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1.
World J Microbiol Biotechnol ; 36(2): 23, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31965334

RESUMO

Arsenic naturally occurs in the earth's crust and can be introduced in the environment by human activities. Agricultural practices in arsenic-contaminated environments pose a threat to human health. The contamination of crops contributes to the metalloid's introduction in the food chain. This study aims to test the hypotheses that the inoculation of a hyperaccumulator rhizobacterial strain, Ochrobactrum tritici As5, to the rhizosphere of rice plants reduces the arsenic presence inside the tissue of the rice plants and reduces the inhibitory effect of the metalloid on the plant's growth parameters. Inoculation of the hyperaccumulating strain O. tritici As5 showed the lowest concentration of arsenic in the plant's tissue (2.6 fold lower than sterile plants), compared to the unmodified type O. tritici SCII24 and sterile rice plants. The inoculation of the type strain SCII24 also led to a decrease in arsenic concentration in the plant tissue compared with sterile plants (1.6 fold lower than sterile plants). The difference in arsenic presence in shoots was smaller among treatment groups than in the roots, showing a similar trend. The inoculation of the hyperaccumulator As5 strain alleviated some of the toxic effects of arsenic on shoot growth compared to inoculation of the unmodified type strain. All these findings together, contribute to our understanding of the interplay between arsenic pollution, plants and their rhizobacteria, especially the role of bioaccumulation of metal(oids) by rhizobacteria, and provide important information on the prevention of arsenic uptake by crops and the development of phytostabilizers.


Assuntos
Arsênico/análise , Ochrobactrum/crescimento & desenvolvimento , Oryza/microbiologia , Arsênico/toxicidade , Biodegradação Ambiental , Produtos Agrícolas/química , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/microbiologia , Ochrobactrum/metabolismo , Oryza/química , Oryza/crescimento & desenvolvimento , Brotos de Planta/química , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/microbiologia , Rizosfera , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
2.
J Agric Food Chem ; 68(3): 703-711, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31904950

RESUMO

In crop plants, the yield loss caused by drought exceeds the losses resulting from other adverse environment stresses. In numerous plant species, seedling establishment is positively correlated with the initial seed size under drought stress conditions. In intra- and interspecies, plants with large seeds can withstand water deficiency stresses, whereas those with small seeds are efficient colonizers as a result of their ability to produce more seeds. Therefore, larger initial seeds confer more drought resistance on germinating seedlings. Although this phenomenon has been observed by evolutionary biologists and ecologists, the correlation of initial seed size with the drought resistance of seedlings/plants is not well-reviewed and characterized. Furthermore, the related molecular mechanisms are unknown. Understanding these mechanisms will benefit future breeding or design strategies to increase crop yields. In the present review, we focus on recent research to analyze the genetic factors of plants/crops involved in the regulation of seed size and drought tolerance and their corresponding signal transduction pathways. Several signaling pathways that determine plant drought tolerance through influencing the initial seed size are identified. Such pathways include those that are involved in mitogen-activated protein kinase, abscisic acid, brassinosteroids, and several transcription factors and sugar signaling pathways.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Sementes/química , Produtos Agrícolas/classificação , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Água/análise , Água/metabolismo
3.
J Sci Food Agric ; 100(3): 904-914, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31612486

RESUMO

A huge amount of nitrogenous fertilizer is used to increase crop production. This leads to an increase in the cost of production, and to human and environmental problems. It is therefore necessary to improve nitrogen use efficiency (NUE) and to design agronomic, biotechnological and breeding strategies for better fertilizer use. Nitrogen use efficiency relies primarily on how plants extract, uptake, transport, assimilate, and remobilize nitrogen. Many plants use nitrate as a preferred nitrogen source. It acts as a signaling molecule in the various important physiological processes required for growth and development. As nitrate is the main source of nitrogen in the soil, root nitrate transporters are important subjects for study. The latest reports have also discussed how nitrate transporter and assimilation genes can be used as molecular tools to improve NUE in crops. The purpose of this review is to describe the mechanisms and functions of nitrate as a specific factor that can be addressed to increase NUE. Improving factors such as nitrate uptake, transport, assimilation, and remobilization through activation by signaling, sensing, and regulatory processes will improve plant growth and NUE. © 2019 Society of Chemical Industry.


