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1.
PLoS One ; 15(12): e0243243, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33332376

RESUMO

The control of plant leaf diseases is crucial as it affects the quality and production of plant species with an effect on the economy of any country. Automated identification and classification of plant leaf diseases is, therefore, essential for the reduction of economic losses and the conservation of specific species. Various Machine Learning (ML) models have previously been proposed to detect and identify plant leaf disease; however, they lack usability due to hardware sophistication, limited scalability and realistic use inefficiency. By implementing automatic detection and classification of leaf diseases in fruit trees (apple, grape, peach and strawberry) and vegetable plants (potato and tomato) through scalable transfer learning on Amazon Web Services (AWS) SageMaker and importing it into AWS DeepLens for real-time functional usability, our proposed DeepLens Classification and Detection Model (DCDM) addresses such limitations. Scalability and ubiquitous access to our approach is provided by cloud integration. Our experiments on an extensive image data set of healthy and unhealthy fruit trees and vegetable plant leaves showed 98.78% accuracy with a real-time diagnosis of diseases of plant leaves. To train DCDM deep learning model, we used forty thousand images and then evaluated it on ten thousand images. It takes an average of 0.349s to test an image for disease diagnosis and classification using AWS DeepLens, providing the consumer with disease information in less than a second.


Assuntos
Computação em Nuvem , Processamento de Imagem Assistida por Computador/métodos , Aprendizado de Máquina , Doenças das Plantas , Folhas de Planta , Algoritmos , Doenças das Plantas/classificação , Folhas de Planta/anatomia & histologia
2.
BMC Plant Biol ; 20(1): 565, 2020 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-33317475

RESUMO

BACKGROUND: Environmental lodging stress, which is a result of numerous factors, is characterized by uncertainty. However, several studies related to lodging in cereal crops have reported that lodging in the Hippeastrum rutilum environment is very rare. Hippeastrum rutilum is a garden flower with high ornamental value and abundant germplasm resources. Under past cultivation practices, it was found that the plant types of 'Red Lion', with red flowers, and 'Apple Blossom', with pink flowers, are quite different. The leaves of 'Red Lion' are upright, while the leaves of 'Apple Blossom' show lodging, which seriously affects its ornamental value. The aims of this study were to compare the differences between the two varieties with leaf lodging and upright leaves according to morphological and physiological attributes. In this study, karyotype analysis and phenotypic morphological and physiological characteristics were compared to explore the differences between the two plant types. RESULTS: The karyotype analysis of the two cultivars showed that their chromosome types were both tetraploid plants. The results showed that the lignin content in the leaves of 'Red Lion' was high, the cross-sectional structure of the leaf vascular bundle was more stable, and the chlorophyll content was high. In addition, significantly less energy was transferred to the electron transport chain (ETR) during the photoreaction. Similarly, the results regarding the maximum photosynthetic rate (Fv/Fm), nonphotochemical quenching (NPQ) and effective quantum yield of photosystem II photochemistry (△F/Fm') all indicated that the photosynthetic capacity of "Red Lion" was greater than that of "Apple Blossom", which was affected by leaf lodging. The size of the leaves was significantly smaller, and the leaf sag angle, leaf width, and leaf tip angle presented significantly lower values in 'Red Lion' than in 'Apple Blossom', which exhibits leaf sag. The difference in these factors may be the reason for the different phenotypes of the two cultivars. CONCLUSION: The results of this study proved that lodging affects the photosynthetic capacity of Hippeastrum rutilum and revealed some indexes that might be related to leaf lodging, laying a theoretical foundation for cultivating and improving new varieties.


