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1.
GM Crops Food ; 12(1): 57-70, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32877304

RESUMO

Hybrid seeds of several important crops with supreme qualities including yield, biotic and abiotic stress tolerance have been cultivated for decades. Thus far, a major challenge with hybrid seeds is that they do not have the ability to produce plants with the same qualities over subsequent generations. Apomixis, an asexual mode of reproduction by avoiding meiosis, exists naturally in flowering plants, and ultimately leads to seed production. Apomixis has the potential to preserve hybrid vigor for multiple generations in economically important plant genotypes. The evolution and genetics of asexual seed production are unclear, and much more effort will be required to determine the genetic architecture of this phenomenon. To fix hybrid vigor, synthetic apomixis has been suggested. The development of MiMe (mitosis instead of meiosis) genotypes has been utilized for clonal gamete production. However, the identification and parental origin of genes responsible for synthetic apomixis are little known and need further clarification. Genome modifications utilizing genome editing technologies (GETs), such as clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (cas), a reverse genetics tool, have paved the way toward the utilization of emerging technologies in plant molecular biology. Over the last decade, several genes in important crops have been successfully edited. The vast availability of GETs has made functional genomics studies easy to conduct in crops important for food security. Disruption in the expression of genes specific to egg cell MATRILINEAL (MTL) through the CRISPR/Cas genome editing system promotes the induction of haploid seed, whereas triple knockout of the Baby Boom (BBM) genes BBM1, BBM2, and BBM3 cause embryo arrest and abortion, which can be fully rescued by male-transmitted BBM1. The establishment of synthetic apomixis by engineering the MiMe genotype by genome editing of BBM1 expression or disruption of MTL leads to clonal seed production and heritability for multiple generations. In the present review, we discuss current developments related to the use of CRISPR/Cas technology in plants and the possibility of promoting apomixis in crops to preserve hybrid vigor. In addition, genetics, evolution, epigenetic modifications, and strategies for MiMe genotype development are discussed in detail.


Assuntos
Apomixia , Sistemas CRISPR-Cas , Produtos Agrícolas/genética , Edição de Genes , Vigor Híbrido , Sementes
3.
Wei Sheng Yan Jiu ; 49(5): 840-872, 2020 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-33070833

RESUMO

OBJECTIVE: To analyze the zearalenone(ZEN) level in coix seed, and assess the risk of dietary exposure of ZEN in coix seed in Shanghai. METHODS: The ZEN contents of 147 coix seed samples collected in Shanghai were determined. The consumption data of 730 adults in Shanghai was collected by questionnaire survey with random sampling method. Dietary intake of ZEN from coix seed in Shanghai was simulated by Monte Carlo simulation. RESULTS: The total detection rate of ZEN in coix seed was 69. 39 %(102/147), with the content range of <1. 0-9361 µg/kg and the average value of 327. 7 µg/kg. The average exposure level of populations to ZEN in coix seed was 0. 0216 µg/(kg·d), which was much lower than the tolerable daily intake(TDI). The high exposure level(P95) of populations to ZEN in coix seed was 0. 0609 µg/(kg·d), which accounted for about 24% of TDI. There were about 1. 1% people with the dietary exposure to ZEN exceeding TDI on the basis of the ZEN contents in coix seed and consumption data of coix seed in Shanghai. CONCLUSION: The health risk of ZEN exposure of coix seed in Shanghai population is lower when taking coix seed regularly, and there are potential health risks when taking coix seed highly contaminated with ZEN at a higher dose for a long time.


Assuntos
Coix , Zearalenona , China , Exposição Dietética , Contaminação de Alimentos/análise , Sementes/química , Zearalenona/análise , Zearalenona/toxicidade
4.
BMC Ecol ; 20(1): 49, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32867734