Assuntos
Produtos Agrícolas/metabolismo , Nitratos/metabolismo , Proteínas de Transporte de Ânions/genética , Proteínas de Transporte de Ânions/metabolismo , Transporte Biológico , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Fertilizantes/análise , Nitrogênio/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
4.
J Sci Food Agric ; 100(1): 25-31, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31471903

RESUMO

Nanotechnology is currently being widely employed in agriculture and horticulture. The most widely investigated and developed factor related to fruit trees is nanofertilizers (NFs), which play very important roles in increasing vegetative growth, improving reproductive growth and flowering, thereby increasing productivity, product quality and ultimately increasing shelf-life and decreasing fruit waste. These nanomaterials, which are generally sprayed at low concentrations on trees at different time intervals and in frequent sessions, are also considered as growth stimulants. Macro- and micro-scale NFs such as zinc, boron, chitosan, and fertilizer nanocomposites such as ZnFeMnB (zinc, iron, manganese, boron), NPKMg (nitrogen, phosphorus, potassium, magnesium), and calcite have been shown to significantly improve the vegetative and reproductive traits of fruit trees such as pomegranate, strawberry, mango, date, coffee and grape. Knowledge on the effects of NFs on fruit trees and biological reasons for their effects on different traits is incomplete and there is an urgent need for extensive research on these topics. © 2019 Society of Chemical Industry.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Frutas/química , Nanotecnologia/métodos , Produção Agrícola , Produtos Agrícolas/química , Fertilizantes/análise , Frutas/crescimento & desenvolvimento
5.
Chemosphere ; 238: 124555, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31454746

RESUMO

Pesticide residues in bee products is still a major issue. However, the relations to botanical source and land use characteristics are not clear. The large variability of residues detected questions the suitability of bee-collected- and other hive materials as indicators for environmental contamination. The aim of our study was to clarify whether different beehive matrices contain similar pesticide residues, and how these are correlated with forage preferences and land use types in foraging areas. We tested bee-collected pollen, beebread, honey, nurse bees and honey bee larvae for the presence of concurrently used agricultural pesticides in Estonia. Samples were collected at the end of May and mid-July to include the main crop in northern region - winter and spring oilseed rape (Brassica napus). We saw that different beehive matrices contained various types of pesticide residues in different proportions: pollen and beebread tended to contain more insecticides and fungicides, whereas herbicides represented the primary contaminant in honey. The variations were related to collection year and time but were not related to crops as basic forage resource nor the land use type. We found few positive correlations between amount of pesticides and proportion of pollen from any particular plant family. None of these correlations were related to any land-use type. We conclude that pesticide residues in different honey bee colony components vary largely in amount and composition. The occurrence rate of pesticide residues was not linked to any particular crop.


Assuntos
Abelhas/efeitos dos fármacos , Brassica napus/crescimento & desenvolvimento , Produtos Agrícolas/crescimento & desenvolvimento , Mel/análise , Resíduos de Praguicidas/análise , Pólen/química , Animais , Brassica napus/efeitos dos fármacos , Produtos Agrícolas/efeitos dos fármacos , Estônia , Estações do Ano
6.
J Sci Food Agric ; 100(4): 1827-1831, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31875429

RESUMO

BACKGROUND: Agriculture is the main means of subsistence for most of the population in developing countries. Crops that can increase their value with in situ processing have a big impact on the small landholder's economics. Moreover, crops such as coffee and cocoa beans have been very important for Ecuadorian farmers. In this study, we wanted to analyze if the climatic conditions exist for growing high-quality tea in Ecuador and determine the areas that will be less affected by global climate change in the future. RESULTS: We used a GIS (geographic information systems) based analysis, together with ecological niche modeling to determine areas in Ecuador where Ceylon and Nilgiris tea varieties could be grown, which will maintain similar ecological conditions in the future, and have a high agricultural aptitude. In total, there are more than 150 000 ha in Ecuador that could be converted to high-quality tea plantations, most of them in the coastal provinces, with some specific areas in the Andean foothills. CONCLUSION: Ecuador has a significant amount of land with the potential to grow high-quality tea, with no significant ecological niche modifications due to climate change in the long-term future. Tea is a viable and potentially highly profitable crop for small landholders and should be considered by local stakeholders. © 2019 Society of Chemical Industry.