Assuntos
Amaryllidaceae/anatomia & histologia , Amaryllidaceae/fisiologia , Amaryllidaceae/genética , Melhoramento Vegetal , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia
3.
BMC Evol Biol ; 20(1): 131, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028198

RESUMO

BACKGROUND: Leaves have highly diverse morphologies. However, with an evolutionary history of approximately 200 million years, leaves of the pine family are relatively monotonous and often collectively called "needles", although they vary in length, width and cross-section shapes. It would be of great interest to determine whether Pinaceae leaves share similar morpho-physiological features and even consistent developmental and adaptive mechanisms. RESULTS: Based on a detailed morpho-anatomical study of leaves from all 11 Pinaceae genera, we particularly investigated the expression patterns of adaxial-abaxial polarity genes in two types of leaves (needlelike and flattened) and compared their photosynthetic capacities. We found that the two types of leaves share conserved spatial patterning of vasculatures and genetic networks for adaxial-abaxial polarity, although they display different anatomical structures in the mesophyll tissue differentiation and distribution direction. In addition, the species with needlelike leaves exhibited better photosynthetic capacity than the species with flattened leaves. CONCLUSIONS: Our study provides the first evidence for the existence of a conserved genetic module controlling adaxial-abaxial polarity in the development of different Pinaceae leaves.


Assuntos
Adaptação Biológica/genética , Fotossíntese , Folhas de Planta/anatomia & histologia , Redes Reguladoras de Genes , Pinaceae , Folhas de Planta/genética
4.
PLoS One ; 15(10): e0239427, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33017404

RESUMO

Plants adapt to high altitudes by adjusting the characteristics of their above and underground organs. Identifying the species-specific plant traits changed in response to altitude is essential for understanding ecophysiological processes at the ecosystem level. Multiple studies analyzed the effects of altitude on above and underground organ traits in different species. Yet, little is known about those responses in the alpine Fritillaria przewalskii Maxim. (Liliaceae). F. przewalskii is a perennial medicinal plant with meager annual growth and vanishing wild populations. We analyzed leaf and bulb functional traits, and their allometric relationships in F. przewalskii plants grown at three altitudes: 3000, 2700, and 2400 m. Leaf thickness, leaf biomass, leaf biomass allocation, and the aboveground:underground ratio increased significantly with increasing altitude. Conversely, bulb allocation decreased at higher altitudes. The altitude influenced the allometric growth trajectories of specific leaf and bulb traits: higher altitudes led to thicker and broader leaves and changed the shape of the bulbs from more circular, which is ideal (at 2700 m), to more elongated (at 3000 m). Those variations had remarkable ecological significance. Hence, bulb biomass is the largest at 2700 m of altitude for which their vertical and longitudinal ratio is unaffected. which is economically favorable. Our findings show that F. przewalskii has a notable potential of growth and morphological plasticity along the altitude gradient and that 2700 m might be ideal for developing its artificial cultivation.


Assuntos
Altitude , Fritillaria/anatomia & histologia , Fritillaria/crescimento & desenvolvimento , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Caules de Planta/anatomia & histologia , Caules de Planta/crescimento & desenvolvimento , Biomassa
5.
PLoS One ; 15(9): e0238589, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32881951

RESUMO

Scanning electron microscopy (SEM) is widely used to investigate the surface morphology, and physiological state of plant leaves. Conventionally used methods for sample preparation are invasive, irreversible, require skill and expensive equipment, and are time and labor consuming. This study demonstrates a method to obtain in vivo surface information of plant leaves by imaging replicas with SEM that is rapid and non-invasive. Dental putty was applied to the leaves for 5 minutes and then removed. Replicas were then imaged with SEM and compared to fresh leaves, and leaves that were processed conventionally by chemical fixation, dehydration and critical point drying. The surface structure of leaves was well preserved on the replicas. The outline of epidermal as well as guard cells could be clearly distinguished enabling determination of stomatal density. Comparison of the dimensions of guard cells revealed that replicas did not differ from fresh leaves, while conventional sample preparation induced strong shrinkage (-40% in length and -38% in width) of the cells when compared to guard cells on fresh leaves. Tilting the replicas enabled clear measurement of stomatal aperture dimensions. Summing up, the major advantages of this method are that it is inexpensive, non-toxic, simple to apply, can be performed in the field, and that results on stomatal density and in vivo stomatal dimensions in 3D can be obtained in a few minutes.


