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1.
J Exp Bot ; 75(7): 1872-1886, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38071644

RESUMO

Introgression of resistance genes from wild or related species is a common strategy to improve disease resistance of wheat cultivars. Pm17 is a gene that confers powdery mildew resistance in wheat. It encodes an NLR type of immune receptor and was introgressed from rye to wheat as part of the 1RS chromosome arm translocation several decades ago. So far it has not been possible to separate Pm17 from its co-introgressed rye genes due to suppressed recombination. Here we tested in the field transgenic Bobwhite wheat overexpressing Pm17 without any other rye genes. Four transgenic events showed high levels of PM17 protein accumulation, strong powdery mildew resistance, and no pleiotropic effects during three field seasons. We used a combined approach of transgene insertion and cross-breeding to generate lines co-expressing Pm17 and Pm3, or Pm17 and Pm8. Blumeria graminis f. sp. tritici infection tests confirmed additive, race-specific resistance of the two pyramided transgenes in lines Pm17+Pm3b and Pm17+Pm8. Furthermore, pyramided lines showed strong powdery mildew resistance during three field seasons. We conclude that the combination of overexpressed NLR genes from the extended gene pool broadens and diversifies wheat disease resistance.


Assuntos
Ascomicetos , Triticum , Triticum/genética , Resistência à Doença/genética , Pool Gênico , Ascomicetos/genética , Melhoramento Vegetal , Doenças das Plantas
2.
Avian Pathol ; 53(4): 257-263, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38353105

RESUMO

The aim of the present study was to monitor the dynamics and to measure the safety and efficacy of a live, attenuated, thermosensitive Mycoplasma anserisalpingitidis vaccine candidate, namely MA271, in geese breeder flocks under field conditions. Two rearing flocks were vaccinated with MA271 at 4 weeks of age and boosted at 24 weeks of age by cloaca inoculation (1 ml) and eye-dropping (60 µl). The geese then were transported to multi-aged breeding farms. Two breeding flocks served as controls. Colonization of the cloaca by MA271 showed 75% maximum prevalence between 4 and 6 weeks after the first vaccination. Then the prevalence decreased to 25% until the cooler, humid fall months which coincided with the booster vaccination. Boosting raised cloacal colonization to 100%. No clinical signs were observed in the vaccinated birds. After transportation to five multi-aged breeding farms, the wild-type strain appeared as well as MA271 in three flocks. In one flock, the wild-type strain completely displaced MA271, while in one flock only MA271 was detected. Only wild-type strains were detected in the control flocks; however, due to an HPAI outbreak, both flocks were exterminated before the end of the study. Based on the available data, the median percentage of infertile eggs was 3.7-5.1% in the MA271 vaccinated flocks, and 7.7% in the non-vaccinated flock. In conclusion, MA271 can colonize the cloaca of geese under field conditions. MA271 proved to be safe and presumably protects against M. anserisalpingitidis-induced reproduction losses.


Assuntos
Vacinas Bacterianas , Gansos , Infecções por Mycoplasma , Doenças das Aves Domésticas , Vacinas Atenuadas , Animais , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/microbiologia , Infecções por Mycoplasma/veterinária , Infecções por Mycoplasma/prevenção & controle , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Bacterianas/imunologia , Vacinação/veterinária , Cloaca/microbiologia , Mycoplasma/imunologia , Feminino , Fazendas
3.
Geriatr Nurs ; 55: 339-345, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38159476

RESUMO

OBJECTIVE: The study presented in this paper aimed to assess the effect of an Information Technology enabled community gardening program for older adults, developed by an international consortium. METHODS: We have executed a quantitative, pre- and post-test field trial with older adult volunteers to test the proposed programme in two European countries, Italy and Belgium (n=98). We used standardized and ad hoc questionnaires to measure changes in the volunteers' mental and psychological state during the trial. The statistical data analysis sought for differences in the pre- and post-test values of the key scores related to the perceived quality of life and benefits of gardening via paired-samples t-tests, and also tried to identify the important factors of significant changes via logistic regression. RESULTS: We found significant improvements in the perceived benefits of gardening and also in the scores computed from the WHO Quality of Life instruments, especially in the social sub-domains. The improvements were associated with the country, age, marital state and education of the volunteers. Higher age or being widow, divorced or single increased the odds of a significant improvement in the scores in more than one sub-domains. CONCLUSION: Though the two trial settings were different in some aspects, the observed significant improvements generally confirmed the positive effects of gardening concerning the perceived quality of life and benefits of gardening.