RESUMO

BACKGROUND: Vertebrate-mediated seed dispersal is probably the main long distance dispersal mode. Through endozoochory, large mammals act as mobile links between habitats within and among forest patches. Along with other factors, their feeding regimes do affect their contribution as dispersal vectors. We conducted a cross-species comparative experiment involving two herbivores, red deer and roe deer; and two opportunistic omnivores, wild boar and brown bear, all occurring in the forest and steppe-forest ecotone habitats of the south-eastern Caspian region. We compared their role as endozoochorous seed dispersal agents by monitoring seedling emergence in their dungs under greenhouse and natural conditions. RESULTS: In total, 3078 seedlings, corresponding to 136 plant taxa sprouted from 445 paired dung sub-samples, under greenhouse and natural conditions. Only 336 seedlings, corresponding to 36 plant taxa, emerged under natural conditions, among which five taxa did not appear under greenhouse conditions. Graminoids and forbs composed 91% of the seedlings in the greenhouse whereas shrubs were more abundant under natural conditions, representing 55% of the emerged seedlings. Under greenhouse conditions, first red deer and then wild boar dispersed more species than the other two mammals, while under natural conditions brown bear was the most effective vector. We observed remarkably higher species richness and seedling abundance per dung sub-sample under buffered greenhouse conditions than we did under natural conditions. CONCLUSIONS: The four sympatric mammals studied provided different seed dispersal services, both in terms of seedling abundance and species richness and may therefore be regarded as complementary. Our results highlight a positive bias when only considering germination under buffered greenhouse conditions. This must be taken into account when planning management options to benefit plant biodiversity based on the dispersal services concluded from greenhouse experiments.


Assuntos
Cervos , Dispersão de Sementes , Animais , Germinação , Herbivoria , Plântula , Sementes
5.
Zhongguo Zhong Yao Za Zhi ; 45(16): 3837-3843, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32893578

RESUMO

We used exogenous GA_3 to break the seed dormancy of Thesium chinense. We used high-throughput sequencing technology was used to sequence the transcriptome of dormant seed embryos and dormancy breaking seed embryos of Th. chinense, and the data was analyzed bioinformatically and systematically. The results showed that exogenous GA_3 could effectively break the seed dormancy of Th. chinense; 73 794 up-regulated genes and 42 776 down regulated genes were obtained by transcriptome sequencing; 116 570 diffe-rential genes were annotated by GO function to GO items such as metabolism process, cell process, cell, cell component, binding and catalytic activity. A total of 133 metabolic pathways were found by Pathway analysis of 26 508 differentially expressed genes. In the process of dormancy release, DEGs were mainly enriched in translation, carbohydrate metabolism, folding, classification, degradation and amino acid metabolism. Based on the annotation results in KEGG database, 20 metabolic pathways related to dormancy release were found. Dormancy release of Th. chinense seeds is a complex biological process, including cell morphology construction, secondary metabolite synthesis, sugar metabolism and plant signal transduction, among which plant hormone signal transduction is one of the key factors to regulate dormancy release. The results of qRT-PCR showed that the sequencing results were consistent with the actual results.


Assuntos
Dormência de Plantas , Santalaceae , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Planta , Sementes , Transcriptoma
6.
Int J Periodontics Restorative Dent ; 40(5): e205-e209, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32926006

RESUMO

During a scaling and root planing procedure, a large, actively germinating seed was removed from a deep periodontal pocket. The histologic examination confirmed that it was a germinating tomato seed (Solanum lycopersicum). Since all seeds inside their fruits are in a quiescent stage, this seed was quiescent when the patient ate the tomato. Therefore, the germination occurred inside the periodontal pocket. This case led to a very interesting biologic finding: A periodontal pocket is not only a favorable environment for the development of periodontal microbiota, it is also an ecologic niche that can promote the germination and development of a plant seed.


Assuntos
Germinação , Lycopersicon esculentum , Humanos , Bolsa Periodontal , Aplainamento Radicular , Sementes
7.
Nat Commun ; 11(1): 4663, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938914

RESUMO

Scientific understanding of biodiversity dynamics, resulting from past climate oscillations and projections of future changes in biodiversity, has advanced over the past decade. Little is known about how these responses, past or future, are spatially connected. Analyzing the spatial variability in biodiversity provides insight into how climate change affects the accumulation of diversity across space. Here, we evaluate the spatial variation of phylogenetic diversity of European seed plants among neighboring sites and assess the effects of past rapid climate changes during the Quaternary on these patterns. Our work shows a marked homogenization in phylogenetic diversity across Central and Northern Europe linked to high climate change velocity and large distances to refugia. Our results suggest that the future projected loss in evolutionary heritage may be even more dramatic, as homogenization in response to rapid climate change has occurred among sites across large landscapes, leaving a legacy that has lasted for millennia.