Assuntos
Folhas de Planta/ultraestrutura , Estômatos de Plantas/ultraestrutura , Microscopia Eletrônica de Varredura , Folhas de Planta/anatomia & histologia , Polivinil/química , Siloxanas/química , Tabaco/anatomia & histologia
6.
PLoS One ; 15(9): e0238887, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32913358

RESUMO

Leaf morphology is one of the most important agronomic traits in rice breeding because of its contribution to crop yield. The drooping leaf (dr) mutant was developed from the Ilpum rice cultivar by ethyl methanesulfonate (EMS) mutagenesis. Compared with the wild type, dr plants exhibited drooping leaves accompanied by a small midrib, short panicle, and reduced plant height. The phenotype of the dr plant was caused by a mutation within a single recessive gene on chromosome 2, dr (LOC_Os02g15230), which encodes a GDSL esterase. Analysis of wild-type and dr sequences revealed that the dr allele carried a single nucleotide substitution, glycine to aspartic acid. RNAi targeted to LOC_Os02g15230 produced same phenotypes to the dr mutation, confirming LOC_Os02g15230 as the dr gene. Microscopic observations and plant nutrient analysis of SiO2 revealed that silica was less abundant in dr leaves than in wild-type leaves. This study suggests that the dr gene is involved in the regulation of silica deposition and that disruption of silica processes lead to drooping leaf phenotypes.


Assuntos
Esterases/genética , Oryza/crescimento & desenvolvimento , Dióxido de Silício/metabolismo , Substituição de Aminoácidos , Clonagem Molecular , Esterases/metabolismo , Regulação da Expressão Gênica de Plantas , Mutação , Oryza/genética , Oryza/metabolismo , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sequenciamento Completo do Genoma
7.
Nat Commun ; 11(1): 4519, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908150

RESUMO

The leaf economics spectrum (LES) describes consistent correlations among a variety of leaf traits that reflect a gradient from conservative to acquisitive plant strategies. So far, whether the LES holds in wetland plants at a global scale has been unclear. Using data on 365 wetland species from 151 studies, we find that wetland plants in general show a shift within trait space along the same common slope as observed in non-wetland plants, with lower leaf mass per area, higher leaf nitrogen and phosphorus, faster photosynthetic rates, and shorter leaf life span compared to non-wetland plants. We conclude that wetland plants tend to cluster at the acquisitive end of the LES. The presented global quantifications of the LES in wetland plants enhance our understanding of wetland plant strategies in terms of resources acquisition and allocation, and provide a stepping-stone to developing trait-based approaches for wetland ecology.


Assuntos
Fotossíntese/genética , Folhas de Planta/genética , Plantas/genética , Áreas Alagadas , Nitrogênio/análise , Fósforo/análise , Folhas de Planta/anatomia & histologia , Folhas de Planta/química , Plantas/anatomia & histologia , Plantas/metabolismo
8.
PLoS One ; 15(8): e0237645, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32814345

RESUMO

In this research, an efficient scheme to identify leaf types is proposed. In that scheme, the leaf boundary points are fitted in a continuous contour using Radial Basis Function Neural Networks (RBFNN) to calculate the centroid of the leaf shape. Afterwards, the distances between predetermined points and the centroid were computed and normalized. In addition, the time complexity of the features' extraction algorithm was calculated. The merit of this scheme is objects' independence to translation, rotation and scaling. Moreover, different classification techniques were evaluated against the leaf shape features. Those techniques included two of the most commonly used classification methods; RBFNN and SVM that were evaluated and compared with other researches that used complex features extraction algorithms with much higher dimensionality. Furthermore, a third classification method with an optimization technique for the SVM using Salp Swarm Algorithm (SSA) was utilized showing a significant improvement over RBFNN and SVM.


Assuntos
Algoritmos , Redes Neurais de Computação , Folhas de Planta/anatomia & histologia , Plantas/anatomia & histologia , Plantas/classificação , Máquina de Vetores de Suporte
9.
PLoS One ; 15(7): e0235499, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32628694