Assuntos
Tecnologia da Informação , Qualidade de Vida , Humanos , Idoso , Jardinagem , Atividades de Lazer , Itália
4.
Planta ; 257(4): 81, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36917306

RESUMO

MAIN CONCLUSION: The pool of carbon- and nitrogen-rich metabolites is quantitatively relevant in non-foliar photosynthetic organs during grain filling, which have a better response to water limitation than flag leaves. The response of durum wheat to contrasting water regimes has been extensively studied at leaf and agronomic level in previous studies, but the water stress effects on source-sink dynamics, particularly non-foliar photosynthetic organs, is more limited. Our study aims to investigate the response of different photosynthetic organs to water stress and to quantify the pool of carbon and nitrogen metabolites available for grain filling. Five durum wheat varieties were grown in field trials in the Spanish region of Castile and León under irrigated and rainfed conditions. Water stress led to a significant decrease in yield, biomass, and carbon and nitrogen assimilation, improved water use efficiency, and modified grain quality traits in the five varieties. The pool of carbon (glucose, glucose-6-phosphate, fructose, sucrose, starch, and malate) and nitrogen (glutamate, amino acids, proteins and chlorophylls) metabolites in leaf blades and sheaths, peduncles, awns, glumes and lemmas were also analysed. The results showed that the metabolism of the blades and peduncles was the most susceptible to water stress, while ear metabolism showed higher stability, particularly at mid-grain filling. Interestingly, the total metabolite content per organ highlighted that a large source of nutrients, which may be directly involved in grain filling, are found outside the blades, with the peduncles being quantitatively the most relevant. We conclude that yield improvements in our Mediterranean agro-ecosystem are highly linked to the success of shoots in producing ears and a higher number of grains, while grain filling is highly dependent on the capacity of non-foliar organs to fix CO2 and N. The ear organs show higher stress resilience than other organs, which deserves our attention in future breeding programmes.


Assuntos
Desidratação , Triticum , Triticum/fisiologia , Desidratação/metabolismo , Ecossistema , Melhoramento Vegetal , Carbono/metabolismo , Folhas de Planta/metabolismo , Grão Comestível/metabolismo , Nitrogênio/metabolismo
5.
Plant Biotechnol J ; 21(5): 1005-1021, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36668687

RESUMO

Trees constitute promising renewable feedstocks for biorefinery using biochemical conversion, but their recalcitrance restricts their attractiveness for the industry. To obtain trees with reduced recalcitrance, large-scale genetic engineering experiments were performed in hybrid aspen blindly targeting genes expressed during wood formation and 32 lines representing seven constructs were selected for characterization in the field. Here we report phenotypes of five-year old trees considering 49 traits related to growth and wood properties. The best performing construct considering growth and glucose yield in saccharification with acid pretreatment had suppressed expression of the gene encoding an uncharacterized 2-oxoglutarate-dependent dioxygenase (2OGD). It showed minor changes in wood chemistry but increased nanoporosity and glucose conversion. Suppressed levels of SUCROSE SYNTHASE, (SuSy), CINNAMATE 4-HYDROXYLASE (C4H) and increased levels of GTPase activating protein for ADP-ribosylation factor ZAC led to significant growth reductions and anatomical abnormalities. However, C4H and SuSy constructs greatly improved glucose yields in saccharification without and with pretreatment, respectively. Traits associated with high glucose yields were different for saccharification with and without pretreatment. While carbohydrates, phenolics and tension wood contents positively impacted the yields without pretreatment and growth, lignin content and S/G ratio were negative factors, the yields with pretreatment positively correlated with S lignin and negatively with carbohydrate contents. The genotypes with high glucose yields had increased nanoporosity and mGlcA/Xyl ratio, and some had shorter polymers extractable with subcritical water compared to wild-type. The pilot-scale industrial-like pretreatment of best-performing 2OGD construct confirmed its superior sugar yields, supporting our strategy.