Assuntos
Agricultura/economia , Camellia sinensis/crescimento & desenvolvimento , Mudança Climática , Produtos Agrícolas/economia , Produtos Agrícolas/crescimento & desenvolvimento , Ecossistema , Equador
7.
Chemosphere ; 238: 124651, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31472346

RESUMO

A harbour sediment, previously remediated, was tested for soilless strawberry cultivation (Camarosa and Monterey cultivars), as an innovative, cost-effective and environment-friendly approach of sediment management. Sediments were tested as such (TS100) and mixed 1/1 (v/v) with a peat-based commercial substrate (TS50), using the peat-based medium as control (TS0). Substrates were characterized for some physicochemical properties (e.g. density, porosity and water capacity). Minerals (P, Ca, K, Na and Fe), heavy metals (Cu, Zn, Mn, Ni, Cr, Pb and Cd), aliphatic hydrocarbons (C > 12), polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), dibenzodioxins and dibenzofurans were analysed in substrates and fruits. Sugars and organic acids, including the ascorbic, were also determined in fruits, as quality indicators. Notwithstanding remediation, sediments showed concentrations of Zn (206 mg kg-1), C > 12 (86 mg kg-1) and PAHs (47 mg kg-1) exceeding the limits established by the Italian L.D. 152/2006, regulating the contamination of soil in green areas, thus making its relocation in the environment not permitted as such. No evidence of fruit contamination by Cr, Pb and Cd was highlighted. Moreover, Cu, Zn and Ni fruit concentrations were comparable among treatments. Conversely, Mn showed statistically higher concentrations in TS0 fruits (56-57 mg kg-1) compared to those grown in sediment-based substrates (8-20 mg kg-1). Among organic contaminants, only dioxin-like PCBs were determined in fruits, at toxic equivalent concentrations fourfold lower than the limit established by the European Union. TS100 fruits showed a yield reduction from 40 to 70% for Camarosa and Monterey, but higher sugar and ascorbic acid contents.


Assuntos
Produtos Agrícolas/normas , Monitoramento Ambiental , Fragaria/metabolismo , Frutas/química , Sedimentos Geológicos/química , Produtos Agrícolas/química , Produtos Agrícolas/crescimento & desenvolvimento , Fragaria/química , Itália , Metais Pesados/análise , Minerais/análise , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/química
8.
Sci Total Environ ; 701: 134424, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31726412

RESUMO

Over use of N fertilizers, most commonly as urea, had been seriously concerned as a major source of radiative N (Nr) for severe environment impacts through leaching, volatilization, and N2O emission from fertilized croplands. It had been well known that biochar could enhance N retention and use efficiency by crops in amended croplands. In this study, a granular biochar-mineral urea composite (Bio-MUC) was obtained by blending urea with green waste biochar supplemented with clay minerals of bentonite and sepiolite. This Bio-MUC material was firstly characterized by microscopic analyses with FTIR, SEM-EDS and STEM, subsequently tested for N leaching in water in column experiment and for N supply for maize in pot culture, compared to conventional urea fertilizer (UF). Microscopic analyses indicated binding of urea N to particle surfaces of biochar and clay minerals in the Bio-MUC composite. In the leaching experiment over 30 days, cumulative N release as NH4+-N and of dissolved organic carbon (DOC) was significantly smaller by >70% and by 8% from the Bio-MUC than from UF. In pot culture with maize growing for 50 days, total fresh shoot was enhanced by 14% but fresh root by 25% under Bio-MUC compared to UF. This study suggested that N in the Bio-MUC was shown slow releasing in water but maize growth promoting in soil, relative to conventional urea. Such effect could be related mainly to N retention by binding to biochar/mineral surfaces and partly by carbon bonds of urea to biochar in the Bio-MUC. Therefore, biochar from agro-wastes could be used for blending urea as combined organo/mineral urea to replace mineral urea so as to reduce N use and impacts on global Nr. Of course, how such biochar combined urea would impact N process in soil-plant systems deserve further field studies.


