scholarly journals Exploratory and discriminant analysis of plant phenolic profiles obtained by UV–vis scanning spectroscopy

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Monique Souza ◽  
Jucinei José Comin ◽  
Rodolfo Moresco ◽  
Marcelo Maraschin ◽  
Claudinei Kurtz ◽  
...  
Keyword(s):  
Discriminant Analysis ◽  
Cover Crops ◽  
Weed Management ◽  
Principal Component ◽  
R Package ◽  
Supervised Machine Learning ◽  
Change Analysis ◽  
Fast Analysis ◽  
Allelopathic Potential ◽  
Phenolic Profiles

Abstract Some species of cover crops produce phenolic compounds with allelopathic potential. The use of math, statistical and computational tools to analyze data obtained with spectrophotometry can assist in the chemical profile discrimination to choose which species and cultivation are the best for weed management purposes. The aim of this study was to perform exploratory and discriminant analysis using R package specmine on the phenolic profile of Secale cereale L., Avena strigosa L. and Raphanus sativus L. shoots obtained by UV–vis scanning spectrophotometry. Plants were collected at 60, 80 and 100 days after sowing and at 15 and 30 days after rolling in experiment in Brazil. Exploratory and discriminant analysis, namely principal component analysis, hierarchical clustering analysis, t-test, fold-change, analysis of variance and supervised machine learning analysis were performed. Results showed a stronger tendency to cluster phenolic profiles according to plant species rather than crop management system, period of sampling or plant phenologic stage. PCA analysis showed a strong distinction of S. cereale L. and A. strigosa L. 30 days after rolling. Due to the fast analysis and friendly use, the R package specmine can be recommended as a supporting tool to exploratory and discriminatory analysis of multivariate data.

scholarly journals Cover Crops for Weed Management in Southern Reduced-Tillage Vegetable Cropping Systems

2013 ◽  
Vol 27 (1) ◽  
pp. 212-217 ◽  
Author(s):  
Andrew J. Price ◽  
Jason. K. Norsworthy
Keyword(s):  
Cover Crops ◽  
Weed Management ◽  
Cover Crop ◽  
Agricultural Land ◽  
Organic Production ◽  
Reduced Tillage ◽  
Management Options ◽  
Allelopathic Potential ◽  
Systems Research ◽  
Future Production

With growing agricultural demands from both conventional and organic systems comes the need for sustainable practices to ensure long-term productivity. Implementation of reduced- or no-till practices offers a number of environmental benefits for agricultural land and maintains adequate yield for current and future production. Concerns over satisfactory pest control options, particularly weed control, have contributed to the slow adoption of conservation practices in many areas. To identify effective alternative weed management options for use in conservation systems, research in the Southeast has continued to evaluate the use of cover crops in conjunction with reduced-tillage practices. A number of cover crop species, including cereal grains, legumes, and Brassicaceae species, that have potential to suppress weeds through direct crop interference or allelopathic potential have been investigated. Many recent research projects in the Midsouth and southeastern United States have assessed the success of cover crops in reduced-tillage row crop settings with promising outcomes in some systems. However, continued research is necessary to identify appropriate cover crop and tillage systems for use in other agricultural settings, such as vegetable crops and organic production systems.

scholarly journals Methods of preparing aqueous extract and bioactivity of Mentha spicata L. on Raphanus sativus L. seeds

Acta Iguazu ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 118-130
Author(s):  
Leonardo Pereira Xavier ◽  
Andrea Pires ◽  
Lisandro Tomas da Silva Bonome ◽  
Gabriela Silva Moura ◽  
Gilmar Franzener ◽  
...  
Keyword(s):  
Phenolic Compounds ◽  
Aqueous Extract ◽  
Cover Crops ◽  
Weed Management ◽  
Raphanus Sativus ◽  
Extraction Methods ◽  
Mentha Spicata ◽  
Allelopathic Potential ◽  
Raphanus Sativus L ◽  
Physiological Quality