Assuntos
Lignina , Populus , Lignina/metabolismo , Populus/genética , Populus/metabolismo , Madeira/genética , Madeira/metabolismo , Glucose/metabolismo , Engenharia Genética
6.
Int J Mol Sci ; 24(20)2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37895028

RESUMO

In this work, we present the results of the inoculation of canola seeds (Brassica napus L.) with Trichoderma viride strains that promote the growth of plants. Seven morphologically different strains of T. viride (TvI-VII) were shown to be capable of synthesizing auxins and exhibited cellulolytic and pectinolytic activities. To gain a deeper insight into the molecular mechanisms underlying canola-T. viride interactions, we analyzed the canola stress genes metallothioneins (BnMT1-3) and stringent response genes (BnRSH1-3 and BnCRSH). We demonstrated the presence of cis-regulatory elements responsive to fungal elicitors in the promoter regions of B. napus MT and RSH genes and observed changes in the levels of the transcripts of the above-mentioned genes in response to root colonization by the tested fungal strains. Of the seven tested strains, under laboratory conditions, T. viride VII stimulated the formation of roots and the growth of canola seedlings to the greatest extent. An experiment conducted under field conditions during drought showed that the inoculation of canola seeds with a suspension of T. viride VII spores increased yield by 16.7%. There was also a positive effect of the fungus on the height and branching of the plants, the number of siliques, and the mass of a thousand seeds. We suggest that the T. viride strain TvVII can be used in modern sustainable agriculture as a bioinoculant and seed coating to protect B. napus from drought.


Assuntos
Brassica napus , Hypocreales , Brassica napus/metabolismo , Secas , Plântula/genética
7.
J Environ Manage ; 328: 116973, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36525735

RESUMO

Microalgae appear to be a promising and ecologically safe way for nutrients removal from rare earth tailings (REEs) wastewater with CO2 fixation and added benefits of resource recovery and recycling. In this study, a pilot scale (50 L) co-flocculating microalgae photobioreactor (Ma-PBR) as constructed and operated for 140 days to treat REEs wastewater with low C/N ratio of 0.51-0.56. The removal rate of ammonia nitrogen (NH4+-N) reached 88.04% and the effluent residual concentration was as low as 9.91 mg/L that have met the Emission Standards of Pollutants from Rare Earths Industry (GB 26451-2011). Timely supplementation of trace elements was necessary to maintain the activity of microalgae and then prolonged the operation time. The dominant phyla in co-flocculating microalgae was Chlorophyta, the relative abundance of which was higher than 80%. Tetradesmus belonging to Chlorophyceae was the dominant genus with relative abundance of 80.35%. The results provided a practical support for the scaling-up of Ma-PBR to treat REEs wastewater.


Assuntos
Metais Terras Raras , Microalgas , Águas Residuárias , Fotobiorreatores , Projetos Piloto , Biomassa , Nitrogênio
8.
World J Microbiol Biotechnol ; 39(12): 340, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37821760

RESUMO

Fusarium graminearum, a devastating fungal pathogen, is the main pathogen of Fusarium head blight (FHB) in wheat globally; it results in significant yield loss and mycotoxin contamination that severely threatens global wheat production and food safety. However, despite ongoing efforts, controlling this pathogen still remains a major challenge. Surfactin, primarily synthesized by Bacillus sp. via non-ribosomal peptide synthetases, exhibits potent surfactant and antibacterial properties, but its antifungal mechanism has yet to be fully elucidated. We found that the EC50 of surfactin against hyphal growth of F. graminearum was 102.1 µg/mL, and control efficacy against wheat FHB under field conditions achieved 86.38% in wheat cultivar Huaimai 40 and 81.60% in wheat cultivar Zhoumai 36, indicating that surfactin has potential antifungal activity against F. graminearum. Accumulated intracellular ROS, decreased mitochondrial membrane potential (MMP), activated metacaspase activity and condensed chromatin, were induced by surfactin in F. graminearum hyphae, suggesting that growth inhibition of fungus is mainly caused by apoptosis-like cell death. Furthermore, accumulated intracellular ROS was evidenced to act as a key mediator of surfactin-induced apoptosis. Broad-spectrum caspase inhibitor Z-VAD-FMK treatment indicated that surfactin induces caspase-independent apoptosis in F. graminearum. Collectively, this study provides evidence that surfactin induces a ROS-mediated mitochondrial apoptosis in F. graminearum hyphae, and may exert its antifungal activity against F. graminearum by activating apoptosis. This study demonstrates the potential of surfactin as an antifungal agent for FHB biocontrol, provides a new perspective on the antifungal mechanism of surfactin against filamentous fungi, and contributes to the application of surfactin-producing microbes in the biocontrol of plant diseases.