Assuntos
Carvão Vegetal/química , Produtos Agrícolas/crescimento & desenvolvimento , Fertilizantes , Nitrogênio/análise , Ureia/química , Solo/química
9.
Ecotoxicol Environ Saf ; 187: 109841, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31677566

RESUMO

Drought stress is one of the extreme effects of climate change causing large losses in production of crop plants. The risk of recurrent droughts has increased in next decades hence, the development of shot-gun, inexpensive and effective approaches is essential to ensure high yield of crops in drought-prone areas of the world. Exogenous application of nutrients such as potassium (K) has been reported to increase abiotic resistance and improve yield in crops however, knowledge regarding interaction of K with osmoprotectants like chitosan (Ct) still remains elusive. Here, we report the effects of individual or combined K (using K2SO4 as a source) or Ct application on growth, physiological processes and antioxidative defense system of sunflower under drought stress. At first, various doses of K (0, 5, 10, 15, 20, 25 g/l) and Ct (0, 0.1, 0.2, 0.3, 0.4, 0.5 g/l) were foliar applied to evaluate their role in improving plant biomass, water status and total chlorophyll in drought-induced seedlings of sunflower. The optimized K (11.48 g/l) and Ct (0.28 g/l) doses were further tested in second experiment to understand the underlying mechanisms of drought tolerance. Foliar K + Ct spray markedly enhanced the leaf gas exchange characteristics, increased proline, soluble proteins, and free amino acids, upregulated antioxidant defense system and helped to maintain plant water status in sunflower exposed to drought stress. The impact of drought stress was more pronounced at vegetative than reproductive stage and positive effects of combined K and Ct application were related to improved physiological and metabolic processes to improve yield and quality of sunflower under drought stress.


Assuntos
Antioxidantes/metabolismo , Quitosana/farmacologia , Secas , Helianthus/efeitos dos fármacos , Potássio/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Biomassa , Clorofila/metabolismo , Mudança Climática , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Helianthus/crescimento & desenvolvimento , Helianthus/metabolismo , Água/metabolismo
10.
Environ Monit Assess ; 191(11): 704, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31673801

RESUMO

In light of ongoing changes in how humans interact with the environment, it is of great importance to quantitatively assess the impact of land use and cover change (LUCC) on ecosystems. Using a variety of methods, we analyzed land-use patterns and ecosystem service values (ESV) in 1990, 2000, and 2010; normalized difference vegetation index (NDVI) from 1982 to 2010 in the arid region of Northwest China; and quantitatively assessed the effects of LUCC on changes in NDVI and ESV. The results indicate the following: (1) From 1990 to 2010, the rate of increase in the amount of cropland and urban land was highest at 19.13% and 18.25%, respectively, followed by the rate for water cover (5.10%) and forest land (3.55%), while grassland experienced a reduction of 2.25%. (2) From 1990 to 2010, the total ESV increased by 1.82%. Changes in the amount of water cover and cropland were responsible for an increase in ESV of 1.42% and 1.10%, respectively, while the change in the amount of grassland was responsible for a decrease of 1.09%. Based on this, it seems likely that climate variability is a substantial cause of change in ESV. (3) From 1982 to 2010, NDVI showed an overall increase, first increasing significantly between 1982 and 2002 and then decreasing somewhat from 2002 to 2010. From 1990 to 2010, the contribution rate of LUCC to change in total NDVI was 26.74%, indicating that the contribution rate of climate variability to NDVI change was up to 73.26%. Therefore, over those 20 years, climate warming and humidification had an important impact on the development of ecosystems in the arid region of Northwest China.


Assuntos
Conservação dos Recursos Naturais/tendências , Produtos Agrícolas/crescimento & desenvolvimento , Monitoramento Ambiental/métodos , Poaceae/crescimento & desenvolvimento , Urbanização/tendências , China , Mudança Climática , Ecossistema , Florestas , Humanos
11.
Sci Total Environ ; 688: 1069-1080, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31726538

