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Gating in grapevine: Relationship between application of the fungicide fludioxonil and circadian rhythm on photosynthesis Texte intégral
2009
Petit, Anne-Noëlle | Fontaine, Florence | Clement, Christophe | Vaillant-Gaveau, Nathalie
The aim of this study was to determine the impact of the fludioxonil (fdx) fungicide on the diurnal fluctuation in grapevine photosynthesis. Therefore, fdx treatment was performed at the end of flowering, at 8 am, 12 am or 7 pm. The study was performed in experimental field and several photosynthesis parameters were followed one day after treatment. Morning fdx treatment induced (i) a significant and simultaneous drop of both photosynthesis (Pn) and stomatal conductance between 8 am and 4 pm and (ii) an increase of intercellular CO2 concentration when compared to control plants. On the contrary, evening fdx treatment did not affect Pn whereas midday treatment caused Pn increase after 4 pm. These data suggest that (i) morning fdx treatment results in a non-stomatal limitation of Pn, (ii) midday treatment is more suitable to treat grapevine with fdx and (iii) a phenomenon of gating was noticed. The period of fdx spraying was an important parameter in stress response: the midday fdx treatment is more suitable to treat grapevine with fdx.
Afficher plus [+] Moins [-]Cumulative risk assessment of dietary exposure to triazole fungicides from 13 daily-consumed foods in China Texte intégral
2021
Cui, Kai | Wu, Xiaohu | Zhang, Ying | Cao, Junli | Wei, Dongmei | Xu, Jun | Dong, Fengshou | Liu, Xingang | Zheng, Yongquan
The agroeconomic benefits of the routine use of triazole fungicides on crops have been evident for more than 40 years. However, increasing evidence shows that residues of triazoles are ubiquitous in various foods and thus could pose a potential health risk to humans. We analyzed 3406 samples of 13 food commodities that were collected from markets in 9 regions across China, and assessed the health risk of both chronic and acute exposure to the triazoles for Chinese children (1–6 years old) and the general population. Among all samples, 55.52% had triazoles in concentrations of 0.10–803.30 μg/kg, and 29.77% of samples contained a combination of 2–7 triazoles. Tebuconazole and difenoconazole were the most commonly found triazoles in the foods, being detected in 33.44% and 30.45% of samples, respectively. Chronic and acute cumulative risk assessment for total triazoles based on a relative potency factor method revealed that exposure to triazoles from these particular commodities was below the levels that might pose a health risk (chronic hazard index range, 5.90×10⁻⁷ to 1.83×10⁻³; acute hazard index range, 7.77×10⁻⁵ to 0.39, below 1). Notably, dietary exposure risk for children was greater than that for the general population—particularly for the acute intake of mandarin, grape, and cucumber (acute hazard index values of 0.35–0.39). Despite the low health risk, the potential hazards of exposure to triazoles should raise public concern owing to their ubiquitous presence in common foods and potential cumulative effects.
Afficher plus [+] Moins [-]Multi-omics analyses on the response mechanisms of ‘Shine Muscat’ grapevine to low degree of excess copper stress (Low-ECS) Texte intégral
2021
Chen, Mengxia | Fang, Xiang | Wang, Zicheng | Shangguan, Lingfei | Liu, Tianhua | Chen, Chun | Liu, Zhongjie | Ge, Mengqing | Zhang, Chuan | Zheng, Ting | Fang, Jinggui
Copper stress is one of the most severe heavy metal stresses in plants. Grapevine has a relatively higher copper tolerance than other fruit crops. However, there are no reports regarding the tolerance mechanisms of the ‘Shine Muscat’ (‘SM’) grape to a low degree of excess copper stress (Low-ECS). Based on the physiological indicators and multi-omics (transcriptome, proteome, metabolome, and microRNAome) data, 8 h (h) after copper treatment was the most severe stress time point. Nonetheless, copper stress was alleviated 64 h after treatment. Cu ion transportation, photosynthesis pathway, antioxidant system, hormone metabolism, and autophagy were the primary response systems in ‘SM’ grapevine under Low-ECS. Numerous genes and proteins, such as HMA5, ABC transporters, PMM, GME, DHAR, MDHAR, ARGs, and ARPs, played essential roles in the ‘SM’ grapevine's response to Low-ECS. This work was carried out to gain insights into the multi-omics responses of ‘SM’ grapevine to Low-ECS. This study provides genetic and agronomic information that will guide better vinery management and breeding copper-resistant grape cultivars.