RESUMO

In this study, an image-analysis-based method is proposed to estimate the length and width of plant leaves, some of which have concave tips and petiole insertions. Here, kiwifruit leaves are used. Using the proposed method, orthophotographs of the leaves were obtained through image segmentation and image correction. The coordinates of the pixels along the edge of the kiwifruit leaf were then extracted. Finally, the leaf length was determined based on the sum of the number of pixels between the leaf tip and petiole insertion, and the leaf width was calculated based on the sum of the number of pixels for the widest region of the leaf. The experimental results were evaluated by analyzing the mean absolute error (MAE), root mean square error (RMSE), and accuracy. The maximum MAE and RMSE for the three examined cultivars are 0.281 and 0.366 cm, respectively. The analysis also showed that the proposed method outperforms other prevalent approaches, achieving high accuracy rates of 98.88% and 98.83% for the length and width of kiwifruit leaves, respectively. The low MAE and RMSE and high accuracy prove the capability of the proposed method with regard to calculating the length and width of such leaves. In addition, the proposed method can be extended to other plants whose leaf shape is comparable to that of a kiwifruit leaf.


Assuntos
Actinidia/anatomia & histologia , Processamento de Imagem Assistida por Computador , Folhas de Planta/anatomia & histologia
10.
Plant Mol Biol ; 104(3): 249-261, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32715397

RESUMO

Secondary cell wall not only provides rigidity and mechanical resistance to plants, but also has a large impact on plant growth and adaptation to environments. Biosynthesis of secondary cell wall is regulated by a complicated signaling transduction network; however, it is still unclear how the transcriptional regulation of secondary cell wall biosynthesis works at the molecular level. Here, we report in rice that OVATE family proteins 6 (OsOFP6) is a positive regulator in modulating expression of the genes related to biosynthesis of the secondary cell wall. Transgenic plants with knock-down of OsOFP6 by RNA interference showed increased leaf angle, which resulted from the thinner secondary cell wall with reduced amounts of cellulose and lignin, whilst overexpression of OsOFP6 in rice led to the thinker secondary cell wall with increased lignin content. Protein-protein interaction analysis revealed that OsOFP6 interacts with Oryza sativa homeobox 15 (OSH15), a class I KNOX protein. The interaction of OsOFP6 and OSH15 enhanced the transcriptional activity of OSH15 which binds to the promoter of OsIRX9 (Oryza sativa IRREGULAR XYLEM 9). Taken together, our study provides insights into the function of OsOFP6 in regulating leaf angle and the control of biosynthesis of secondary cell wall.


Assuntos
Parede Celular/metabolismo , Oryza/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Parede Celular/ultraestrutura , Celulose/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Homeodomínio/metabolismo , Lignina/metabolismo , Oryza/genética , Folhas de Planta/anatomia & histologia , Folhas de Planta/citologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Regiões Promotoras Genéticas , Domínios e Motivos de Interação entre Proteínas , Interferência de RNA , Proteínas Repressoras/genética , Fatores de Transcrição/genética , Xilema/metabolismo
11.
Nature ; 583(7815): 277-281, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32528176

RESUMO

Plant hormones known as strigolactones control plant development and interactions between host plants and symbiotic fungi or parasitic weeds1-4. In Arabidopsis thaliana and rice, the proteins DWARF14 (D14), MORE AXILLARY GROWTH 2 (MAX2), SUPPRESSOR OF MAX2-LIKE 6, 7 and 8 (SMXL6, SMXL7 and SMXL8) and their orthologues form a complex upon strigolactone perception and play a central part in strigolactone signalling5-10. However, whether and how strigolactones activate downstream transcription remains largely unknown. Here we use a synthetic strigolactone to identify 401 strigolactone-responsive genes in Arabidopsis, and show that these plant hormones regulate shoot branching, leaf shape and anthocyanin accumulation mainly through transcriptional activation of the BRANCHED 1, TCP DOMAIN PROTEIN 1 and PRODUCTION OF ANTHOCYANIN PIGMENT 1 genes. We find that SMXL6 targets 729 genes in the Arabidopsis genome and represses the transcription of SMXL6, SMXL7 and SMXL8 by binding directly to their promoters, showing that SMXL6 serves as an autoregulated transcription factor to maintain the homeostasis of strigolactone signalling. These findings reveal an unanticipated mechanism through which a transcriptional repressor of hormone signalling can directly recognize DNA and regulate transcription in higher plants.