Assuntos
Filogenia , Fenômenos Fisiológicos Vegetais , Biodiversidade , Mudança Climática , Europa (Continente) , Plantas/genética , Refúgio de Vida Selvagem , Sementes
8.
Chemosphere ; 254: 126918, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957302

RESUMO

The increasing application of various surfactants nowadays, may lead to the contamination of the natural environment and represent potential threat to terrestrial higher plants. In this article, the effect of 13 surfactants, with dodecyl alkyl chain and various aromatic (imidazolium, pyridinium, thiazolium) and aliphatic (guanidinium, ammonium, thiosemicarbazidium) polar heads, on germination, development and growth of wheat and cucumber was investigated. The study aimed to prove how changes in lipophilicity of surfactants and their various structural modifications (existence of the aliphatic or aromatic polar group, the introduction of oxygen and sulfur) influence toxicity towards investigated plants. The calculated lipophilic parameter (AlogP) is shown to be a useful parameter for predicting potential toxicity of the compound. The strategy of using surfactants with aliphatic polar heads instead of aromatic prove to be a promising strategy in reducing harmful effect, as well as the introduction of polar groups in the structure of cation. From all investigated compounds, surfactants with imidazolium polar head displayed the most harmful effect towards wheat and cucumber. The cucumber seeds were more sensitive to the addition of surfactants comparing to wheat. All obtained experimental results were additionally investigated using computational methods, simulating the transport of surfactants through a lipid bilayer. The influence of cation tendency to fit in lipid bilayer structure was correlated with toxicity. For the first time, it is concluded that cation ability to mimic the structure of bilayer have less harmful effect on plant development.


Assuntos
Cucumis sativus/efeitos dos fármacos , Imidazóis/toxicidade , Compostos de Piridínio/toxicidade , Tensoativos/toxicidade , Triticum/efeitos dos fármacos , Cátions , Membrana Celular/química , Membrana Celular/efeitos dos fármacos , Cucumis sativus/crescimento & desenvolvimento , Germinação/efeitos dos fármacos , Imidazóis/química , Bicamadas Lipídicas/química , Simulação de Dinâmica Molecular , Compostos de Piridínio/química , Compostos de Piridínio/farmacologia , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Relação Estrutura-Atividade , Tensoativos/química , Triticum/crescimento & desenvolvimento
9.
PLoS One ; 15(9): e0238362, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32877452

RESUMO

Water and nutrient absorption from soil by crops mainly depend on the morphological traits and distribution of the crop roots. Dense planting with reduced nitrogen is a sustainable strategy for improving grain yield and nitrogen use efficiency. However, there is little information on the effects of dense planting with reduced nitrogen on direct-seeded inbred rice. Two-year field experiments were conducted with minirhizotron techniques to characterize the root morphological traits and distributions under different nitrogen application rates and sowing densities in two representative inbred rice varieties, Huanghuazhan (HHZ) and Yuenongsimiao (YNSM), grown under three nitrogen application rates (N0: 0 kg ha-1, LN: 135 kg ha-1, HN: 180 kg ha-1) and two sowing densities (LD: 18.75 kg ha-1, HD: 22.5 kg ha-1). Our study showed that dense planting with low nitrogen improved grain yield partly due to the increased panicle number. The higher sowing density with low nitrogen significantly affected the total root number (TRN), total root length (TRL), total root surface area (TRSA), and total root volume (TRV). There was a significant positive correlation between grain yield and TRL in the 10-20-cm soil layer (P < 0.05). The root morphological indexes were positively correlated with dry matter accumulation (P < 0.05) and negatively correlated with nitrogen content (P < 0.05) at the maturity stage. This study showed that a high sowing density with low nitrogen application can improve root morphology and distribution and increase grain yield and nitrogen use efficiency in direct-seeded inbred rice.