Afficher plus [+] Moins [-]Relation between organophosphate pesticide metabolite concentrations with pesticide exposures, socio-economic factors and lifestyles: A cross-sectional study among school boys in the rural Western Cape, South Africa Texte intégral
2021
Molomo, Regina Ntsubise | Basera, Wisdom | Chetty-Mhlanga, Shala | Fuhrimann, Samuel | Mugari, Mufaro | Wiesner, Lubbe | Röösli, Martin | Dalvie, Mohamed Aqiel
Evidence on the relationship between lifestyle, socio-economic factors and pesticide exposure and urinary concentrations of organophosphate (OP) pesticide metabolites among children is generally incomplete. This study investigated the relationship between socio-economic factors and reported pesticide exposures and the sum of three urinary concentrations of dialkyl phosphate metabolites (DAP) among boys living in the rural areas of the Western Cape, South Africa. Data was collected during a cross-sectional study of 183 boys from three agricultural intense areas. Measurements included a questionnaire on socio-economic and pesticide exposures and urinary DAP concentrations. Most boys (70%) lived on farms with a median age of 12 years (range: 5.0–19.5 years). Children aged >14 years had lower DAP urine concentrations (median = 39.9 ng/ml; β = −68.1 ng/ml; 95% CI: −136.8, 0.6) than children aged 9 years and younger (median = 107.0 ng/ml). DAP concentrations also varied significantly with area, with concentrations in the grape farming area, Hex River Valley (median = 61.8 ng/ml; β = −52.1; 95% CI: −97.9, −6.3 ng/ml) and the wheat farming area, Piketberg (median = 72.4 ng/ml; β = −54.2; 95% CI: 98.8, −9.7 ng/ml) lower than those in the pome farming area, Grabouw (median = 79.9 ng/ml). Other weaker and non-significant associations with increased DAP levels were found with increased household income, member of household working with pesticides, living on a farm, drinking water from an open water source and eating crops from the vineyard and or garden. The study found younger age and living in and around apple and grape farms to be associated with increased urinary DAP concentrations. Additionally, there were other pesticide exposures and socio-economic and lifestyle factors that were weakly associated with elevated urinary DAP levels requiring further study. The study provided more evidence on factors associated to urinary DAP concentrations especially in developing country settings.
Afficher plus [+] Moins [-]Comparison of different stomatal conductance algorithms for ozone flux modelling Texte intégral
2007
Büker, P. | Emberson, L.D. | Ashmore, M.R. | Cambridge, H.M. | Jacobs, C.M.J. | Massman, W.J. | Müller, J. | Nikolov, N. | Novak, K. | Oksanen, E.
Comparison of different stomatal conductance algorithms for ozone flux modelling Texte intégral
2007
Büker, P. | Emberson, L.D. | Ashmore, M.R. | Cambridge, H.M. | Jacobs, C.M.J. | Massman, W.J. | Müller, J. | Nikolov, N. | Novak, K. | Oksanen, E.
A multiplicative and a semi-mechanistic, BWB-type [Ball, J.T., Woodrow, I.E., Berry, J.A., 1987. A model predicting stomatal conductance and its contribution to the control of photosynthesis under different environmental conditions. In: Biggens, J. (Ed.), Progress in Photosynthesis Research, vol. IV. Martinus Nijhoff, Dordrecht, pp. 221-224.] algorithm for calculating stomatal conductance (gs) at the leaf level have been parameterised for two crop and two tree species to test their use in regional scale ozone deposition modelling. The algorithms were tested against measured, site-specific data for durum wheat, grapevine, beech and birch of different European provenances. A direct comparison of both algorithms showed a similar performance in predicting hourly means and daily time-courses of gs, whereas the multiplicative algorithm outperformed the BWB-type algorithm in modelling seasonal time-courses due to the inclusion of a phenology function. The re-parameterisation of the algorithms for local conditions in order to validate ozone deposition modelling on a European scale reveals the higher input requirements of the BWB-type algorithm as compared to the multiplicative algorithm because of the need of the former to model net photosynthesis (An).
