Changes in the nutritional value of rice grown under two projected climate change scenarios: elevated CO2 and elevated CO2 + elevated temperature.

info:eu-repo/semantics/publishedVersio

Evaluation of the potential of agro-industrial waste-based composts to control Botrytis gray mold and soilborne fungal diseases in lettuce

Composts are widely used in horticulture as organic amendments to improve the properties of soils. Composts have also been reported to enhance the disease suppressive potential of soils and, therefore, could be used as a strategy for managing plant diseases. The aim of this study was to test the ability of soils amended with four different agro-industrial waste-based composts (chestnut peels and shells, spent coffee grounds, grape marc, and olive leaves) to inhibit the growth and activity of Botrytis cinerea and several soilborne pathogens. First, the capacity of aqueous compost extracts to inhibit the growth of Botrytis cinerea and five soilborne fungi was evaluated in vitro using a broth macrodilution method. Second, lettuce plants were grown on soils amended with composts and inoculated either with B. cinerea or the soilborne fungus Fusarium oxysporum Schlechtendahl isolated from lamb’s lettuce. The determination of minimal inhibitory concentrations indicated that none of the composts inhibited the mycelium growth of the selected fungal pathogens. However, the pathogens did not cause any damage on plants grown on the chestnut- and olive-based composts. Lettuce yields were also highest for plants grown with composts made from chestnut and olive, irrespective of the amount of compost incorporated into soils (5% or 10%, weight basis). The grape-based compost also exhibited a fertilization effect, although the effect was associated with increased Fusarium wilt severity. Both N immobilization and symbiosis with the compost’s microflora were used to explain the pathogenicity of F. oxysporum Schlechtendahl in response to amendment with composts made from grape and coffee wastes. The beneficial effects of the chestnut- and olive-based composts reported in this study could be exploited in strategies aimed at reducing reliance on synthetic pesticides for the control of fungi in lettuce cultivation.This work was supported by European Investment Funds (FEDER/COMPETE/POCIOperational Competitiveness and Internationalization Program) under the project POCI-0145-FEDER006958 and by national funds provided by FCT—Portuguese Foundation for Science and Technology, under the projects PTDC/AGR-AAM/102006/2008, SFRH/BD/81473/2011 and UIDB/04033/2020

A Lipidomic Analysis of Leaves of Esca-Affected Grapevine Suggests a Role for Galactolipids in the Defense Response and Appearance of Foliar Symptoms

Both qualitative and quantitative changes occur in the lipid composition of Vitis vinifera L. tissues, which may compromise the defense response against Esca complex disease, a widespread and damaging trunk disease. In this study, a lipidomic analysis of grapevine leaves is conducted to assess how lipid membrane remodeling relates to the emergence and progression of Esca foliar symptoms. In total, 208 molecular species (including lipids, four hormones, and some other compounds of the metabolism of lipids) were detected. Lipid species were readily assigned to the classes fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, sterols, and prenol lipids. Using different clustering analyses, distinct metabolic pathways stimulated at different stages of disease development were characterized. These analyses revealed consistent changes in the abundance of 13 galactolipids and two diacylglycerolipids. Overall, the observations indicated an increment in the levels of these lipid species in leaves of asymptomatic vines and a progressive drop with increasing foliar symptom severity in symptomatic vines. Five fatty acids also appear to exert a central role in the etiopathogenesis of Esca complex disease because of their accumulation in leaves of asymptomatic vines, namely, heptadecanoic, linoleic, γ-linolenic, arachidonic, and stearic acids. Symptomatic leaves were characterized by high levels of all lipid classes, except for galactolipids, lyso-galactolipids, and compounds relevant to the biosynthesis of chlorophylls and carotenoids, that exhibited decreased levels. The data also suggested a jasmonic acid-associated signaling mechanism activation upon the invasion of woods by Esca-associated fungi, compared with abscisic and salicylic acids. Further research is required for validation of these results with additional molecular analyses using more vine cultivars