Assuntos
Nitrogênio/farmacologia , Oryza/fisiologia , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/fisiologia , Sementes/fisiologia , Solo/química , Água/química , Oryza/efeitos dos fármacos , Fenótipo , Raízes de Plantas/efeitos dos fármacos , Estações do Ano , Sementes/efeitos dos fármacos
10.
Ecotoxicol Environ Saf ; 204: 111104, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32791360

RESUMO

Since development of antioxidant defence system is high energy demanding event, innate defence system and stress tolerance of plant is strictly governed by plant age. This study is aimed towards evaluating variation of tolerance in germinating seeds and seedlings of Oryza sativa L. cv. Swarna against nano-scale zero valent iron (nZVI). A comparative study of several physiological and biochemical parameters have been carried out among 2 distinct plant groups, Group I treated with variable concentrations of nZVI (50, 100, 150 and 200 mg L-1) during germination and Group II treated with similar nZVI doses on 7th day after germination. Upon treatment with higher nZVI concentrations, Group I seedlings showed susceptibility towards oxidative stress while Group II seedlings showed tolerance against these higher doses of nZVI. Significant growth enhancement was observed upon treatment with 50-150 mg L-1 nZVI, since up-regulation of plant's endogenous antioxidant system protected relatively aged Group II seedlings from oxidative damages. Hierarchical clustering based on overall physiological, biochemical and stress parameters confirmed that in Group I seedlings 100-200 mg L-1 nZVI treatments were toxic where as in Group II seedlings 50-150 mg L-1 nZVI treatments showed growth promoting effects. This differential response is due to developmental stage related resistance in plants.


Assuntos
Germinação/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Oryza/crescimento & desenvolvimento , Antioxidantes/metabolismo , Ferro/metabolismo , Oryza/efeitos dos fármacos , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Plântula/efeitos dos fármacos , Sementes/metabolismo
11.
PLoS One ; 15(8): e0237536, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790719

RESUMO

Melatonin is effective in enhancing various abiotic stress resistances of plants. However, its underlying mechanisms in drought-resistance in winter wheat (Triticum aestivum L.) is not clear. The goal of this work was to investigate the effect of melatonin on seed germination and to evaluate leaf antioxidant physiology for two wheat varieties. Experiments included 20% PEG, melatonin plus 20% PEG and a control using two contrasting wheat varieties (JM22- drought sensitive and HG35- drought resistant). Melatonin levels were 0, 1, 10, 100 and 300 µmol L-1. Results revealed that 300 µmol L-1 of melatonin alleviated the negative effect of water stress on germination and increased radicle length, radicle number, and plumule length of the germinated seeds. Principal component analysis showed a significant change in amino acid content during germination and this change was dependent on melatonin concentration and the variety. Lysine (Lys) content in wheat seeds under the PEG plus 300 µmol L-1 melatonin treatment increased compared with that of the seeds under PEG alone. There was a significant and positive correlation between Lys content and morphological index of germination. During seedling growth, soluble protein was involved in osmotic adjustment and superoxide dismutase (SOD) activity was increased to mitigate the damage in the cytomembrane of JM 22 leaf under 300 µmol L-1 melatonin plus PEG treatment. The effect of melatonin was dependent on SOD activity increasing significantly for HG35-a drought resistant variety. The results of this work lays a foundation for further studies to determine if melatonin can be economically used to mitigate the impact of dry planting conditions on wheat productivity in North China Plain.


Assuntos
Antioxidantes/farmacologia , Germinação/efeitos dos fármacos , Melatonina/farmacologia , Polietilenoglicóis/toxicidade , Sementes/efeitos dos fármacos , Estresse Fisiológico , Triticum/efeitos dos fármacos , Secas , Osmose , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
12.
PLoS One ; 15(8): e0237265, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841240