Assuntos
Arabidopsis/genética , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Compostos Heterocíclicos com 3 Anéis/metabolismo , Lactonas/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Transdução de Sinais/genética , Transcrição Genética , Antocianinas/biossíntese , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Genes de Plantas/genética , Reguladores de Crescimento de Planta/biossíntese , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Regiões Promotoras Genéticas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
Nat Commun ; 11(1): 2999, 2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-32532992

RESUMO

Recent studies show coordinated relationships between plant leaf traits and their capacity to predict ecosystem functions. However, how leaf traits will change within species and whether interspecific trait relationships will shift under future environmental changes both remain unclear. Here, we examine the bivariate correlations between leaf economic traits of 515 species in 210 experiments which mimic climate warming, drought, elevated CO2, and nitrogen deposition. We find divergent directions of changes in trait-pairs between species, and the directions mostly do not follow the interspecific trait relationships. However, the slopes in the logarithmic transformed interspecific trait relationships hold stable under environmental changes, while only their elevations vary. The elevation changes of trait relationship are mainly driven by asymmetrically interspecific responses contrary to the direction of the leaf economic spectrum. These findings suggest robust interspecific trait relationships under global changes, and call for linking within-species responses to interspecific coordination of plant traits.


Assuntos
Mudança Climática , Ecossistema , Aquecimento Global , Folhas de Planta/metabolismo , Plantas/metabolismo , Algoritmos , Dióxido de Carbono/metabolismo , Secas , Modelos Biológicos , Nitrogênio/metabolismo , Fenótipo , Folhas de Planta/anatomia & histologia , Plantas/anatomia & histologia , Plantas/classificação , Especificidade da Espécie
13.
Artigo em Inglês | MEDLINE | ID: mdl-32449682

RESUMO

Growing conditions at different tree canopy positions may significantly vary and lead to foliar changes even within the same tree. An assessment of foliar anatomy, including also epidermal features, can help us understand how plants respond to environmental factors. Working with two model tree species (i.e., Quercus petraea and Fagus sylvatica) grown at their southernmost European distribution area in Central Spain, the influence of irradiation and canopy height was examined by sampling lower canopy leaves and comparing them with fully irradiated, top canopy leaves and shaded top canopy leaves grown for months within a bag made of shade netting fabric before they sprouted. At the end of the summer, samples were collected, and several parameters were analysed. The results indicate that SLA (specific leaf area) differences are significant both between species and groups. Leaf and cuticle thickness differed significantly between groups while stomatal densities only between species. Regarding mineral concentrations, differences between species were significant for K, Mn, N and N: P ratios. It is concluded that leaf responses to environmental conditions may be variable both within the same tree and between species.


Assuntos
Fagus , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Quercus , Escuridão , Fotossíntese , Estômatos de Plantas , Espanha , Luz Solar , Árvores
14.
Sci Rep ; 10(1): 6544, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32300153

RESUMO

Single-element transducer based ultrasound (US) imaging offers a compact and affordable solution for high-frequency preclinical and clinical imaging because of its low cost, low complexity, and high spatial resolution compared to array-based US imaging. To achieve B-mode imaging, conventional approaches adapt mechanical linear or sector scanning methods. However, due to its low scanning speed, mechanical linear scanning cannot achieve acceptable temporal resolution for real-time imaging, and the sector scanning method requires specialized low-load transducers that are small and lightweight. Here, we present a novel single-element US imaging system based on an acoustic mirror scanning method. Instead of physically moving the US transducer, the acoustic path is quickly steered by a water-proofed microelectromechanical (MEMS) scanner, achieving real-time imaging. Taking advantage of the low-cost and compact MEMS scanner, we implemented both a tabletop system for in vivo small animal imaging and a handheld system for in vivo human imaging. Notably, in combination with mechanical raster scanning, we could acquire the volumetric US images in live animals. This versatile US imaging system can be potentially used for various preclinical and clinical applications, including echocardiography, ophthalmic imaging, and ultrasound-guided catheterization.