The plant interaction knowledge can be applied in several sectors in agriculture such as crop rotation, weed management, green manure and the use of cover crops. Studies on the allelopathic potential of certain plants have been carried out with the application of vegetable extracts on the seeds of a sensitive plant, however, a consensus has not been reached regarding the best way to prepare such extracts. This study aimed to evaluate the efficacy of methods of extraction of allelopathic compounds and the bioactivity of different concentrations of the Mentha spicata L. aqueous extract on Raphanus sativus L. seeds. A completely randomized design was used in a 5x4 factorial scheme with four replications and four extraction methods (infusion, grinding in a blender, drying at 40 °C and 70 °C) and five concentrations (0; 25; 50; 75 and 100%). The variables investigated were: phenolic compounds quantification, germination, germination speed index (GSI), mean germination time (MGT), radish shoot and root length. The extract presenting the highest amount of phenolic compounds was prepared via infusion (724.36 µg/mL), followed by drying at 40 °C (605.07 µg/mL), blending (594.12 µg/mL) and drying at 70 °C (529.36 µg/mL). The Mentha spicata L. aqueous extracts interfered in the radish seed physiological quality, by inhibiting germination, GSI and MGT increase, mainly when in higher concentrations. There was a directly proportional relation between the quantity of phenolic compounds extracted through different extraction methods and the interference in the physiological quality of the radish seeds.

scholarly journals Allelopathy of Cover Crops on the Germination and Initial Development of Euphorbia heterophylla

2019 ◽  
Vol 11 (14) ◽  
pp. 74 ◽  
Author(s):  
Alexandre Bianchini ◽  
Pedro Valério Dutra de Moraes ◽  
Juliana Domanski Jakubski ◽  
Cristiana Bernardi Rankrape ◽  
Elyoenay Gadyel ◽  
...  
Keyword(s):  
Cover Crops ◽  
Weed Management ◽  
Cover Crop ◽  
Aerial Part ◽  
Chenopodium Quinoa ◽  
Aqueous Extracts ◽  
Germination Test ◽  
Initial Development ◽  
Allelopathic Potential ◽  
Avena Strigosa

Cover crop is a important way for weed management in agriculture. The objective of this study was to investigate the effects of aqueous extracts of the aerial part of Avena strigosa, Cichorium intybus, Chenopodium quinoa and Fagopyrum esculentum in different concentrations on the germination and development of Euphorbia heterophylla. The experimental design was completely randomized, in factorial 4 × 5 with four replicates. Factor A-aqueous extracts of the aerial part of the cover plants and factor B-concentrations of 0%; 1%, 2.5%, 5% and 10%. A total of 25 E. heterophylla seeds, arranged in gerboxes, were used and 15 ml of the extracts were added according to the treatments. The germination test was performed in a growth chamber (BOD) with photoperiod of 12/12 light/dark hours and constant temperature of 25±1 °C. The data were submitted to analysis of variance by the F test, a comparison was made between means and the concentration factor of the extracts and the regression analysis. The C. quinoa aqueous extracts (10%) presented greater allelopathic potential than the other extracts in the variables tested for E. heterophylla. C. intybus presented allelophatic potential with results superior to A. strigosa and F. esculentum. The C. quinoa and C. intybus extracts have allelopathic potential when compared to the control with the highest dose (10%), interfering mainly in the root portion of E. heterophylla.

scholarly journals Identification of Tentative Traceability Markers with Direct Implications in Polyphenol Fingerprinting of Red Wines: Application of LC-MS and Chemometrics Methods

Separations ◽  
2021 ◽  
Vol 8 (12) ◽  
pp. 233
Author(s):  
Laurentiu Mihai Palade ◽  
Constantin Croitoru ◽  
Camelia Albu ◽  
Gabriel Lucian Radu ◽  
Mona Elena Popa
Keyword(s):  
Discriminant Analysis ◽  
High Performance ◽  
Red Wine ◽  
Storage Period ◽  
Principal Component ◽  
Data Matrix ◽  
Red Wines ◽  
Liquid Chromatography Mass Spectrometry ◽  
Phenolic Profiles ◽  
Stage 1