RESUMO

Roasting is the most common method of processing coffee. During roasting, aromatic compounds are generated due to various reactions, which are important for developing color, flavor and aroma. Acrylamide is an undesirable carcinogenic substance that is metabolically activated and formed during the coffee roasting process. Coffea arabica was first found in Ethiopia, and Ethiopia can produce a large volume of coffee. The major coffee-producing areas in Ethiopia are Hararghe, Sidama, Gimbi/Nekemte, Yergachefe and Limu. The primary purpose of this study was to quantify the acrylamide contents of brewed and roasted coffee collected from street coffee sellers and industrial processors found in Addis Ababa, Ethiopia, and optimize the roasting conditions for Sidama coffee. The acrylamide contents were determined by HPLC using a DAD at 210 nm, the antioxidant property were examined using a UV-spectrophotometer, and moisture and nutrient composition of coffee was determined using the method described by the AOAC (Association of Official Analytical Chemists). The roasting temperature and time were optimized based on the acrylamide content, nutritional composition and antioxidant property of the coffee using central composite design. The roasting temperature and time significantly affected (p<0.05) the acrylamide level, nutritional composition and antioxidant property of the coffee. The acrylamide contents of street and industrial processed powdered coffee were 346 ±19 to 701±38µg/kg and 442±14 to 906±7µg/kg, respectively. Brewed coffee from street vendors and industrial processing had acrylamide contents of 25±2 to 49±1µg/L and 63±2 to 89±4µg/L, respectively. The EC50 values for scavenging radicals for the optimized coffee ranged from 171±0 to 111±4 µg/L. The optimal roasting temperature and time were 190°C and 6 minutes, at this temperature and time the acrylamide content decreased, and the antioxidant and nutritional compositions of the coffee improved.


Assuntos
Acrilamida/análise , Antioxidantes/análise , Coffea/química , Café/química , Nutrientes/análise , Manipulação de Alimentos/métodos , Tecnologia de Alimentos/métodos , Temperatura Alta , Sementes/química
13.
An Acad Bras Cienc ; 92(suppl 1): e20181112, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32756839

RESUMO

This work aimed to study different seeding rates in soybean, at management zones determined by the mapping of the soil apparent electrical conductivity (ECa) and its relationships with plant phenology and grain yield (GY). The experiment consisted of a completely randomized design, with six replications. The plant population ranged between 311,000, 360,000, and 422,000 plants ha-1, and the fixed population (360,000 plants ha-1). The management zone with the least yield potential, received the highest seed population. The management zone with the highest plant vigor potential, received the lowest seed population. The variables plant height, Normalized Difference Vegetation Index (NDVI) at 50, 66, and 92 days after emergence (DAE), one hundred-grain weight, and GY were analyzed. ECa maps can be used to decide the seed population of the soybean. The decision strategy of increasing 20% of the seed soybean population on the smaller ECa map zones, and decreasing 20% seed population on higher ECa zones was effective and resulted in similar GY, even with the negative pressure of the high resistance of penetration (RP) values in some zones. GY map variability was influenced by ECa 0-0.2 m, by NDVI at 92 DAE and by RP 0.4-0.6 m soil layer.


Assuntos
Soja , Condutividade Elétrica , Sementes , Solo
14.
An Acad Bras Cienc ; 92(suppl 1): e20181313, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32756841

RESUMO

Quinoa, classified as a pseudocereal, presents greater nutritional value compared to traditional cereals. Considering the potential for cultivation presented by the species and the benefits of studying plant morphology and morphobiometry, this paper describes seed and seedling morphobiometric characteristics of quinoa (Chenopodium quinoa Willd.) cultivar BRS Piabiru during germination and emergence. To evaluate seed morphobiometry the 1000-seeds weight, moisture content, seed morphological characterization and the tetrazolium test were performed. The morphological characterization of germination and seedling emergence were performed by periodic observations during the development, allowing the description using pictures and drawings. Quinoa seeds cv. BRS Piabiru present an average diameter of 2.05 mm and 1.07 width. 1000-seeds weight of 2.68 g and moisture content of 11%. Externally, quinoa seeds present the pericarp as testa, the hilum and the raphe and, internally, the embryonic axis (cotyledons, radicle and hypocotyl-radicle), perisperm and endosperm. The germination is characterized as epigeal, phanerocotylar type, with radicle protrusion at 3 hours after sowing and complete formed seedlings at 24 hours after sowing. Emergence occurs at 9 days after sowing and plants are completely formed at 12 days after sowing.