RESUMO

Belowground interspecific facilitation and complementarity contribute to the phosphorus (P) uptake advantages in the cereal-legume intercropping system. However, the root morphological and physiological plasticity and, subsequently, the P uptake capability response to light conditions in intercropping systems remain unclear. Soybean was grown under two levels of P application rates in sole and intercropping systems (maize/soybean relay strip intercropping) from 2016 to 2018 in Renshou, southwest of China. As a supplement to the field experiment, soybean was also grown in L-S (simulating the light conditions of sole cropping in the field: light first and then shading) and S-L (simulating the light conditions of intercropping in the field: shading first and then light) light conditions with two levels of P application in 2018 in a pot experiment. After maize harvest (approximately 3/4 of the soybean growth period), light capture in intercropping was higher than sole (ameliorated light conditions in intercropping system), which resulted in an advantage of P uptake in intercropped soybean. Both low P supply and more light capture increased the total root length and root APase activity. The genes GmEXPB2 (which is associated with root growth) and GmACP1 (which is associated with exudation of APase) were highly expressed in plants that captured more light under both P-sufficient and P-deficient conditions. Additionally, more light capture increased the production of lateral roots and the proportion of in the upper 15 cm soil layer roots at the reproductive stage in the field. Across the field and pot experiments, increased root morphological and physiological plasticity were associated with lower P concentrations in the leaves and greater allocation of photosynthates to roots as sucrose. It is suggested that ameliorated light conditions can regulate soybean root growth plasticity and, consequently, P uptake in maize/soybean relay strip intercropping systems, especially in the areas with low solar radiation.


Assuntos
Agricultura/métodos , Luz , Fósforo/metabolismo , Soja/fisiologia , China , Produtos Agrícolas/crescimento & desenvolvimento , Raízes de Plantas , Energia Solar
12.
Nature ; 575(7781): 109-118, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31695205

RESUMO

The current trajectory for crop yields is insufficient to nourish the world's population by 20501. Greater and more consistent crop production must be achieved against a backdrop of climatic stress that limits yields, owing to shifts in pests and pathogens, precipitation, heat-waves and other weather extremes. Here we consider the potential of plant sciences to address post-Green Revolution challenges in agriculture and explore emerging strategies for enhancing sustainable crop production and resilience in a changing climate. Accelerated crop improvement must leverage naturally evolved traits and transformative engineering driven by mechanistic understanding, to yield the resilient production systems that are needed to ensure future harvests.


Assuntos
Produção Agrícola/métodos , Produção Agrícola/estatística & dados numéricos , Produtos Agrícolas/genética , Abastecimento de Alimentos/métodos , Abastecimento de Alimentos/estatística & dados numéricos , Aquecimento Global/estatística & dados numéricos , Desenvolvimento Sustentável/tendências , Aclimatação/genética , Aclimatação/fisiologia , Animais , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/microbiologia , Produtos Agrícolas/virologia , Fertilizantes , Humanos , Doenças das Plantas/genética , Doenças das Plantas/prevenção & controle , Doenças das Plantas/estatística & dados numéricos , Chuva
13.
Ecotoxicol Environ Saf ; 186: 109751, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31600650

RESUMO

In this study, calcium and magnesium substituted strontium nano-hexaferrites (Sr0.96Mg0.02Ca0.02Fe12O19, SrMgCa nano-HF) were synthesized by the sol-gel auto-combustion method and their impact on the nutrient uptake, magnetic character and physiology of barley (Hordeum vulgare L.), a crop plant, was investigated. Structural, microstructural, and magnetic properties of nano-HF were evaluated by using vibrating sample magnetometry (VSM), X-ray diffraction (XRD), scanning electron microscopy (SEM) along with energy-dispersive X-ray (EDX) and elemental mapping techniques. Plants were hydroponically exposed to nano-HF (ranging from 125 to 1000 mg/L) for three weeks. Results showed that the SrMgCa nano-HF application enhanced germination rate (about 20%), tissue growth (about 38%), biomass (about 20%), soluble protein content (about 41%), and chlorophyll pigments (about 33-42%) when compared to the untreated control. In general, the plants showed the highest growth achievement at 125 or 250 mg/L of nano-HF treatment. However, higher doses diminished the growth parameters. Element concentrations and magnetic behavior analyses of plant parts proved that SrMgCa nano-HF with a size of 42.4 nm are up-taken by the plant roots and lead to increase in iron, calcium, magnesium, and strontium contents of leaves, which were about 20, 18, 3, and 60 times higher in 500 mg/L nano-HF-treated leaves than those of control, respectively. Overall, this study shows for the first time that the four elements have been internalized into the plant body through the application of substituted nano-HF. These findings suggest that mineral-substituted nanoparticles can be incorporated into plant breeding programs for the i) enhancement of seed germination and ii) treatment of plants by fighting with mineral deficiencies.