This study investigated the potential of using the changes in polyphenol composition of red wine to enable a more comprehensive chemometric differentiation and suitable identification of authentication markers. Based on high performance liquid chromatography-mass spectrometry (HPLC-MS) data collected from Feteasca Neagra, Merlot, and Cabernet Sauvignon finished wines, phenolic profiles of relevant classes were investigated immediately after vinification (Stage 1), after three months (Stage 2) and six months (Stage 3) of storage, respectively. The data were subjected to multivariate analysis, and resulted in an initial vintage differentiation by principal component analysis (PCA), and variety grouping by canonical discriminant analysis (CDA). Based on polyphenol common biosynthesis route and on the PCA correlation matrix, additional descriptors were investigated. We observed that the inclusion of specific compositional ratios into the data matrix allowed for improved sample differentiation. We obtained simultaneous discrimination according to the considered oenological factors (variety, vintage, and geographical origin) as well as the respective clustering applied during the storage period. Subsequently, further discriminatory investigations to assign wine samples to their corresponding classes relied on partial least squares-discriminant analysis (PLS-DA); the classification models confirmed the clustering initially obtained by PCA. The benefits of the presented fingerprinting approach might justify its selection and warrant its potential as an applicable tool with improved authentication capabilities in red wines.

scholarly journals Allelopathic Potential of Phenolic Compounds in Secale Cereale Cultivars and Its Relationship with Seeding Density

2019 ◽  
Vol 9 (15) ◽  
pp. 3072
Author(s):  
Bimal Kumar Ghimire ◽  
Chang Yeon Yu ◽  
Balkrishna Ghimire ◽  
Eun Soo Seong ◽  
Ill Min Chung
Keyword(s):  
Phenolic Compounds ◽  
Cover Crops ◽  
Secale Cereale ◽  
Chenopodium Album ◽  
Principal Component ◽  
Syringic Acid ◽  
Seeding Density ◽  
Allelopathic Effect ◽  
Allelopathic Potential

In this study, we investigated the allelopathic effect of Secale cereale cultivars on different weeds that grow in the cultivated fields of Perilla frutescens. Two S. cereale cultivars, Paldong and Singhi, were used to test the allelopathic effect on in vitro grown Digitaria ciliaris, Chenopodium album, Amaranthus lividus, Portulaca oleracea, Pinellia ternata and Commelina communis. The results indicated that S. cereale extracts affect callus growth of weeds in terms of fresh weight and percentage of growth inhibition. The inhibitory effects of both S. cereale cultivars combined with grass cover extracts were higher than using grass weeds alone. Concentrations of all identified phenolic compounds were significantly higher in the leaves extracts of Paldong compared to Singhi. Particularly, syringic acid in leaves extract of the Paldong cultivar were 12.87-fold higher than in the Singhi cultivar. The other predominant phenolic compounds such as salicylic acid, p-coumaric acid, vanillic acid, and p-hydroxybenzoic acids were 3.30, 4.63, 3.11, and 1.28 times higher, respectively, in the leaves extracts of Paldong compared to Singhi. Principal component analysis (PCA) results indicated that the composition of phenolic compounds was significantly related to cultivar types and plant parts used. In addition, biomass increase caused increased weed inhibitory capacity of S. cereale both in tillage and no-tillage regimes. These results suggest that the biomass of cover crops negatively influenced weed density.

scholarly journals Effect of Weed Management on the Parasitoid Community in Mediterranean Vineyards

Biology ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 7
Author(s):  
Gabriella Möller ◽  
Tamar Keasar ◽  
Idan Shapira ◽  
Daniella Möller ◽  
Marco Ferrante ◽  
...  
Keyword(s):  
Cover Crops ◽  
Weed Management ◽  
Soil Conservation ◽  
Management Practices ◽  
Ground Cover ◽  
Parasitoid Species ◽  
Parasitoid Community ◽  
Growing Seasons ◽  
Conservation Biocontrol ◽  
Suction Sampling