Metabolites Differentiating Asymptomatic and Symptomatic Grapevine Plants (Vitis vinifera ‘Malvasia-Fina’) Infected with Esca Complex Disease-Associated Fungi

Pathogens are known to affect major physiological processes in plants including the regulation of metabolic networks to maintain homeostasis. Metabolomic analyses generate large datasets that could be analyzed to give insight into the specific metabolic adaptations involved in plant responses to grapevine trunk diseases such as esca complex. The goals of this study were to identify metabolites differentiating asymptomatic and symptomatic grapevine plants infected with esca complex disease-associated fungi, and biosynthetic pathways active during disease progression. Experiments were performed using healthy, asymptomatic and symptomatic leaves of Vitis vinifera L. ‘Malvasia-fina’ naturally infected in the vineyard. A global metabolite profile of the samples was obtained using a UPLC + GC-MS/MS2 analytical platform. A total of 513 metabolites belonging to 60 pathways were detected. The analysis of the data allowed the elucidation of some of the mechanisms by which grapevine tolerate the presence of pathogens, and the selection of top metabolites worthy of further investigation

Exhibition of Local but Not Systemic Induced Phenolic Defenses in Vitis vinifera L. Affected by Brown Wood Streaking, Grapevine Leaf Stripe, and Apoplexy (Esca Complex)

Balance between constitutive and induced responses provides plants flexibility to cope with biotic stresses. This study tested the hypothesis that invasion of grapevine wood by esca-associated fungi induces the production of defensive compounds as part of locally- and systemically-induced responses. In a vineyard, different symptomatic expressions of “Esca complex” in Vitis vinifera L. ‘Malvasia’ were evaluated in annual inspections. Then, levels of phenolics and fatty acids were determined in asymptomatic leaves of brown wood streaking (BWS) and grapevine leaf stripe (GLSD) vines, and in symptomatic leaves of GLSD and apoplectic vines; the results were compared with levels in healthy vines. In asymptomatic leaves of BWS and some GLSD vines, levels of phenolics decreased, independent of the total phenolic group. Such responses were usually associated with an increase in levels of linoleic, γ-linolenic and arachidonic acids, well-known signal transduction mediators. In symptomatic leaves, levels of phenolics increased, which is consistent with a locally-induced response; the onset of symptoms coincided with the highest increases e.g., 35% for quercetin-3-O-glucuronide. Thus, the long latency period between trunk invasion by fungi and visible foliar damage and the year-to-year fluctuation in symptomatic expressions observed with “Esca complex” might be partially attributed to a better utilization of constitutive defenses

Decrease in rice aroma after application of growth regulators

Aromatic rices (Oryza sativa L.) compared to the leading varieties are low-yielding, susceptible to lodging and prone to attack by a number of insect pests and diseases. Under these conditions, various agricultural chemicals such as fertilizers, pesticides and growth regulators have been used for their cultivation. Few investigations, however, have examined the influence of these chemicals on rice aroma and flavor. In this study, changes in rice aroma after treatment with gibberellic acid, paclobutrazol, 3-indole acetic acid, and a regulator mixture consisting of paclobutrazol, proline and zinc chloride were for the first time examined using two aromatic rice cultivars. Applications were carried out after 25% of panicles had emerged. We studied 12 odor-active compounds, extracted and identified using static headspace coupled with gas chromatography. At the concentrations tested, all treatments with growth regulators resulted in reduced aroma content that affected overall flavor. In a smelling evaluation, control samples were significantly higher in intensity than treated samples. The difference between the aromas of control and treated samples was largely related to 2-acetyl-1-pyrroline, the major rice aroma compound, and lipid oxidation volatiles. For instance, in the cultivar Guixiangzhan grown during the late season, gibberellic acid treatment decreased the content of 2-acetyl-1-pyrroline by 19%, 3-indole acetic acid by 9%, paclobutrazol by 22%, and the regulator mixture by 21% compared with the control. Similar trends were observed in the Peizaruanxiang cultivar, with decreases ranging from 10 to 24%. Our findings demonstrate that treatments with growth regulators inhibited the metabolic processes associated with the formation of volatile compounds

