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3.
Can J Microbiol ; 66(7): 413-433, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32396748

RESUMO

The world's population is expected to grow to almost 10 billion by 2050, placing unprecedented demands on agriculture and natural resources. The risk in food security is also aggravated by climate change and land degradation, which compromise agricultural productivity. In recent years, our understanding of the role of microbial communities on ecosystem functioning, including plant-associated microbes, has advanced considerably. Yet, translating this knowledge into practical agricultural technologies is challenged by the intrinsic complexity of agroecosystems. Here, we review current strategies for plant microbiome manipulation, classifying them into three main pillars: (i) introducing and engineering microbiomes, (ii) breeding and engineering the host plant, and (iii) selecting agricultural practices that enhance resident soil and plant-associated microbial communities. In each of these areas, we analyze current trends in research, as well as research priorities and future perspectives.


Assuntos
Agricultura/métodos , Microbiota , Plantas/microbiologia , Microbiologia do Solo , Agricultura/tendências , Ecossistema , Microbiota/genética , Desenvolvimento Vegetal , Raízes de Plantas/microbiologia , Plantas/genética , Rizosfera , Solo
5.
PLoS One ; 15(4): e0231671, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32302331

RESUMO

Water resources are indispensable for all social-economic activities and ecosystem functions. In addition, changes in water resources have great significance for agricultural production. This paper uses five global climate models from CMIP5 to evaluate the future spatiotemporal variation in water resources in China under four RCP scenarios. The results show that the available precipitation significantly decreases due to evapotranspiration. Comparing the four RCP scenarios, the national average of the available precipitation is the highest under the RCP 2.6 and 4.5 scenarios, followed by that under the RCP 8.5 scenario. In terms of spatial distribution, the amount of available precipitation shows a decreasing trend from southeast to northwest. Regarding temporal changes, the available precipitation under RCP 8.5 exhibits a trend of first increasing and then decreasing, while the available precipitation under the RCP 6.0 scenario exhibits a trend of first decreasing and then increasing. Under the RCP 2.6 and 4.5 scenarios, the available precipitation increases, and the RCP 4.5 scenario has a higher rate of increase than that of RCP 2.6. In the context of climate change, changes in water resources and temperature cause widespread increases in potential agricultural productivity around Hu's line, especially in southwestern China. However, the potential agricultural productivity decreases in a large area of southeastern China. Hu's line has a partial breakthrough in the locking of agriculture, mainly in eastern Tibet, western Sichuan, northern Yunnan and northwestern Inner Mongolia. The results provide a reference for the management and deployment of future water resources and can aid in agricultural production in China.


Assuntos
Agricultura/tendências , Mudança Climática , Previsões , Recursos Hídricos/provisão & distribução , China , Conjuntos de Dados como Assunto , Monitoramento Ambiental/estatística & dados numéricos , Modelos Estatísticos , Chuva , Análise Espaço-Temporal
6.
Proc Natl Acad Sci U S A ; 117(14): 7863-7870, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32229568

RESUMO

Nearly 20% of tropical forests are within 100 m of a nonforest edge, a consequence of rapid deforestation for agriculture. Despite widespread conversion, roughly 1.2 billion ha of tropical forest remain, constituting the largest terrestrial component of the global carbon budget. Effects of deforestation on carbon dynamics in remnant forests, and spatial variation in underlying changes in structure and function at the plant scale, remain highly uncertain. Using airborne imaging spectroscopy and light detection and ranging (LiDAR) data, we mapped and quantified changes in forest structure and foliar characteristics along forest/oil palm boundaries in Malaysian Borneo to understand spatial and temporal variation in the influence of edges on aboveground carbon and associated changes in ecosystem structure and function. We uncovered declines in aboveground carbon averaging 22% along edges that extended over 100 m into the forest. Aboveground carbon losses were correlated with significant reductions in canopy height and leaf mass per area and increased foliar phosphorus, three plant traits related to light capture and growth. Carbon declines amplified with edge age. Our results indicate that carbon losses along forest edges can arise from multiple, distinct effects on canopy structure and function that vary with edge age and environmental conditions, pointing to a need for consideration of differences in ecosystem sensitivity when developing land-use and conservation strategies. Our findings reveal that, although edge effects on ecosystem structure and function vary, forests neighboring agricultural plantations are consistently vulnerable to long-lasting negative effects on fundamental ecosystem characteristics controlling primary productivity and carbon storage.