Assuntos
Cálcio/farmacologia , Compostos Férricos/farmacologia , Hordeum/efeitos dos fármacos , Magnésio/farmacologia , Fenômenos Magnéticos , Nanopartículas , Estrôncio/farmacologia , Transporte Biológico , Biomassa , Cálcio/metabolismo , Clorofila/metabolismo , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Produtos Agrícolas/fisiologia , Compostos Férricos/metabolismo , Germinação/efeitos dos fármacos , Hordeum/crescimento & desenvolvimento , Hordeum/metabolismo , Hidroponia , Ferro/metabolismo , Ferro/farmacologia , Magnésio/metabolismo , Minerais/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Estrôncio/metabolismo
14.
Plant Sci ; 289: 110270, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31623775

RESUMO

Nutrient fertilization plays a critical role in maintaining soil fertility and improving crop productivity and quality. Precise nutrient management of horticultural crops is a major challenge worldwide as it relies predominantly on chemical fertilizers. Traditional fertilizers are not only costly for the producer, but may be harmful to humans and the environment. This has led to the search for environmentally friendly fertilizers, particularly those with high nutrient-use efficiency, and nanotechnology is emerging as a promising alternative. Nanofertilizers offer benefits in nutrition management through their strong potential to increase nutrient use efficiency. Nutrients, either applied alone or in combination, are bound to nano-dimensional adsorbents, which release nutrients very slowly as compared to conventional fertilizers. This approach not only increases nutrient-use efficiency, but also minimizes nutrient leaching into ground water. Furthermore, nanofertilizers may also be used for enhancing abiotic stress tolerance and used in combination with microorganisms (the so-called nanobiofertilizers) provide great additional benefits. However, although the benefits of nanofertilizers are undoubtedly opening new approaches towards sustainable agriculture, their limitations should also be carefully considered before market implementation. In particular, the extensive release of nanomaterials into the environment and the food chain may pose a risk to human health. In conclusion, although nanofertilizers use in agriculture is offering great opportunities to improve plant nutrition and stress tolerance to achieve higher yields in a frame of climate change, not all nanomaterials will be equally safe for all applications. The risks of nanofertilizers should be carefully examined before use, and further biotechnological advances are required for a correct and safe application of nanomaterials in agriculture.


Assuntos
Produção Agrícola/métodos , Produtos Agrícolas/crescimento & desenvolvimento , Fertilizantes/análise , Nanotecnologia , Agricultura/instrumentação , Agricultura/métodos , Produção Agrícola/instrumentação
15.
Nat Genet ; 51(10): 1549-1558, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31570895

RESUMO

Domestication of clonally propagated crops such as pineapple from South America was hypothesized to be a 'one-step operation'. We sequenced the genome of Ananas comosus var. bracteatus CB5 and assembled 513 Mb into 25 chromosomes with 29,412 genes. Comparison of the genomes of CB5, F153 and MD2 elucidated the genomic basis of fiber production, color formation, sugar accumulation and fruit maturation. We also resequenced 89 Ananas genomes. Cultivars 'Smooth Cayenne' and 'Queen' exhibited ancient and recent admixture, while 'Singapore Spanish' supported a one-step operation of domestication. We identified 25 selective sweeps, including a strong sweep containing a pair of tandemly duplicated bromelain inhibitors. Four candidate genes for self-incompatibility were linked in F153, but were not functional in self-compatible CB5. Our findings support the coexistence of sexual recombination and a one-step operation in the domestication of clonally propagated crops. This work guides the exploration of sexual and asexual domestication trajectories in other clonally propagated crops.


Assuntos
Ananas/genética , Produtos Agrícolas/genética , Domesticação , Genoma de Planta , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Característica Quantitativa Herdável , Ananas/crescimento & desenvolvimento , Bromelaínas/metabolismo , Produtos Agrícolas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Fenótipo , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Dinâmica Populacional , Açúcares/metabolismo
16.
An Acad Bras Cienc ; 91(3): e20180036, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31553363

RESUMO

This work aimed to determine variance components and genetic parameters, as well as phenotypic, genetic and environmental correlations among black oat (Avena strigosa) families grown in different crop season. Seventy-six black oat families and three controls (BRS Madrugada, BRS Centauro, BRS 139 Neblina) were evaluated in two crop seasons (2016 and 2017), using families with intercalary controls experimental design. The results reveled high potential of black oat families to compose a breeding program, due to families and controls variance were similar, variance components expressed greater genetic variance origin for crop season. Panicle weight and panicle grain weight presented high heritability and, these are correlated with panicle length. Thus, these traits can be used to select superior genotypes. Divergent meteorological conditions between crop seasons expressed few variations among phenotypic, genetic and environmental correlations, and it did not alter magnitude and sense of phenotypic and genetic correlations.