Afficher plus [+] Moins [-]Comparison of different stomatal conductance algorithms for ozone flux modelling
Insight into how fertilization strategies increase quality of grape (Kyoho) and shift microbial community Texte intégral
2022
Li, Xunan | Chu, Changbin | Ding, Sheng | Wei, Huawei | Wu, Shuhang | Xie, Bing
Organic and bioorganic fertilizers were increasingly used for agricultural soil. However, little is known on what kind of organic fertilizer application strategies can promote grape production well and how appropriate fertilization strategies improve soil properties and shift microbial community. This study investigated the improvement in soil physicochemical properties as well as their relations with microbial community structure and grape quality under different fertilization strategies. Our results found that (bio)organic fertilizer (CF1, CF2, and BF) especially combined application of organic and bioorganic fertilization (CBF) had smaller effects on electrical conductivity (EC) and pH, while it improved soil nutrients including N, P, K, and organic matter (OM) well, thereby promoting the grape quality comparing to the group without any fertilizer (CK) and with chemical fertilizer (NPK). Especially, the concentrations of Cr, Hg, Zn, and Cu were reduced by 13.63%, 12.50%, 12.52%, and 11.75% in CBF, respectively. Additionally, CF1, CF2, and BF, especially CBF, optimized the communities’ composition and increased the abundance of some plant probiotics such as Solirubrobacter and Lysobacter. Nevertheless, excessive application of organic fertilizer derived from livestock manure could cause the accumulation of heavy metals such as Zn and Cu in soil and leaves, which could further influence the grape quality. Additionally, the structure of microbial communities was also changed possibly because some bacterial genera showed distinct adaptability to the stress of heavy metals or the utilization capacity of N, P, K, and OM. Our results demonstrated that combined application of organic and bioorganic fertilization showed a great influence on soil physicochemical properties, whose positive changes could further optimize microbial communities and facilitate the promotion of grape quality.
Afficher plus [+] Moins [-]Investigation of long-term hazards of chemical weapon agents in the environment of Sardasht area, Iran Texte intégral
2022
Vaezihir, Abdorreza | Pirkhezranian, Asra | Sehati, Negar | Hosseinzadeh, Mohammad Reza | Salehi-Lisar, Seyed Yahya | Sanderson, Hans
The present study aimed to investigate the persistence and existence of chemical warfare agents (CWAs) and related dissipation products in the environment of Sardasht area, Iran. Three types of environmental samples including water, soil, and native local plant materials were collected and analyzed. Gas chromatography-mass spectrometry in the electron impact ionization mode has been developed for the separation, screening, identification, and qualification of chemicals after the sample preparation methods. The initial results revealed that no trace of related compounds or CWAs was detected in the soil and water samples. However, trace amounts of some degradation products of blistering agents like mustard gas (HD) and lewisite were found in a tree wood from a house subjected to chemical attack as well as in barley samples (a mixture of leaves and root) collected from an agricultural field in the area indicating chronic low exposure to the environment and people. In order to validate the applied extraction procedures, ethylene glycol was spiked to some of the samples including groundwater, surface soil, grape, and alfalfa plants. All the recoveries were in the range of 83.6–107.4% with the relative standard deviations varying from 4.9% to 12.4% (n = 3) successfully.