Assuntos
Antifúngicos , Fusarium , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Apoptose , Caspases , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia
9.
Plant Biotechnol J ; 20(8): 1606-1621, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35514029

RESUMO

Genetically enhancing drought tolerance and nutrient use efficacy enables sustainable and stable wheat production in drought-prone areas exposed to water shortages and low soil fertility, due to global warming and declining natural resources. In this study, wheat plants, exhibiting improved drought tolerance and N-use efficacy, were developed by introducing GmTDN1, a gene encoding a DREB-like transcription factor, into two modern winter wheat varieties, cv Shi4185 and Jimai22. Overexpressing GmTDN1 in wheat resulted in significantly improved drought and low-N tolerance under drought and N-deficient conditions in the greenhouse. Field trials conducted at three different locations over a period of 2-3 consecutive years showed that both Shi4185 and Jimai22 GmTDN1 transgenic lines were agronomically superior to wild-type plants, and produced significantly higher yields under both drought and N-deficient conditions. No yield penalties were observed in these transgenic lines under normal well irrigation conditions. Overexpressing GmTDN1 enhanced photosynthetic and osmotic adjustment capacity, antioxidant metabolism, and root mass of wheat plants, compared to those of wild-type plants, by orchestrating the expression of a set of drought stress-related genes as well as the nitrate transporter, NRT2.5. Furthermore, transgenic wheat with overexpressed NRT2.5 can improve drought tolerance and nitrogen (N) absorption, suggesting that improving N absorption in GmTDN1 transgenic wheat may contribute to drought tolerance. These findings may lead to the development of new methodologies with the capacity to simultaneously improve drought tolerance and N-use efficacy in cereal crops to ensure sustainable agriculture and global food security.


Assuntos
Secas , Triticum , Regulação da Expressão Gênica de Plantas , Fotossíntese , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Triticum/genética , Triticum/metabolismo
10.
New Phytol ; 236(6): 2075-2090, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35808905

RESUMO

Lignin is one of the main factors causing lignocellulosic biomass recalcitrance to enzymatic hydrolysis. Glasshouse-grown poplars severely downregulated for CINNAMYL ALCOHOL DEHYDROGENASE 1 (CAD1), the enzyme catalysing the last step in the monolignol-specific branch of lignin biosynthesis, have increased saccharification yields and normal growth. Here, we assess the performance of these hpCAD poplars in the field under short rotation coppice culture for two consecutive rotations of 1 yr and 3 yr. While 1-yr-old hpCAD wood had 10% less lignin, 3-yr-old hpCAD wood had wild-type lignin levels. Because of their altered cell wall composition, including elevated levels of cinnamaldehydes, both 1-yr-old and 3-yr-old hpCAD wood showed enhanced saccharification yields upon harsh alkaline pretreatments (up to +85% and +77%, respectively). In contrast with previous field trials with poplars less severely downregulated for CINNAMYL ALCOHOL DEHYDROGENASE (CAD), the hpCAD poplars displayed leaning phenotypes, early bud set, early flowering and yield penalties. Moreover, hpCAD wood had enlarged vessels, decreased wood density and reduced relative and free water contents. Our data show that the phenotypes of CAD-deficient poplars are strongly dependent on the environment and underpin the importance of field trials in translating basic research towards applications.