Assuntos
Imageamento Tridimensional , Sistemas Microeletromecânicos/instrumentação , Ultrassonografia , Água , Animais , Feminino , Humanos , Camundongos Endogâmicos BALB C , Imagens de Fantasmas , Folhas de Planta/anatomia & histologia
15.
Mol Phylogenet Evol ; 148: 106809, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32224125

RESUMO

The grape genus (Vitis L.) is of great agronomic importance and represents an economically valuable resource. Researchers have explored the phylogenetic relationships of subgenus Vitis for decades. However, the evolutionary patterns of many morphological characters of subgenus Vitis have not yet been explored in the context of a robust phylogenetic framework. Within the East Asian clade, V. bryoniifolia and its closely related taxa form the V. bryoniifolia clade, which is taxonomically complex. The phylogenetic relationships and species delimitation within this clade remain poorly resolved, due to the limited sampling in prior studies. We tested morphological trait evolution based on ancestral character state reconstruction using a phylogenomic framework. With 89 accessions from the East Asian subgenus Vitis sampled, a robust phylogenetic relationship of the V. bryoniifolia clade is reconstructed using the restriction-site associated DNA sequencing (RAD-seq) data, which support the monophyly of most taxa of the V. bryoniifolia clade. Ancestral character state reconstructions suggest that the weak climbing ability and simplified tendrils of Vitis each evolved multiple times. This study provides a reliable phylogenomic framework for the V. bryoniifolia clade. Coupled with morphological analyses, we discuss the taxonomic status of some taxa in the V. bryoniifolia clade and untangle a taxonomic dilemma in the grape genus.


Assuntos
Filogenia , Característica Quantitativa Herdável , Vitis/anatomia & histologia , Vitis/classificação , Sequência de Bases , Funções Verossimilhança , Fenótipo , Folhas de Planta/anatomia & histologia , Análise de Componente Principal , Análise de Sequência de DNA , Especificidade da Espécie
16.
Ecotoxicol Environ Saf ; 196: 110549, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32251953

RESUMO

Chemicals used to assure agricultural production and the feasibility of planting sites often end up in bodies of water used for crop irrigation. In a pot study, we investigated the consequences associated with the irrigation of maize with water contaminated by ciprofloxacin (Cipro; 0, 0.2, 0.8, 1.4 and 2.0 µg l-1) and/or glyphosate (0, 5, 25 and 50 mg l-1) on yields and food safety. Glyphosate in concentrations ≥25 mg l-1 prevented plant establishment, regardless of Cipro presence. Evaluations made at the V5 stage of plants reveal that Cipro concentrations ≥0.8 µg l-1 and glyphosate decreased photosynthesis and induced changes in leaf anatomy and stem biophysical properties that may contribute to decreased kernel yields. When those chemicals were applied together, kernel yield reductions were accentuated, evidencing their interactive effects. Irrigation with contaminated water resulted in accumulations of Cipro and glyphosate (as well as its metabolite, aminomethylphosphonic acid) in plant tissues. Accumulation of these chemicals in plant tissues such as leaves and kernels is a problem, since they are used to feed animals and humans. Moreover, these chemicals are of potential toxicological concern, principally due to residue accumulations in the food chain. Specially, the antibiotic residue accumulations in maize tissues can assist the induction of antibiotic resistance in dangerous bacteria. Therefore, we point out the urgency of monitoring the quality of water used for crop irrigation to avoid economic and food-quality losses.


Assuntos
Antibacterianos/toxicidade , Ciprofloxacino/toxicidade , Glicina/análogos & derivados , Poluentes Químicos da Água/toxicidade , Zea mays/efeitos dos fármacos , Irrigação Agrícola , Animais , Antibacterianos/farmacocinética , Ciprofloxacino/farmacocinética , Produtos Agrícolas/anatomia & histologia , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/economia , Inocuidade dos Alimentos , Glicina/farmacocinética , Glicina/toxicidade , Humanos , Fotossíntese/efeitos dos fármacos , Folhas de Planta/anatomia & histologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Poluentes Químicos da Água/farmacocinética , Zea mays/anatomia & histologia , Zea mays/metabolismo
17.
Int J Mol Sci ; 21(6)2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32197452