Assuntos
Chenopodium quinoa , Germinação , Valor Nutritivo , Plântula , Sementes
15.
Plant Mol Biol ; 104(3): 283-296, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32740897

RESUMO

KEY MESSAGE: Differences in FAE1 enzyme affinity for the acyl-CoA substrates, as well as the balance between the different pathways involved in their incorporation to triacylglycerol might be determinant of the different composition of the seed oil in Brassicaceae. Brassicaceae present a great heterogeneity of seed oil and fatty acid composition, accumulating Very Long Chain Fatty Acids with industrial applications. However, the molecular determinants of these differences remain elusive. We have studied the ß-ketoacyl-CoA synthase from the high erucic feedstock Thlaspi arvense (Pennycress). Functional characterization of the Pennycress FAE1 enzyme was performed in two Arabidopsis backgrounds; Col-0, with less than 2.5% of erucic acid in its seed oil and the fae1-1 mutant, deficient in FAE1 activity, that did not accumulate erucic acid. Seed-specific expression of the Pennycress FAE1 gene in Col-0 resulted in a 3 to fourfold increase of erucic acid content in the seed oil. This increase was concomitant with a decrease of eicosenoic acid levels without changes in oleic ones. Interestingly, only small changes in eicosenoic and erucic acid levels occurred when the Pennycress FAE1 gene was expressed in the fae1-1 mutant, with high levels of oleic acid available for elongation, suggesting that the Pennycress FAE1 enzyme showed higher affinity for eicosenoic acid substrates, than for oleic ones in Arabidopsis. Erucic acid was incorporated to triacylglycerol in the transgenic lines without significant changes in their levels in the diacylglycerol fraction, suggesting that erucic acid was preferentially incorporated to triacylglycerol via DGAT1. Expression analysis of FAE1, AtDGAT1, AtLPCAT1 and AtPDAT1 genes in the transgenic lines further supported this conclusion. Differences in FAE1 affinity for the oleic and eicosenoic substrates among Brassicaceae, as well as their incorporation to triacylglycerol might explain the differences in composition of their seed oil.


Assuntos
3-Oxoacil-(Proteína de Transporte de Acila) Sintase/metabolismo , Biocombustíveis , Vias Biossintéticas , Brassicaceae/metabolismo , Thlaspi/enzimologia , Thlaspi/metabolismo , Triglicerídeos/biossíntese , 1-Acilglicerofosfocolina O-Aciltransferase/metabolismo , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/genética , Aciltransferases/metabolismo , Sequência de Aminoácidos , Proteínas de Arabidopsis/metabolismo , Vias Biossintéticas/genética , Diacilglicerol O-Aciltransferase/metabolismo , Ácidos Erúcicos/metabolismo , Elongases de Ácidos Graxos/genética , Elongases de Ácidos Graxos/metabolismo , Ácidos Graxos/metabolismo , Regulação da Expressão Gênica de Plantas , Fenótipo , Óleos Vegetais/metabolismo , Plantas Geneticamente Modificadas , Sementes/genética , Análise de Sequência , Thlaspi/genética , Transcriptoma
16.
Plant Mol Biol ; 104(3): 263-281, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32740898

RESUMO

KEY MESSAGE: Plant-specific Dof transcription factors VDOF1 and VDOF2 are novel regulators of vascular cell differentiation through the course of a lifetime in Arabidopsis, with shifting their transcriptional target genes. Vascular system is one of critical tissues for vascular plants to transport low-molecular compounds, such as water, minerals, and the photosynthetic product, sucrose. Here, we report the involvement of two Dof transcription factors, named VASCULAR-RELATED DOF1 (VDOF1)/VDOF4.6 and VDOF2/VDOF1.8, in vascular cell differentiation and lignin biosynthesis in Arabidopsis. VDOF genes were expressed in vascular tissues, but the detailed expression sites were partly different between VDOF1 and VDOF2. Vein patterning and lignin analysis of VDOF overexpressors and double mutant vdof1 vdof2 suggested that VDOF1 and VDOF2 would function as negative regulators of vein formation in seedlings, and lignin deposition in inflorescence stems. Interestingly, effects of VDOF overexpression in lignin deposition were different by developmental stages of inflorescence stems, and total lignin contents were increased and decreased in VDOF1 and VDOF2 overexpressors, respectively. RNA-seq analysis of inducible VDOF overexpressors demonstrated that the genes for cell wall biosynthesis, including lignin biosynthetic genes, and the transcription factor genes related to stress response and brassinosteroid signaling were commonly affected by VDOF1 and VDOF2 overexpression. Taken together, we concluded that VDOF1 and VDOF2 are novel regulators of vascular cell differentiation through the course of a lifetime, with shifting their transcriptional target genes: in seedlings, the VDOF genes negatively regulate vein formation, while at reproductive stages, the VDOF proteins target lignin biosynthesis.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Diferenciação Celular/fisiologia , Lignina/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Ligação a DNA , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Inflorescência , Mutação , Caules de Planta/citologia , Caules de Planta/metabolismo , Plantas Geneticamente Modificadas/genética , Sementes , Análise de Sequência
17.
PLoS One ; 15(8): e0231805, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760118