Enriching agroecosystems with non-crop vegetation is a popular strategy for conservation biocontrol. In vineyards, the effects of specific seeded or planted cover crops on natural enemies are well-studied, whereas conserving spontaneously developing weeds received less attention. We compared parasitoid communities between matched pairs of vineyard plots in northern Israel, differing in weed management practices: “herbicide”, repeated herbicide applications vs. “ground cover”, maintaining resident weeds and trimming them when needed. Using suction sampling, we assessed the parasitoids’ abundance, richness, and composition during three grape-growing seasons. Ground cover plots had greater parasitoid abundances and cumulative species richness than herbicide-treated plots, possibly because of their higher vegetation cover and richness. Dominant parasitoid species varied in their magnitude and direction of response to weed management. Their responses seem to combine tracking of host distributions with attraction to additional vegetation-provided resources. Parasitoid community composition was mildly yet significantly influenced by weed management, while season, year, and habitat (weeds vs. vine) had stronger effects. Vineyard weeds thus support local biocontrol agents and provide additional previously demonstrated benefits (e.g., soil conservation, lower agrochemical exposure) but might also attract some crop pests. When the benefits outweigh this risk, weed conservation seems a promising step towards more sustainable agricultural management.

scholarly journals Spring-planted cover crops for weed control in soybean

2021 ◽  
pp. 1-8
Author(s):  
Katja Koehler-Cole ◽  
Christopher A. Proctor ◽  
Roger W. Elmore ◽  
David A. Wedin
Keyword(s):  
Weed Control ◽  
Biomass Production ◽  
Cover Crops ◽  
Weed Management ◽  
Block Design ◽  
Weed Suppression ◽  
Crop Species ◽  
Cold Temperatures ◽  
Weed Biomass ◽  
Small Grains

Abstract Replacing tillage with cover crops (CC) for weed management in corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] systems with mechanical weed control has many soil health benefits but in the western Corn Belt, CC establishment after harvest is hampered by cold temperatures, limited labor and few compatible CC species. Spring-planted CC may be an alternative, but information is lacking on suitable CC species. Our objective was to evaluate four spring-planted CC with respect to biomass production and weed suppression, concurrent with CC growth and post-termination. Cover crop species tested were oat (Avena sativa L.), barley (Hordeum vulgare L.), brown mustard [Brassica juncea (L.) Czern.] and yellow mustard (Brassica hirta Moench). They were compared to no-CC treatments that were either tilled pre- and post-planting of soybean (no-CC tilled) or not tilled at all (no-CC weedy). CC were planted in late March to early April, terminated 52–59 days later using an undercutter, and soybean was planted within a week. The experiment had a randomized complete block design with four replications and was repeated for 3 years. Mustards and small grains produced similar amounts of biomass (1.54 Mg ha−1) but mustard biomass production was more consistent (0.85–2.72 Mg ha−1) than that of the small grains (0.35–3.81 Mg ha−1). Relative to the no-CC weedy treatment, mustards suppressed concurrent weed biomass in two out of 3 years, by 31–97%, and small grains suppressed concurrent weed biomass in only 1 year, by 98%. Six weeks after soybean planting, small grains suppressed weed biomass in one out of 3 years, by 79% relative to the no-CC weedy treatment, but mustards did not provide significant weed suppression. The no-CC tilled treatment suppressed weeds each year relative to the no-CC weedy treatment, on average 87%. The ineffective weed control by CC reduced soybean biomass by about 50% six weeks after planting. While spring-planted CC have the potential for pre-plant weed control, they do not provide adequate early season weed suppression for soybean.