RESUMO

Changes in plant architecture, such as leaf size, leaf shape, leaf angle, plant height, and floral organs, have been major factors in improving the yield of cereal crops. Moreover, changes in grain size and weight can also increase yield. Therefore, screens for additional factors affecting plant architecture and grain morphology may enable additional improvements in yield. Among the basic Helix-Loop-Helix (bHLH) transcription factors in rice (Oryza sativa), we found an enhancer-trap T-DNA insertion mutant of OsbHLH079 (termed osbhlh079-D). The osbhlh079-D mutant showed a wide leaf angle phenotype and produced long grains, similar to the phenotypes of mutants with increased brassinosteroid (BR) levels or enhanced BR signaling. Reverse transcription-quantitative PCR analysis showed that BR signaling-associated genes are largely upregulated in osbhlh079-D, but BR biosynthesis-associated genes are not upregulated, compared with its parental japonica cultivar 'Dongjin'. Consistent with this, osbhlh079-D was hypersensitive to BR treatment. Scanning electron microscopy revealed that the expansion of cell size in the adaxial side of the lamina joint was responsible for the increase in leaf angle in osbhlh079-D. The expression of cell-elongation-associated genes encoding expansins and xyloglucan endotransglycosylases/hydrolases increased in the lamina joints of leaves in osbhlh079-D. The regulatory function of OsbHLH079 was further confirmed by analyzing 35S::OsbHLH079 overexpression and 35S::RNAi-OsbHLH079 gene silencing lines. The 35S::OsbHLH079 plants showed similar phenotypes to osbhlh079-D, and the 35S::RNAi-OsbHLH079 plants displayed opposite phenotypes to osbhlh079-D. Taking these observations together, we propose that OsbHLH079 functions as a positive regulator of BR signaling in rice.


Assuntos
Sequências Hélice-Alça-Hélice , Oryza/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Sementes/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Brassinosteroides/metabolismo , Mutagênese Insercional , Oryza/anatomia & histologia , Oryza/genética , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Proteínas de Plantas/genética , Sementes/anatomia & histologia , Sementes/genética , Fatores de Transcrição/genética
18.
Sci Rep ; 10(1): 4328, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32152443

RESUMO

In biology, structure is the basis of function. For plants, changes in their physiological and ecological functions are usually caused by structural changes. To understand how shading conditions change the plant structures, thereby providing structural insights into the improved yield and quality, oilseed tree peony were shaded with different densities of polyethylene nets from 28 days after pollination (DAP) until harvesting. The thickness of the leaf (LT), vein (VT), upper epidermis (UET), lower epidermis (LET), palisade tissue (PT), sponge tissue (ST), as well as the accumulation and distribution of starch, protein, and fat, were observed at 14-day intervals. The results showed that shading had a significant effect on the anatomical structure of the leaves. In the rapid growth period (before 70 DAP), the LT, ET, and VT under shading were significantly lower than under non-shading. During this period, the accumulation of starch and protein under shading was lower than that under non-shading. At the maturation period (99-112 DAP), the LT and PT under shading were higher than under non-shading, indicating that light shading delayed leaf senescence and increased photosynthetic capacity. Shading delayed the degradation of the integument cells and prolonged seed development and nutrient accumulation.


Assuntos
Paeonia/citologia , Paeonia/efeitos da radiação , Folhas de Planta/citologia , Fenômenos Fisiológicos Vegetais , Sementes/citologia , Luz Solar , Biomarcadores , Células Epidérmicas/citologia , Células Epidérmicas/ultraestrutura , Histocitoquímica , Paeonia/metabolismo , Fenótipo , Fotossíntese , Folhas de Planta/anatomia & histologia , Folhas de Planta/metabolismo , Sementes/anatomia & histologia , Sementes/metabolismo , Estresse Fisiológico
19.
Gene ; 742: 144588, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32179173