Assuntos
Carbono/metabolismo , Conservação dos Recursos Naturais , Ecossistema , Clima Tropical , Agricultura/tendências , Biomassa , Bornéu , Florestas , Fósforo/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Árvores
7.
Nat Commun ; 11(1): 1258, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32152272

RESUMO

Deforestation can increase the transmission of malaria. Here, we build upon the existing link between malaria risk and deforestation by investigating how the global demand for commodities that increase deforestation can also increase malaria risk. We use a database of trade relationships to link the consumption of deforestation-implicated commodities in developed countries to estimates of country-level malaria risk in developing countries. We estimate that about 20% of the malaria risk in deforestation hotspots is driven by the international trade of deforestation-implicated export commodities, such as timber, wood products, tobacco, cocoa, coffee and cotton. By linking malaria risk to final consumers of commodities, we contribute information to support demand-side policy measures to complement existing malaria control interventions, with co-benefits for reducing deforestation and forest disturbance.


Assuntos
Comércio , Conservação dos Recursos Naturais , Internacionalidade , Malária/transmissão , Agricultura/estatística & dados numéricos , Agricultura/tendências , Conservação dos Recursos Naturais/estatística & dados numéricos , Conservação dos Recursos Naturais/tendências , Ecologia , Economia , Monitoramento Ambiental , Florestas , Geografia , Humanos , Malária/epidemiologia , Modelos Teóricos , Políticas , Fatores de Risco , Árvores , Madeira
10.
Arch Microbiol ; 202(4): 677-693, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31897539

RESUMO

Microbial inoculants are gaining importance for attaining sustainable agricultural production systems. Nutrient supply capacity of soil is diminishing continuously owing to soil erosions, degradation, deposition of salts, undesirable elements and metals, water scarcity or excess and imbalanced nutrient supply system. Numerous complementary microbial inoculation combinations are contributing immensely in the management of plant nutrients by way of fixation, solubilization or transformation in soil. Thus, biological wastes and microbial inoculants are alternatives for nutrient demands to bridge future gaps in. A consortium of microorganisms provides enabling and congenial option to maintain their usable capacity for sufficient durations that heads to the positive impact on the microbial activity of soil for desired activities at the target sites. Increased application of agro-chemicals results in deleterious effect on biological system and dependence of future agriculture on these will lead to deterioration in soil health, threats of pollution of water bodies and cumulative effect of these is making production system highly vulnerable and unstable consequently leading to heavy load on the fiscal system. To ameliorate negative impacts, microorganisms are strongly emerging as alternatives for conserving productive capacity for sustainable productions and financial balance of economies. Microbial inoculants that have assumed definite and significant roles for their specificity and necessity and their use in various combinations have emerged as viable and sustainable options to maintain and even enrich the soil health. Since these microbial inoculants are used under varied farming situations and diverse climates with heterogeneous management skills, their efficacies under field conditions remain variable. Thus, it is never-ending process to identify solutions for constraints and application difficulties and further identify newer microbial inoculants for unexplored areas. Adequate timely and quality access of these inoculants to end users is equally important along with developing their skills to utilize these for witnessing desirable and visible impacts.


Assuntos
Inoculantes Agrícolas , Agricultura/tendências , Fenômenos Fisiológicos Bacterianos , Plantas/microbiologia , Microbiologia do Solo , Crescimento Sustentável
11.
Vet Parasitol ; 278: 108993, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31954273

RESUMO

Livestock in general and dairy sector in particular plays a vital role in the Indian economy and in the socio-economic development of millions of people. Rhipicephalus microplus, a one-host and the most prevalent cattle tick in various agro climatic zones of India. This tick species is responsible for severe economic losses to livestock owners both through the direct effects of blood sucking, injection of toxins and indirectly by transmitting pathogens. Due to inadvertent and indiscriminate use of chemicals to kill ticks, field tick population has developed resistance to almost all chemicals that are used to manage them. The intention of this review is to provide the current status of resistance in ticks, the possible mechanisms of resistance operating in the tick population, factors contributing to the development of resistance and the managemental strategies.