Assuntos
Avena/crescimento & desenvolvimento , Avena/genética , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/genética , Variação Genética , Genótipo , Fenótipo , Estações do Ano
17.
BMC Res Notes ; 12(1): 552, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31470897

RESUMO

OBJECTIVES: Crop production is an important variable in social, economic and environmental analyses. There is an abundance of crop data available for the United States, but we lack a typology of county-level crop production that accounts for production similarities in counties across the country. We fill this gap with a county-level classification of crop production with ten mutually exclusive categories across the contiguous United States. DATA DESCRIPTION: To create the typology we ran a cluster analysis on acreage data for 21 key crops from the United States Department of Agriculture's 2012 Agricultural Census. Prior to clustering, we estimated undisclosed county acreage values, controlled for acreage in other crop types, and removed counties with low agricultural production to produce proportional scores for each crop type in each county. We used proportional scores to control for the influence of county size in the cluster analysis and used internal and stability measures to validate the analysis. The final dataset features 2922 counties. Future research can leverage this typology as an input for county- or regional-level analysis.


Assuntos
Agricultura/métodos , Produtos Agrícolas/crescimento & desenvolvimento , Bases de Dados como Assunto , Estados Unidos
18.
Environ Sci Pollut Res Int ; 26(28): 29409-29423, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31401802

RESUMO

Rice fallow, a rainfed lowland agro-ecology, is presently gaining particular attention for sustainable cropping intensification in the South Asia. Nevertheless, cropping intensification of rice-fallow areas is largely challenged by non-availability of irrigation, the poor financial status of farmers and soil constraints. Indeed, fast depletion of the soil residual moisture remains the primary obstacle for growing a crop in succession in rice fallows. A field investigation was carried out to identify the most adaptable rice-winter crop rotation and to customize appropriate crop establishment practice for a winter crop that could conserve the soil moisture. Treatments comprised of three crop establishment practices for winter crops [utera (relay cropping, i.e. broadcasting of seeds in standing rice crop 15 days before harvesting), zero tillage (ZT) and ZT with mulching (ZTM)], and five post-rainy-season crops (lentil, chickpea, lathyrus, mustard and linseed). Results showed that lathyrus and lentil could be the potential winter crop in the rice-fallow condition of Eastern India. Except for mustard crop, the productivity of all the winter crops was higher in utera cropping, which was primarily attributed to early crop growth and higher soil moisture content over ZT and ZTM treatments. The higher water use efficiency was recorded under utera cropping over ZT and ZTM treatments. Higher system productivity (system rice equivalent yield) in rice-utera lathyrus (9.3 t ha-1) and rice-utera lentil (8.1 t ha-1) led to higher net returns and production efficiency over other treatments (winter crop × crop establishment practice). Benefits of rice residue mulching were prominent in lentil, mustard and linseed crop productivity. Energy use efficiency of different crop establishment practices follows the trend of utera > ZT > ZTM (p < 0.05), being highest in rice-utera lathyrus (5.3) followed by rice-utera lentil (4.8) crop rotations. The simulated data shows that winter crops grown under utera led to less emission of greenhouse gas (GHG) and low global warming potential (GWP) as compared to ZT and ZTM treatments. Rice-lathyrus, rice-lentil and rice-chickpea systems had lower N2O emission than rice-mustard and rice-linseed rotations. Hence, lathyrus and lentil could be included in rice fallows ideally with utera for sustainable cropping intensification and improving the farmers' income in Eastern India.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Óxido Nitroso/análise , Oryza/crescimento & desenvolvimento , Solo/química , Ásia , Produção Agrícola , Aquecimento Global , Gases de Efeito Estufa , Índia , Óxido Nitroso/química , Chuva , Estações do Ano
19.
Int J Mol Sci ; 20(15)2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31370140