RESUMO

Jatropha curcas is an important bioenergy oil plant, and often planted on barren land to save the area of arable land. It is significant to improve the adaptability of J. curcas to various abiotic stresses. In the present study, we transferred a J. curcas gene, encoding a CBF2 transcription factor, into Nicotiana benthamiana. Under drought treatment, the JcCBF2 transgenic lines showed improved survival rate, leaf water retention and active oxygen scavenging capacity, but reduced photosynthesis and transpiration rate, suggesting that JcCBF2 played an important role in improving plant drought tolerance. Overexpressing JcCBF2 decreased leaf area and increased leaf thickness. To explore the possible mechanisms for the change of leaf anatomical structure, the leaves of wild-type and overexpression lines under drought stress were RNA sequenced. Genes involved in the plant hormones signal transduction were found to be enriched. Cytokinin and indole-3-acetic acid were the major plant hormones whose abundance increased. Quantitative RT-PCR analysis showed expression of NbMYB21, NbMYB86 and NbMYB44 and both abscisic acid (ABA) and jasmonic acid (JA) related genes in the overexpression lines were increased under drought stress. These results indicated that JcCBF2 was able to positively regulate plant drought response by changing the leaf anatomical structure and possibly through JA and ABA signalling pathways. Our work may help us to understand the drought tolerant mechanism.


Assuntos
Jatropha/genética , Proteínas de Plantas/genética , Estresse Fisiológico/genética , Tabaco/genética , Transativadores/genética , Secas , Regulação da Expressão Gênica de Plantas , Jatropha/anatomia & histologia , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Tabaco/anatomia & histologia , Tabaco/crescimento & desenvolvimento , Transativadores/metabolismo
20.
PLoS One ; 15(3): e0229912, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32191715

RESUMO

The flag leaf is the main organ of photosynthesis during grain-filling period of wheat, and flag leaf-related traits affect plant morphology and yield potential. In this study, two BC3F6 introgression line (IL) populations derived from the common recipient parent Lumai 14 with Jing 411 and Shaanhan 8675, respectively, were used to map quantitative trait loci (QTL) for flag leaf length (FLL), flag leaf width (FLW), flag leaf area (FLA) and chlorophyll content (CC) at flowering stage and 15 and 20 days after anthesis (DAA) in 2016-2017 (E1) and 2017-2018 (E2) two environments. A total of 14 and 15 QTLs for flag leaf-related traits were detected in Lumai 14 / Jing 411 and Lumai 14 / Shaanhan 8675 populations, respectively. Among them, Both QFLW-6A and QFLA-6A were detected in Lumai 14 / Jing 411 population under E2 and in Lumai 14 / Shaanhan 8675 population under E1 and E2 environments, respectively. QCCS2-3A from Lumai 14 / Jing 411 population and QCCS3-1A, QFLL-4A and QFLL-6A from Lumai 14 / Shaanhan 8675 population were repeatedly identified under two tested environments. Moreover, eight QTL clusters controlling flag leaf-related traits were identified, which provided a genetic basis for significant correlations in phenotype among these traits. On the other hand, positive alleles of QFLW-6A for FLW detected in two populations were derived from their donors. Eighteen lines and 44 lines carried this QTL were found in Lumai 14 / Jing 411 and Lumai 14 / Shaanhan 8675 populations, respectively. The means of FLW in these lines were wider than that of the recipient parent, Lumai 14, in two environments, suggesting that QFLW-6A played an important role for increasing FLW. The IL 124 in Lumai 14 / Jing 411 population and the IL 59 and IL 127 in Lumai 14 / Shaanhan 8675 population had five, five and four donor chromosomal segments which carried no other QTL controlling FLW than QFLW-6A, respectively. And the FLWs of these lines were significantly greater than that of Lumai 14 under two environments. So these lines and their donor parent can be regarded as potential near-isogenic lines. Further, a synteny analysis found QFLW-6A was near the 574,283,851-574,283,613 bp fragment on chromosome 6A and 10 genes were in the range of 500 kb upstream and downstream of the fragment. These results provide the basis for identification of candidate gene and map-based cloning and functional verification of the QTL.


Assuntos
Cromossomos de Plantas/genética , Folhas de Planta/genética , Locos de Características Quantitativas/genética , Triticum/genética , Alelos , Clorofila/genética , Mapeamento Cromossômico , Cruzamentos Genéticos , Grão Comestível/genética , Genótipo , Fenótipo , Fotossíntese/genética , Folhas de Planta/anatomia & histologia , Triticum/crescimento & desenvolvimento
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