Assuntos
Resistência a Medicamentos , Rhipicephalus/efeitos dos fármacos , Acaricidas/farmacologia , Agricultura/tendências , Animais , Bovinos/parasitologia
12.
Plant Dis ; 104(1): 129-136, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31747352

RESUMO

Gummy stem blight, caused by Stagonosporopsis spp., is a major disease of cucurbits in the United States and China that is managed primarily through the use of fungicides. The objective of this study was to monitor and compare the recent fungicide resistance profiles of Stagonosporopsis spp. in Florida open-field and East China protected-structure production systems. Isolates of Stagonosporopsis spp. were evaluated for sensitivity to the commonly used fungicides azoxystrobin, boscalid, tebuconazole, and thiophanate-methyl at discriminatory rates of 0.096, 0.034, 0.128, and 100 mg/liter, respectively. Isolates were collected from Jiangsu, Jiangxi, Zhejiang, and Anhui provinces in China (n = 69), 12 counties in Florida (n = 89), and one county in Georgia (n = 6). More than 50% of isolates from Florida and East China were resistant to thiophanate-methyl. Boscalid resistance was detected in both isolate collections but was two times more frequent in China. Resistance to azoxystrobin was detected in 66% of isolates in Florida but only 7% in China. Tebuconazole was effective in controlling the mycelia growth of Stagonosporopsis spp. in both collections. The results indicate that both production systems currently face similar challenges related to the development of fungicide resistance in Stagonosporopsis spp. However, the resistance profiles are unique for both production systems.


Assuntos
Agricultura , Ascomicetos , Cucurbita , Farmacorresistência Fúngica , Fungicidas Industriais , Agricultura/tendências , Ascomicetos/efeitos dos fármacos , China , Cucurbita/microbiologia , Florida , Fungicidas Industriais/farmacologia , Georgia , Doenças das Plantas/microbiologia
13.
Arch Microbiol ; 202(4): 665-676, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31781809

RESUMO

Plant beneficial rhizobacteria (PBR) is a group of naturally occurring rhizospheric microbes that enhance nutrient availability and induce biotic and abiotic stress tolerance through a wide array of mechanisms to enhance agricultural sustainability. Application of PBR has the potential to reduce worldwide requirement of agricultural chemicals and improve agro-ecological sustainability. The PBR exert their beneficial effects in three major ways; (1) fix atmospheric nitrogen and synthesize specific compounds to promote plant growth, (2) solubilize essential mineral nutrients in soils for plant uptake, and (3) produce antimicrobial substances and induce systemic resistance in host plants to protect them from biotic and abiotic stresses. Application of PBR as suitable inoculants appears to be a viable alternative technology to synthetic fertilizers and pesticides. Furthermore, PBR enhance nutrient and water use efficiency, influence dynamics of mineral recycling, and tolerance of plants to other environmental stresses by improving health of soils. This report provides comprehensive reviews and discusses beneficial effects of PBR on plant and soil health. Considering their multitude of functions to improve plant and soil health, we propose to call the plant growth-promoting bacteria (PGPR) as PBR.


Assuntos
Agricultura/tendências , Fenômenos Fisiológicos Bacterianos , Plantas/microbiologia , Microbiologia do Solo , Bactérias/metabolismo , Nitrogênio/metabolismo , Desenvolvimento Vegetal , Solo/química , Estresse Fisiológico
14.
Science ; 366(6471)2019 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-31831641

RESUMO

The rapid spread of mobile phones creates potential for sustainably raising agricultural productivity for the 2 billion people living in smallholder farming households. Meta-analyses suggest that providing agricultural information via digital technologies increased yields by 4% and the odds of adopting recommended inputs by 22%. Benefits likely exceed the cost of information transmission by an order of magnitude. The spread of GPS-enabled smartphones could increase these benefits by enabling customized information, thus incentivizing farmers to contribute information to the system. Well-known distortions in markets for information limit the ability of such systems to reach the socially efficient scale through purely commercial means. There is a clear role for public support for digital agricultural extension, but messages designed by agricultural ministries are often difficult for farmers to understand and use. Realizing the potential of mobile communication systems requires feedback mechanisms to enable rigorous testing and continuous improvement.