Distribution of antioxidant compounds in the grain of the Mediterranean rice variety ‘Ariete’

<div><p>This work aimed at investigating the potential of the rice grain and its milling fractions (from clay and sandy soils) as sources of antioxidant compounds. Ten phenolic acids and four flavonoids were identified in their free and bound forms and were found to be mainly associated with the bran and the husk. On a whole grain basis, ferulic and <i>p</i>-coumaric acids accounted for 72% and 20% of total phenolic acids, respectively. The contents of the chemopreventive flavonoid tricin in the husk, bran, brown rice and white rice were 384.00, 39.71, 7.36 and 0.50 mg/kg, respectively. Eight vitamin E isomers, γ-oryzanol and phytic acid were also identified, and their distribution in the rice grain was recorded in the following decreasing order: bran, brown rice, white rice and husk. Overall, these results showed that the bran and husk of rice were rich sources of antioxidant compounds, revealing the potential multipurpose use of the rice grain parts.</p></div

Effect of lignocellulosic and phenolic compounds on ammonia, nitric oxide and greenhouse gas emissions during composting

Composting is recognised a promising technology for recycling and adding value to agro-food wastes. There are, however, potential environmental risks associated with composting, such as the emission of greenhouse gases (GHGs). The aim of this study was to quantify the emissions of carbon dioxide, methane, nitrous oxide, nitric oxide and ammonia during composting of five agro-food wastes originated from the broccoli, chestnut, olive and grape industries, and to study the relationship between the emissions and the lignin, cellulose, hemicellulose and phenolic contents of the wastes. According to physicochemical indicators monitored during the process, all agro-food residues tested were suitable for composting, with chestnut in the top and broccoli in the bottom of the range. Composting of chestnut and olive led to higher carbon dioxide, methane and nitrous oxide emissions, whereas lower emissions were observed with white grape. A positive correlation was found between phenolics and nitric oxide (r = 0.63; p < 0.01), but not with the other gases. Lignocellulose showed a positive correlation with nitrous oxide (r = 0.51; p < 0.05), but not with carbon dioxide and methane. The accumulation of lignin was highest in the chestnut compost, which was associated with lower nitric oxide and ammonia emissions relative to the other waste materials. The results show that wastes with high lignocellulose can be managed using composting with additional benefits on the environment in relation to mitigating nitrogen losses.info:eu-repo/semantics/publishedVersio

Application of Compost and Biochar Mixtures to Soils to Produce Parsley Plants Rich in Nutrients and Antioxidant Compounds

Composts and biochar individually or in combination have been used for decades for improving soil quality and health. To date, very few studies have focused on the quality of food produced using compost-biochar mixtures. In this study, the use of biochar to improve the fertilization effect of composts and the quality of greenhouse-grown parsley was investigated by adding biochar to composts made from a mixture of broiler chicken wastes and sugar bagasse, sawdust, urban trees, napier grass, or cotton residues. On average, highest N and P contents were obtained with the bagasse- and sawdust-biochar substrates. The tree-biochar substrate led to increased levels of phenolic compounds in parsley compared to all the other organic substrates

Application of NaCl Plant Extracts to Decrease the Costs of Microfiltration for Winery Wastewater Treatment

The present study aimed, for the first time, to evaluate the production and application of NaCl plant extracts in a coagulation&ndash;flocculation&ndash;decantation process (CFD process) for the optimization of the microfiltration process (MF process) for the treatment of winery wastewater (WW). To evaluate the efficiency of the NaCl extracts, aluminum sulfate (10%) was applied as a comparison. The CFD process was optimized by varying the WW pH, coagulant dosage, agitation, type and dosage of flocculants before the microfiltration process. The application of Chelidonium majus L. (seeds) achieved 29.7, 99.7 and 95.3% total organic carbon, turbidity and total suspended solids removal, respectively, with 108 mg of filter consumption. In conclusion, NaCl plant extracts are a promising technology for WW treatment