Afficher plus [+] Moins [-]Plant uptake and soil retention of radionuclides and metals in vineyard environments Texte intégral
2021
Gulan, Ljiljana | Stajic, Jelena M. | Milenkovic, Biljana | Zeremski, Tijana | Milić, Stanko | Krstic, Dragana
In most European countries, each adult citizen drinks on average more than 20 L of wine every year. Three popular wine-growing areas (Aleksandrovac, Topola, and Orahovac) in Serbia were studied in order to investigate the abundance and uptake of elements from vineyard soil to plants. The specific activities of radionuclides (²²⁶Ra, ²³²Th, ⁴⁰K, ¹³⁷Cs, and ⁷Be) were measured in soil, leaves, and grape berries. ²²⁶Ra and ²³²Th were positively correlated with silt and clay and negatively correlated with sand content in soil. Specific activities of natural radionuclides were also negatively correlated with soil pH and CaCO₃. Significant correlations of ⁴⁰K and ¹³⁷Cs with organic matter in soil were found. Concentrations of fifteen metals (As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn, Fe, K, Na, Ca, Mg, and Hg) were also measured in soil samples as well as in grapevine leaves. Analyzed soils were rich in Ni, Cu, Co, Cr, and Cd. High concentrations of Cu were probably caused by long-term use of Cu-based fungicides. Cu was correlated with Fe and organic matter content in soil. Soil-to-plant transfer factors (TF) were calculated to estimate the uptake of radionuclides and metals. Correlations obtained via PCA enable distinction between the sites Aleksandrovac and Topola relative to Orahovac. The first principal component (PC1) accounting for 30.70% of the total variance correlated significantly with soil pH (H₂O), contents of CaCO₃, Na, Ca, ⁴⁰K, and ²²⁶Ra in soil, as well as with ²²⁶Ra, Na, Ca in plants and TFCₐ. The second principal component (PC2), with total variance of 17.21%, was mainly correlated with variables pertaining to Mg, Co, and Cr in the soil and TFK.
Afficher plus [+] Moins [-]Microbiological and Chemical Modifications of Soil Cultivated with Grapevine Following Agronomic Application of Olive Mill Wastewater Texte intégral
2020
Lanza, B. | Di Serio, M.G. | Di Giovacchino, L.
The reuse of olive mill wastewater (OMW) by spreading on agricultural land is subject to a long-time debate since they supply to agricultural land both substances of undoubted positive influence on fertility and compounds that may adversely alter its chemical, physical and microbiological characteristics and/or cause negative effects on crops. In this study different amounts of OMW from 3-phases centrifugal decanter were spread in February on soil cultivated with grapevine in a research-farm located in central Italy for 11 consecutive years, with the aim to verify the long term effect on grape production, physico-chemical and microbiological characteristics of soil. In particular, the effect of the OMW spread in the largest amount (50 L m⁻²) was an increase of the weight of the grape-brunches and total grapes production and, in addition, an improvement of the soil characteristics due to the increase of the content of the organic reducing substances with humic-like properties. Moreover, it was also ascertained that in the short-medium period (2–8 months) the respiratory activity of the micro-organisms of the soil parcels, treated with different amount of OMW, was higher than that of the soil control parcels. The results obtained demonstrated that the controlled spreading of OMW helps to increase both the grapes crop and the fertility of the soil, recycling the organic matter and mineral nutrients, in this way allowing to reduce, or avoid, the use of chemical fertilisers.
Afficher plus [+] Moins [-]N2O, CO2, Production, and C Sequestration in Vineyards: a Review Texte intégral
2018
Nistor, Eleonora | Dobrei, Alina Georgeta | Dobrei, Alin | Camen, Dorin | Sala, Florin | Prundeanu, Horia
Even if it is less polluting than other farm sectors, grape growing management has to adopt measures to mitigate greenhouse gas (GHG) emissions and to preserve the quality of grapevine by-products. In viticulture, by land and crop management, GHG emissions can be reduced through adjusting methods of tillage, fertilizing, harvesting, irrigation, vineyard maintenance, electricity, natural gas, and transport until wine marketing, etc. Besides CO₂, nitrous oxide (N₂O) and methane (CH₄), released from fertilizers and waste/wastewater management are produced in vineyards. As the main GHG in vineyards, N₂O can have the same harmful action like large quantities of CO₂. Carbon can be found in grape leaves, shoots, and even in fruit pulp, roots, canes, trunk, or soil organic matter. C sequestration in soil by using less tillage and tractor passing is one of the efficient methods to reduce GHG in vineyards, with the inconvenience that many years are needed for detectable changes. In the last decades, among other methods, cover crops have been used as one of the most efficient way to reduce GHG emissions and increase fertility in vineyards. Even if we analyze many references, there are still limited information on practical methods in reducing emissions of greenhouse gases in viticulture. The aim of the paper is to review the main GHG emissions produced in vineyards and the approached methods for their reduction, in order to maintain the quality of grapes and other by-products.
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