Assuntos
Agricultura/tendências , Smartphone/tendências , Desenvolvimento Sustentável , Fazendeiros
15.
Artigo em Inglês | MEDLINE | ID: mdl-31816978

RESUMO

The Beijing-Tianji-Hebei region (BTHR) is economically developed and densely populated, but its water resources are extremely scarce. A clear understanding of the decoupling relationship between water footprint and economic growth is conducive to facilitating and realizing the coordinated development of water resources and economic growth in this region. This study calculated the water footprint and other related indicators of BTHR from 2004 to 2017, and objectively evaluated the utilization of water resources in the region. Then, logarithmic mean divisia index (LMDI) method was applied to study the driving factors that resulted in the change of water footprint and their respective effects. Finally, Tapio decoupling model was used to research the decoupling relationships between water footprint and economic growth, and between the driving factors of water footprint and economic growth. There are three main results in this research. (1) The water utilization efficiency in BTHR continues to improve, and the water footprint shows a gradually increasing trend during the research period, among which the agricultural water footprint accounts for a relatively high proportion. (2) The change of water footprint can be attributed to efficiency effect, economic effect, and population effect. Furthermore, efficiency effect is the decisive factor of water footprint reduction and economic effect is the main factor of water footprint increase, while population effect plays a weak role in promoting the increase in water footprint. (3) The decoupling status between water footprint and economic growth show a weak decoupling in most years, while the status between water footprint intensity and economic growth always remains strong decoupling. Moreover, population size and economic growth always show an expansive coupling state. In sum, it is advisable for policy makers to improve water utilization efficiency, especially agricultural irrigation efficiency, to raise residents' awareness of water conservation, and increase the import of water-intensive products, so as to alleviate water shortage and realize the coordinated development of water resources and economic growth in BTHR.


Assuntos
Desenvolvimento Econômico/estatística & dados numéricos , Monitoramento Ambiental , Abastecimento de Água , Agricultura/economia , Agricultura/estatística & dados numéricos , Agricultura/tendências , Estudos de Casos e Controles , China , Humanos , Densidade Demográfica
16.
Environ Monit Assess ; 192(1): 48, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31844992

RESUMO

The devastations and damages caused by climate change are apparent across the globe, specifically in the South Asian region where vulnerabilities to climate change among residents are high and climate change adaptation and mitigation awareness are extremely low. Pakistan's low adaptive capacity due to high poverty rate, limited financial resources and shortage of physical resources, and continual extreme climatic events including varying temperature, continual flooding, melting glaciers, saturation of lakes, earthquakes, hurricanes, storms, avalanches, droughts, scarcity of water, pest diseases, human healthcare issues, and seasonal and lifestyle changes have persistently threatened the ecosystem, biodiversity, human communities, animal habitations, forests, lands, and oceans with a potential to cause further damages in the future. The likely effect of climate change on common residents of Pakistan with comparison to the world and their per capita impact of climate change are terribly high with local animal species such as lions, vultures, dolphins, and tortoise facing extinction regardless of generating and contributing diminutively to global GHG emissions. The findings of the review suggested that GHG emissions cause climate change which has impacted agriculture livestock and forestry, weather trends and patterns, food water and energy security, and society of Pakistan. This review is a sectorial evaluation of climate change mitigation and adaption approaches in Pakistan in the aforementioned sectors and its economic costs which were identified to be between 7 to 14 billion USD per annum. The research suggested that governmental interference is essential for sustainable development of the country through strict accountability of resources and regulation implemented in the past for generating state-of-the-art climate policy.