RESUMO

Boron (B) is required during all growth stages of cotton crop, especially during boll formation. However, Typic Haplocambid soils of cotton growing belt in Pakistan are B-deficient, which results in low yield and economic returns. Foliar application of B improves cotton productivity; however, information is limited on the role of soil applied B in improving cotton growth and yield. The current study investigated the role of soil applied B in improving growth, yield and fiber quality of cotton crop. Five different B doses (i.e., 0.00, 2.60, 5.52, 7.78 and 10.04 mg kg-1 of soil) and two cotton cultivars (i.e., CIM-600 and CIM-616) were included in the study. Soil applied B (2.60 mg kg-1) significantly improved growth, yield, physiological parameters and fiber quality, while 10.04 mg kg-1 application improved B distribution in roots, seeds, leaves and stalks. Significant improvement was noted in plant height (12%), leaf area (3%), number of bolls (48%), boll size (59%), boll weight (52%), seed cotton yield (52%), photosynthesis (50%), transpiration rate (10%), stomatal conductance (37%) and water use efficiency (44%) of CIM-600 with 2.60 mg kg-1 compared to control treatment of CIM-616. Similarly, B accumulation in roots, seeds, leaves and stalk of CIM-600 was improved by 76, 41, 86 and 70%, respectively compared to control treatment. The application of 2.60 mg kg-1 significantly improved ginning out turn (6%), staple length (3.5%), fiber fineness (17%) and fiber strength (5%) than no B application. The results indicated that cultivar CIM-600 had higher ginning out turn (1.5%), staple length (5.4%), fiber fineness (15.5%) and fiber strength (1.8%) than CIM-616. In crux, 2.60 mg kg-1 soil B application improved growth, yield, physiological and fiber quality traits of cotton cultivar CIM-600. Therefore, cultivar CIM-600 and 2.60 mg kg-1 soil B application is recommended for higher yield and productivity.


Assuntos
Boro/metabolismo , Gossypium/crescimento & desenvolvimento , Gossypium/metabolismo , Biomassa , Fibra de Algodão/análise , Fertilizantes , Paquistão , Fotossíntese , Folhas de Planta/química , Raízes de Plantas/química , Sementes/química , Solo/química , Água
18.
Pestic Biochem Physiol ; 169: 104647, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32828366

RESUMO

Peptidase inhibitors (PIs) are plant proteins that are found to be effective against various digestive peptidases of insects. The present study isolated and characterized a trypsin inhibitor from mature dry seeds of Mucuna pruriens and investigated its effect against Bactrocera cucurbitae larvae, a major pest of cucurbitaceae crops, for its inhibitory activity. The purified trypsin inhibitor from M. pruriens seeds gave a molecular weight of ~11 kDa on SDS-PAGE. M. pruriens trypsin inhibitor (MPTI) exhibited inhibitory effect on growth of melon fruit fly larvae (64-72 h old) as it resulted in prolongation of larval, pupal and total development period. There was a significant increase in larval mortality with increase in concentration of MPTI. Nutritional indices decreased significantly at all the concentrations of MPTI. Quantitative RT- PCR revealed that the mRNA expression level of trypsin and chymotrypsin genes was reduced while that of GST, esterases, AP, SOD and catalase were enhanced. It can therefore be inferred that MPTI can serve as a promising agent for biocontrol that can reduce the problems caused by fruit fly and other similar catastrophic pests. This study provides the fundamental information for future successful strategies for pest management.