Assuntos
Lignina , Populus , Populus/genética , Oxirredutases do Álcool , Biomassa
11.
Transgenic Res ; 31(4-5): 579-591, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35997870

RESUMO

Drought is an abiotic stress that limits plant growth and productivity, and the development of trees with improved drought tolerance is expected to expand potential plantation areas and to promote sustainable development. Previously we reported that transgenic poplars (Populus tremula × P. tremuloides, T89) harboring the stress-responsive galactinol synthase gene, AtGolS2, derived from Arabidopsis thaliana were developed and showed improved drought stress tolerance in laboratory conditions. Herein we report a field trial evaluation of the AtGolS2-transgenic poplars. The rainfall-restricted treatments on the poplars started in late May 2020, 18 months after transplanting to the field, and were performed for 100 days. During these treatments, the leaf injury levels were observed by measuring photosynthetic quantum yields twice a week. Observed leaf injury levels varied in response to soil moisture fluctuation and showed a large difference between transgenic and non-transgenic poplars during the last month. Comparison of the leaf injury levels against three stress classes clustered by the machine learning approach revealed that the transgenic poplars exhibited significant alleviation of leaf injuries in the most severe stress class. The transgenes and transcript levels were stable in the transgenic poplars cultivated in the field conditions. These results indicated that the overexpression of AtGolS2 significantly improved the drought stress tolerance of transgenic poplars not only in the laboratory but also in the field. In future studies, molecular breeding using AtGolS2 will be an effective method for developing practical drought-tolerant forest trees.


Assuntos
Arabidopsis , Populus , Arabidopsis/genética , Arabidopsis/metabolismo , Secas , Galactosiltransferases , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Populus/genética , Solo , Estresse Fisiológico/genética , Árvores/genética , Árvores/metabolismo
12.
Pestic Biochem Physiol ; 184: 105102, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35715041

RESUMO

Protoporphyrinogen oxidase (PPO, EC 1.3.3.4) is a significant target for the discovery of novel bleaching herbicides. Starting from the active fragments of several known commercial herbicides, a series of PPO inhibitors with diphenyl ether scaffolds were designed and synthesized by substructure splicing and bioisosterism methods. The greenhouse herbicidal activity and the PPO inhibitory activity in vitro were measured. The results showed that the novel synthesized compounds have good PPO inhibitory activity, and the IC50 value against corn PPO ranges from 0.032 ± 0.008 mg/L to 3.245 ± 0.247 mg/L. Among all target compounds, compound P2 showed the best herbicidal activity, with a half inhibitory concentration (IC50) of 0.032 ± 0.008 mg/L. In addition, the molecular docking results showed that the benzene ring part of compound P2 can form a π-π stacking with PHE-392, and the trifluoromethyl group and ARG-98 form two hydrogen bonds. Crop safety experiments and cumulative concentration analysis experiments indicated that compound P2 can be used for weed control in rice, wheat, soybean and corn. Therefore, compound P2 can be selected to develop potential lead compounds for novel PPO inhibitors.


Assuntos
Inibidores Enzimáticos , Herbicidas , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Herbicidas/química , Herbicidas/farmacologia , Simulação de Acoplamento Molecular , Protoporfirinogênio Oxidase , Relação Estrutura-Atividade
13.
Mycopathologia ; 187(5-6): 547-565, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35931867

RESUMO

Pseudogymnoascus destructans (= Geomyces destructans) is a psychrophilic filamentous fungus that causes White-Nose Disease (WND; the disease associated with White-Nose Syndrome, WNS) in hibernating bats. The disease has caused considerable reductions in bat populations in the USA and Canada since 2006. Identification and detection of the pathogen in pure cultures and environmental samples is routinely based on qPCR or PCR after DNA isolation and purification. Rapid and specific direct detection of the fungus in the field would strongly improve prompt surveillance, and support control measures. Based on the genes coding for ATP citrate lyase1 (acl1) and the 28S-18S ribosomal RNA intergenic spacer (IGS) in P. destructans, two independent LAMP assays were developed for the rapid and sensitive diagnosis of the fungus. Both assays could discriminate P. destructans from 159 tested species of filamentous fungi and yeasts. Sensitivity of the assays was 2.1 picogram per reaction (pg/rxn) and 21 femtogram per reaction (fg/rxn) for the acl1 and IGS based assays, respectively. Moreover, both assays also work with spores and mycelia of P. destructans that are directly added to the master mix without prior DNA extraction. For field-diagnostics, we developed and tested a field-applicable version of the IGS-based LAMP assay. Lastly, we also developed a protocol for preparation of fungal spores and mycelia from swabs and tape liftings of contaminated surfaces or infected bats. This protocol in combination with the highly sensitive IGS-based LAMP-assay enabled sensitive detection of P. destructans from various sources.


