone,
基金supported by the National Natural Science Foundation of China (32022006)the Program for Guangdong"ZhuJiang"Innovation Teams (2019ZT08N628)+6 种基金the Agricultural Science and Technology Innovation Program (ASTIP) (CAAS-XTCX2016001)the special funds for science technology innovation and industrial development of Shenzhen Dapeng New District (PT202101-01)supported by the National Natural Science Foundation of China (32070250)the Natural Science Foundation of Guangdong Province (2020A1515011030)the open research project of"Cross-Cooperative Team"of the Germplasm Bank of Wild Species,Kunming Institute of Botany,Chinese Academy of Sciencessupported by the Natural Science Foundation of Guangdong Province (2022A1515110240)support was provided by IRD and the Agence Nationale de la Recherche (Project SESAM,2010 BLAN 170801).
文摘Plant root-nodule symbiosis(RNS)with mutualistic nitrogen-fixing bacteria is restricted to a single clade of angiosperms,the Nitrogen-Fixing Nodulation Clade(NFNC),and is best understood in the legume family.Nodulating species share many commonalities,explained either by divergence from a common ancestor over 100 million years ago or by convergence following independent origins over that same time period.Regardless,comparative analyses of diverse nodulation syndromes can provide insights into constraints on nodulation—what must be acquired or cannot be lost for a functional symbiosis—and the latitude for Plant Communications Genomic landscape of nodulation variation in the symbiosis.However,much remains to be learned about nodulation,especially outside of legumes.Here,we employed a large-scale phylogenomic analysis across 88 species,complemented by 151 RNA-seq libraries,to elucidate the evolution of RNS.Our phylogenomic analyses further emphasize the uniqueness of the transcription factor NIN as a master regulator of nodulation and identify key muta-tions that affect its function across the NFNC.Comparative transcriptomic assessment revealed nodule-specific upregulated genes across diverse nodulating plants,while also identifying nodule-specific and nitrogen-response genes.Approximately 70%of symbiosis-related genes are highly conserved in the four representative species,whereas defense-related and host-range restriction genes tend to be lineage specific.Our study also identified over 900000 conserved non-coding elements(CNEs),over 300000 of which are unique to sampled NFNC species.NFNC-specific CNEs are enriched with the active H3K9ac mark and are correlated with accessible chromatin regions,thus representing a pool of candidate regula-tory elements for genes involved in RNS.Collectively,our results provide novel insights into the evolution of nodulation and lay a foundation for engineering of RNS traits in agriculturally important crops.