RESUMO

The drought is a crucial environmental factor that determines yielding of many crop species, e.g., Fabaceae, which are a source of valuable proteins for food and feed. Herein, we focused on the events accompanying drought-induced activation of flower abscission zone (AZ)-the structure responsible for flower detachment and, consequently, determining seed production in Lupinus luteus. Therefore, detection of molecular markers regulating this process is an excellent tool in the development of improved drought-resistant cultivars to minimize yield loss. We applied physiological, molecular, biochemical, immunocytochemical, and chromatography methods for a comprehensive examination of changes evoked by drought in the AZ cells. This factor led to significant cellular changes and activated AZ, which consequently increased the flower abortion rate. Simultaneously, drought caused an accumulation of mRNA of genes inflorescence deficient in abscission-like (LlIDL), receptor-like protein kinase HSL (LlHSL), and mitogen-activated protein kinase6 (LlMPK6), encoding succeeding elements of AZ activation pathway. The content of hydrogen peroxide (H2O2), catalase activity, and localization significantly changed which confirmed the appearance of stressful conditions and indicated modifications in the redox balance. Loss of water enhanced transcriptional activity of the abscisic acid (ABA) and ethylene (ET) biosynthesis pathways, which was manifested by elevated expression of zeaxanthin epoxidase (LlZEP), aminocyclopropane-1-carboxylic acid synthase (LlACS), and aminocyclopropane-1-carboxylic acid oxidase (LlACO) genes. Accordingly, both ABA and ET precursors were highly abundant in AZ cells. Our study provides information about several new potential markers of early response on water loss, which can help to elucidate the mechanisms that control plant response to drought, and gives a useful basis for breeders and agronomists to enhance tolerance of crops against the stress.


Assuntos
Produtos Agrícolas/genética , Secas , Flores/genética , Regulação da Expressão Gênica de Plantas , Lupinus/genética , Proteínas de Plantas/genética , Sementes/genética , Ácido Abscísico/metabolismo , Adaptação Fisiológica/genética , Catalase/genética , Catalase/metabolismo , Produtos Agrícolas/enzimologia , Produtos Agrícolas/crescimento & desenvolvimento , Etilenos/biossíntese , Flores/enzimologia , Flores/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Peróxido de Hidrogênio , Ligases/genética , Ligases/metabolismo , Lupinus/enzimologia , Lupinus/crescimento & desenvolvimento , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Oxirredução , Oxirredutases/genética , Oxirredutases/metabolismo , Proteínas de Plantas/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Sementes/enzimologia , Sementes/crescimento & desenvolvimento , Estresse Fisiológico/genética
20.
Environ Sci Pollut Res Int ; 26(29): 30167-30176, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31420839

RESUMO

An incubation experiment was conducted to investigate whether the type of crop straw added to soil influenced the temperature sensitivity of soil microbial respiration. The soil for incubation was collected from a winter wheat-soybean rotation cropland. Five temperature levels (5, 10, 15, 20, and 25 °C), five crop straw types (soybean, peanut, rice, winter wheat, and maize), and a control (CK, no crop straw addition) were established. Soil microbial respiration rates were measured on days 1, 2, 3, 5, 7, 10, 14, 20, and 27 after crop straw addition using an infrared CO2 analyser. Soil enzyme activities of invertase, urea, and catalase and the dissolved organic carbon (DOC) content were measured after incubation. Estimated Q10 (temperature sensitivity of soil microbial respiration) ranged from 1.472 ± 0.045 to 1.970 ± 0.020 and showed no significant (P > 0.05) difference between straw addition treatments, but there was significantly (P < 0.001) higher temperature sensitivity (1.970 ± 0.020) for CK. A significant (P = 0.002) relationship was found between the Q10 of cumulative soil microbial respiration and basal soil microbial respiration (soil microbial respiration at 0 °C). Moreover, a marginally significant (P < 0.1) relationship was found between the Q10 at different incubation stages and basal soil microbial respiration. A quadratic function was used to explain the relationship between estimated basal microbial respiration and the lignin content. Soil microbial respiration was positively correlated with the activities of invertase, urease, and catalase and the dissolved organic carbon (DOC) content in all treatments. This study indicated that crop straw addition significantly (P < 0.001) reduced the Q10 of soil microbial respiration and that the types of crop straw added to soil did not significantly (P > 0.05) change the Q10 value.


Assuntos
Produção Agrícola/métodos , Produtos Agrícolas/química , Caules de Planta/química , Microbiologia do Solo , Solo/química , Produtos Agrícolas/crescimento & desenvolvimento , Temperatura Ambiente , Urease/análise , beta-Frutofuranosidase/análise
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