Assuntos
Mucuna , Tephritidae , Animais , Fenômenos Fisiológicos do Sistema Digestório , Larva , Sementes , Inibidores da Tripsina
19.
BMC Ecol ; 20(1): 48, 2020 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-32861248

RESUMO

BACKGROUND: Salvia is a large, diverse, and polymorphous genus of the family Lamiaceae, comprising about 900 ornamentals, medicinal species with almost cosmopolitan distribution in the world. The success of Salvia limbata seed germination depends on a numerous ecological factors and stresses. We aimed to analyze Salvia limbata seed germination under four ecological stresses of salinity, drought, temperature and pH, with application of artificial intelligence modeling techniques such as MLR (Multiple Linear Regression), and MLP (Multi-Layer Perceptron). The S.limbata seeds germination was tested in different combinations of abiotic conditions. Five different temperatures of 10, 15, 20, 25 and 30 °C, seven drought treatments of 0, -2, -4, -6, -8, -10 and -12 bars, eight treatments of salinity containing 0, 50, 100.150, 200, 250, 300 and 350 mM of NaCl, and six pH treatments of 4, 5, 6, 7, 8 and 9 were tested. Indeed 228 combinations were tested to determine the percentage of germination for model development. RESULTS: Comparing to the MLR, the MLP model represents the significant value of R2 in training (0.95), validation (0.92) and test data sets (0.93). According to the results of sensitivity analysis, the values of drought, salinity, pH and temperature are respectively known as the most significant variables influencing S. limbata seed germination. Areas with high moisture content and low salinity in the soil have a high potential to seed germination of S. limbata. Also, the temperature of 18.3 °C and pH of 7.7 are proposed for achieving the maximum number of germinated S. limbata seeds. CONCLUSIONS: Multilayer perceptron model helps managers to determine the success of S.limbata seed planting in agricultural or natural ecosystems. The designed graphical user interface is an environmental decision support system tool for agriculture or rangeland managers to predict the success of S.limbata seed germination (percentage) in different ecological constraints of lands.


Assuntos
Germinação , Salvia , Inteligência Artificial , Ecossistema , Sementes , Temperatura
20.
Phytochemistry ; 178: 112480, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32768716

RESUMO

Paeonia ostii var. lishizhenii has been approved as a woody oil crop with the outstanding characteristic of abundant α-linolenic acid (C18:3, ALA) in its seed oil. The stearoyl-ACP desaturase gene (SAD) regulates the first key step from stearic acid (C18:0, SA) to oleic acid (C18:1, OA) in the ALA biosynthetic pathway, but its functional characterization in P. ostii var. lishizhenii is absent to date. In this study, a key PoSAD gene (1719 bp in length) was acquired from endosperm of P. ostii var. lishizhenii by transcriptome sequencing analysis and the RACE (rapid-amplification of cDNA ends) method. Bioinformatic analysis of the PoSAD protein showed high homology (ranging from 90.4% to 94.4%) and similar physical and chemical properties to SAD from other higher plants, indicating that it encodes a putative stearoyl-ACP desaturase. Analysis of cis-acting elements found several endosperm tissue-specific motifs; i.e., one Prolamin box, thirteen DOFCOREs and one RY repeat in its promoter. The results of the qRT-PCR experiments verified that PoSAD was most highly expressed in developing endosperm at 59 days after pollination (53.7 times that in shoots) compared with that in roots (1.4 times), stems (2.5 times), leaves (3.1 times), petals (13.1 times) and stamens (46.0 times). Meanwhile, the fatty acid contents in P. ostii var. lishizhenii endosperm at seven growth stages were compared with variation in PoSAD expression. Heterologous expression of PoSAD significantly decreased SA and increased OA content, which effectively reduced the ratios of SA to OA in Saccharomyces cerevisiae and Arabidopsis thaliana. However, contents and ratios of palmitic acid (C16:0) and palmitoleic acid (C16:1) were stable in transgenic yeast, and palmitoleic acid remained absent in transgenic A. thaliana seeds. These results illustrate that PoSAD plays an essential role in endosperm development of P. ostii var. lishizhenii, strictly in catalysis of SA desaturation and OA biosynthesis but without functioning in PA desaturation. The results contribute to our understanding of the characterization of PoSAD in OA biosynthesis in P. ostii var. lishizhenii.


Assuntos
Ácido Oleico , Paeonia , Oxigenases de Função Mista , Proteínas de Plantas , Sementes
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