Assuntos
Mudança Climática , Monitoramento Ambiental , Agricultura/tendências , Animais , Ecossistema , Inundações , Agricultura Florestal , Florestas , Humanos , Gado , Paquistão
18.
Curr Biol ; 29(24): R1326-R1338, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31846685

RESUMO

Global warming is one of the most detrimental aspects of climate change, affecting plant growth and development across the entire life cycle. This Review explores how different stages of development are influenced by elevated temperature in both wild plants and crops. Starting from seed development and germination, global warming will influence morphological adjustments, termed thermomorphogenesis, and photosynthesis primarily during the vegetative phase, as well as flowering and reproductive development. Where applicable, we distinguish between moderately elevated temperatures that affect all stages of plant development and heat waves that often occur during the reproductive phase when they can have devastating consequences for fruit development. The parallel occurrence of elevated temperature with other abiotic and biotic stressors, particularly the combination of global warming and drought or increased pathogen pressure, will potentiate the challenges for both wild and cultivated plant species. The key components of the molecular networks underlying the physiological processes involved in thermal responses in the model plant Arabidopsis thaliana are highlighted. In crops, temperature-sensitive traits relevant for yield are illustrated for winter wheat (Triticum aestivum L.) and soybean (Glycine max L.), representing cultivated species adapted to temperate vs. warm climate zones, respectively. While the fate of wild plants depends on political agendas, plant breeding approaches informed by mechanistic understanding originating in basic science can enable the generation of climate change-resilient crops.


Assuntos
Agricultura/métodos , Agricultura/tendências , Mudança Climática/economia , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Secas , Germinação/genética , Aquecimento Global/economia , Aquecimento Global/estatística & dados numéricos , Desenvolvimento Vegetal/genética , Plântula/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Temperatura , Triticum/crescimento & desenvolvimento
19.
Sci Adv ; 5(11): eaax6656, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31763452

RESUMO

Northern Iraq was the political and economic center of the Neo-Assyrian Empire (c. 912 to 609 BCE)-the largest and most powerful empire of its time. After more than two centuries of regional dominance, the Neo-Assyrian state plummeted from its zenith (c. 670 BCE) to complete political collapse (c. 615 to 609 BCE). Earlier explanations for the Assyrian collapse focused on the roles of internal politico-economic conflicts, territorial overextension, and military defeat. Here, we present a high-resolution and precisely dated speleothem record of climate change from the Kuna Ba cave in northern Iraq, which suggests that the empire's rise occurred during a two-centuries-long interval of anomalously wet climate in the context of the past 4000 years, while megadroughts during the early-mid seventh century BCE, as severe as recent droughts in the region but lasting for decades, triggered a decline in Assyria's agrarian productivity and thus contributed to its eventual political and economic collapse.


Assuntos
Mudança Climática , Clima , Secas , Ecossistema , Chuva , Agricultura/métodos , Agricultura/tendências , Geografia , Humanos , Iraque , Temperatura , Fatores de Tempo
20.
PLoS One ; 14(11): e0221115, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31725716

RESUMO

This study assessed the spatial and temporal variations of land cover in the agricultural areas of the Al-Hassa oasis, Kingdom of Saudi Arabia (KSA). Change detection technique was applied in order to classify variations among different surface cover aspects, during three successive stages between 1985 and 2017 (i.e., 1985 to 1999 (14 years), 1999 to 2013 (14 years), and 2013 to 2017 (4 years)), using two scenarios. During the first stage, significant urban sprawl (i.e., 3,200 ha) occurred on bare lands within the old oasis, while only 590 ha of the oasis's vegetation area was occupied by urban cover. However, the final stage revealed rapid urban development (1,270 ha by 2017) within the oasis's vegetation region, while no urban sprawl occurred on bare lands (area of 1,900 ha, same as that in 1999-2013). Vegetation cover of around 1,000 ha changed to the bare soil class, in addition to the areas that were occupied by the urban class (1,700 ha in total). The study provides quantitative information on the influence of urban development on the spatial changes in vegetation cover of the oasis, especially during recent decades.


Assuntos
Recursos Naturais , Agricultura/tendências , Conservação dos Recursos Naturais/tendências , Monitorização de Parâmetros Ecológicos/métodos , Monitoramento Ambiental/métodos , Sistemas de Informação Geográfica , Tecnologia de Sensoriamento Remoto , Arábia Saudita , Solo , Análise Espaço-Temporal , Urbanização/tendências
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