Assuntos
Ascomicetos , Quirópteros , Doenças Nasais , Animais , Ascomicetos/genética , Reação em Cadeia da Polimerase em Tempo Real , Citratos , RNA Ribossômico 28S
14.
Biom J ; 64(5): 835-857, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35692062

RESUMO

Large agricultural field trials may display irregular spatial trends that cannot be fully captured by a purely randomization-based analysis. For this reason, paralleling the development of analysis-of-variance procedures for randomized field trials, there is a long history of spatial modeling for field trials, starting with the early work of Papadakis on nearest neighbor analysis, which can be cast in terms of first or second differences among neighboring plot values. This kind of spatial modeling is amenable to a natural extension using splines, as has been demonstrated in recent publications in the field. Here, we consider the P-spline framework, focusing on model options that are easy to implement in linear mixed model packages. Two examples serve to illustrate and evaluate the methods. A key conclusion is that first differences are rather competitive with second differences. A further key observation is that second differences require special attention regarding the representation of the null space of the smooth terms for spatial interaction, and that an unstructured variance-covariance structure is required to ensure invariance to translation and rotation of eigenvectors associated with that null space. We develop a strategy that permits fitting this model with ease, but the approach is more demanding than that needed for fitting models using first differences. Hence, even though in other areas, second differences are very commonly used in the application of P-splines, our conclusion is that with field trials, first differences have advantages for routine use.


Assuntos
Melhoramento Vegetal , Modelos Lineares , Análise Espacial
15.
J Environ Sci Health B ; 57(5): 339-349, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35362360

RESUMO

Field trials were conducted in Guangzhou, Nanning, and Nanjing in two consecutive years to evaluate the terminal residue levels and dissipation trend of pymetrozine and chlorpyrifos in rice ecosystem. Analyses were carried out by high-performance-liquid-chromatography for pymetrozine and gas-chromatography-mass-spectrometry for chlorpyrifos, achieved good linear relationship over range from 0.01 to 5.0 mg·kg-1 for both (r > 0.9998). Average recoveries were 86.0% to 106.0% for pymetrozine, and 79.7% to 102.3% for chlorpyrifos at the spiking levels of 0.01, 0.1 and 1.0 mg·kg-1. Half-lives of pymetrozine in paddy water, paddy soil and rice plant were 0.35-2.81, 2.69-6.95 and 1.22-3.70 days, while that of chlorpyrifos were 0.86-1.88, 3.09-6.86 and 0.58-2.84 days. Final residues of pymetrozine and chlorpyrifos in brown rice ranged from less than 0.6 to 26.0 µg·kg-1 and 14.3 to 191.6 µg·kg-1, respectively. It is recommended that 25% pymetrozine and chlorpyrifos suspension be sprayed twice at the intervals of 10 days with dosages ranging from 375 (maximum recommended dosage) to 562.5 g a.i.·ha-1 (1.5 times of the maximum recommended dosage). The rice can be harvested safely 15 days after the last application of pymetrozine and chlorpyrifos. The research results help ensures the safe application of pymetrozine and chlorpyrifos in rice ecosystem.


Assuntos
Clorpirifos , Oryza , Resíduos de Praguicidas , Clorpirifos/análise , Ecossistema , Oryza/química , Resíduos de Praguicidas/análise , Solo/química , Triazinas
16.
Plant J ; 104(6): 1535-1550, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33048399

RESUMO

Heat stress occurring at reproductive stages can result in significant and permanent damage to crop yields. However, previous genetic studies in understanding heat stress response and signaling were performed mostly on seedling and plants at early vegetative stages. Here we identify, using a developmentally defined, gain-of-function genetic screen with approximately 18 000 Arabidopsis thaliana activation-tagged lines, a mutant that maintained productive seed set post-severe heat stress during flowering. Genome walking indicated this phenotype was caused by the insertion of 35S enhancers adjacent to a nuclear localized transcription factor AtMYB68. Subsequent overexpression analysis confirmed that AtMYB68 was responsible for the reproductive heat tolerance of the mutant. Furthermore, these transgenic Arabidopsis plants exhibited enhanced abscisic acid sensitivity at and post-germination, reduced transpirational water loss during a drought treatment, and enhanced seed yield under combined heat and drought stress during flowering. Ectopic expression of AtMYB68 in Brassica napus driven either by 35S or by heat-inducible promoter recapitulated the enhanced reproductive heat stress and drought tolerance phenotypes observed in the transgenic Arabidopsis. The improvement to heat stress is likely due to enhanced pollen viability observed in the transgenic plants. More importantly, the transgenic canola showed significant yield advantages over the non-transgenic controls in multiple locations, multiple season field trials under various drought and heat stress conditions. Together these results suggest that AtMYB68 regulate plant stress tolerance at the most important yield determining stage of plant development, and is an effective target for crop yield protection under current global climate volatility.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/fisiologia , Fatores de Transcrição/fisiologia , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Brassica napus , Desidratação , Flores/crescimento & desenvolvimento , Mutação com Ganho de Função , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas , Reprodução , Termotolerância , Fatores de Transcrição/genética
17.
Mol Syst Biol ; 16(12): e9667, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33346944

RESUMO

Most of our current knowledge on plant molecular biology is based on experiments in controlled laboratory environments. However, translating this knowledge from the laboratory to the field is often not straightforward, in part because field growth conditions are very different from laboratory conditions. Here, we test a new experimental design to unravel the molecular wiring of plants and study gene-phenotype relationships directly in the field. We molecularly profiled a set of individual maize plants of the same inbred background grown in the same field and used the resulting data to predict the phenotypes of individual plants and the function of maize genes. We show that the field transcriptomes of individual plants contain as much information on maize gene function as traditional laboratory-generated transcriptomes of pooled plant samples subject to controlled perturbations. Moreover, we show that field-generated transcriptome and metabolome data can be used to quantitatively predict individual plant phenotypes. Our results show that profiling individual plants in the field is a promising experimental design that could help narrow the lab-field gap.


Assuntos
Genes de Plantas , Genômica , Zea mays/genética , Análise por Conglomerados , Análise de Dados , Bases de Dados Genéticas , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Metaboloma/genética , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Estresse Fisiológico/genética , Transcriptoma/genética , Zea mays/crescimento & desenvolvimento
18.
J Public Health (Oxf) ; 43(2): 405-412, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-31786612

RESUMO

BACKGROUND: Prevalence of overweight and obesity during childhood is still elevated in high-income countries. GiochiAMO is a health promotion program that uses knowledge-based education and games to teach healthy nutrition and physical activity among children (6-8 years old). METHODS: This study was a single arm field trial. Second and third grade classes of primary school attended an oral presentation about nutrition and physical activity and then were involved in three game sessions. Two multiple-choice questionnaires were administered at the beginning and at the end of the trail. The following scores were measured: nutrition behavior score (NTs), physical activity behavior score (PAs) and delta score (Ds). Wilcoxon, T-test and Mann Whitney were used to perform the univariate analysis. RESULTS: A total number of 74 and 76 children participated in the physical activity and nutrition interventions. NTs was 4.17 (SD: 2.23) before and 5.03 (SD: 2.79) after the intervention (P = 0.005). PAs was 27.4 (SD: 9.6) before and 30.5 (SD: 10.7) after the intervention (P = 0.003). No significant differences were obtained comparing males and females for all scores. Ds was 0.86 for nutrition and 3.1 for physical activity. Univariate analysis of Delta scores obtained no significant differences. CONCLUSIONS: The present results confirm the effectiveness of 'GiochiAMO' to change nutrition and physical activity behavior.


Assuntos
Exercício Físico , Promoção da Saúde , Criança , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Itália/epidemiologia , Masculino , Sobrepeso
19.
J Environ Manage ; 298: 113479, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34385113

RESUMO

A globally increased demand for fuels and environmental concerns regarding fossil sources call for sustainable alternatives. Fast pyrolysis is a promising approach for converting different types of biomass to renewable Fast Pyrolysis Bio-Oil (FPBO) that can be used for heating, power generation and mobility. Side-products emerging from the process include low calorific gases and charcoal. Both are further combusted to generate energy for the process. From the charcoal, the process leaves behind fly ashes (FAs) that contain macro- and micronutrients. In this regard, FPBO-FAs might present valuable soil fertilizers, but also bear the risk of soil heavy metal (HM) contamination. In this study, the risk and potential benefit of FPBO-FAs derived from three different biomass sources (bark, forest residue and Miscanthus sp.) as soil amendments was tested. Twice, in autumn 2017 and 2018, FPBO-FAs were applied to the field (500 kg ash ha-1 y-1) in a grassland experiment. Neither physico-chemical and microbiological soil properties nor plant yield were affected following FPBO-FAs application. Seasonal differences and changes from year to year, however, were evident, both for some soil and plant properties. The lack of effects on (i) plant yield, (ii) soil microbiological and physicochemical properties, (iii) heavy metal concentrations in soil and plant suggest that the product may safely be applied. The fact that these field-trial results are in discordance with previous greenhouse trials suggest, however, that long-term trials would be needed.


Assuntos
Pirólise , Poluentes do Solo , Biomassa , Cinza de Carvão , Óleos de Plantas , Polifenóis , Solo , Poluentes do Solo/análise
20.
Appl Environ Microbiol ; 86(11)2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32220845

RESUMO

Given the continued high prevalence of mosquito-transmitted diseases, there is a clear need to develop novel disease and vector control strategies. Biopesticides of microbial origin represent a promising source of new approaches to target disease-transmitting mosquito populations. Here, we describe the development and characterization of a novel mosquito biopesticide, derived from an air-dried, nonlive preparation of the bacterium Chromobacterium sp. Panama (family: Neisseriaceae). This preparation rapidly and effectively kills the larvae of prominent mosquito vectors, including the dengue and Zika vector Aedes aegypti and the human malaria vector Anopheles gambiae During semi-field trials in Puerto Rico, we observed high efficacy of the biopesticide against field-derived A. aegypti populations, and against A. aegypti and Culex species larvae in natural breeding water, indicating the suitability of the biopesticide for use under more natural conditions. In addition to high efficacy, the nonlive Csp_P biopesticide has a low effective dose, a long shelf life, and high heat stability and can be incorporated into attractive larval baits, all of which are desirable characteristics for a biopesticide.IMPORTANCE We have developed a novel preparation to kill mosquitoes from an abundant soil bacterium, Chromobacterium sp. Panama. This preparation is an air-dried powder containing no live bacteria, and it can be incorporated into an attractive bait and fed directly to mosquito larvae. We demonstrate that the preparation has broad spectrum activity against the larval form of the mosquitoes responsible for the transmission of malaria and the dengue, chikungunya, yellow fever, West Nile, and Zika viruses, as well as mosquito larvae that are already resistant to commonly used mosquitocidal chemicals. Our preparation possesses many favorable traits: it kills at a low dosage, and it does not lose activity when exposed to high temperatures, all of which suggest that this preparation could eventually become an effective new tool for controlling mosquitoes and the diseases they spread.


Assuntos
Aedes/efeitos dos fármacos , Anopheles/efeitos dos fármacos , Agentes de Controle Biológico/farmacologia , Chromobacterium/química , Culex/efeitos dos fármacos , Inseticidas/farmacologia , Aedes/genética , Animais , Anopheles/genética , Culex/genética , Larva/efeitos dos fármacos , Larva/genética , Porto Rico
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