Labile carbon and other soil quality indicators in two tillage systems during transition to organic agriculture

2011 ◽  
Vol 26 (4) ◽  
pp. 342-353 ◽  
Author(s):  
David Bruce Lewis ◽  
Jason P. Kaye ◽  
Randa Jabbour ◽  
Mary E. Barbercheck
Keyword(s):  
Soil Quality ◽  
Cover Crops ◽  
Organic Agriculture ◽  
Weed Management ◽  
Cover Crop ◽  
Transition Period ◽  
Interactive Effects ◽  
Labile Carbon ◽  
Initial Field ◽  
Soil Attributes

AbstractWeed management is one of the primary challenges for producers transitioning from conventional to organic agriculture. Tillage and the use of cover crops are two weed control tactics available to farmers transitioning to organic management, but little is known about their interactive effects on soil quality during the transition period. We investigated the response of soils to tillage and initial cover crop during the 3-year transition to organic in a cover crop–soybean (Glycine max)–maize (Zea mays) rotation in the Mid-Atlantic region of the USA. The tillage treatment contrasted full, inversion tillage with moldboard plowing (FT) versus reduced tillage with chisel plowing (RT). The cover crop treatment contrasted annual versus mostly perennial species during the first year of the rotation. The experiment was initiated twice (Start 1 and Start 2), in consecutive years in adjacent fields. By the end of the experiment, labile carbon, electrical conductivity, pH and soil moisture were all greater under RT than under FT in both starts. Soil organic matter and several other soil attributes were greater under RT than under FT in Start 1, but not in Start 2, perhaps owing to differences between starts in initial field conditions and realized weather. Soil attributes did not differ between the two cover crop treatments. Combining our soils results with agronomic and economic analyses on these plots suggests that using RT during the organic transition can increase soil quality without compromising yield and profitability.

scholarly journals A fast and low-cost approach to quality control of alcohol-based hand sanitizer using portable near infrared spectrometer and chemometrics

2021 ◽  
pp. 096703352098731
Author(s):  
Adenilton C da Silva ◽  
Lívia PD Ribeiro ◽  
Ruth MB Vidal ◽  
Wladiana O Matos ◽  
Gisele S Lopes
Keyword(s):  
Quality Control ◽  
Discriminant Analysis ◽  
Near Infrared ◽  
Nir Spectroscopy ◽  
Principal Component ◽  
Partial Least Square ◽  
Least Square ◽  
Chemical Components ◽  
Linear Discriminant ◽  
Hand Sanitizer

The use of alcohol-based hand sanitizers is recommended as one of several strategies to minimize contamination and spread of the COVID-19 disease. Current reports suggest that the virucidal potential of ethanol occurs at concentrations close to 70%. Traditional methods of verifying the ethanol concentration in such products invite potential errors due to the viscosity of chemical components or may be prohibitively expensive to undertake in large demand. Near infrared (NIR) spectroscopy and chemometrics have already been used for the determination of ethanol in other matrices and present an alternative fast and reliable approach to quality control of alcohol-based hand sanitizers. In this study, a portable NIR spectrometer combined with classification chemometric tools, i.e., partial least square discriminant analysis (PLS–DA) and linear discriminant analysis with successive algorithm projection (SPA–LDA) were used to construct models to identify conforming and non-conforming commercial and laboratory synthesized hand sanitizer samples. Principal component analysis (PCA) was applied in an exploratory data study. Three principal components accounted for 99% of data variance and demonstrate clustering of conforming and non-conforming samples. The PLS–DA and SPA–LDA classification models presented 77 and 100% of accuracy in cross/internal validation respectively and 100% of accuracy in the classification of test samples. A total of 43% commercial samples evaluated using the PLS–DA and SPA–LDA presented ethanol content non-conforming for hand sanitizer gel. These results indicate that use of NIR spectroscopy and chemometrics is a promising strategy, yielding a method that is fast, portable, and reliable for discrimination of alcohol-based hand sanitizers with respect to conforming and non-conforming ethanol concentrations.

Identification and Quantification of Metamizole in Traditional Herbal Medicines using Spectroscopy FTIR-ATR combined with Chemometrics

2021 ◽  
pp. 4413-4419
Author(s):  
Dharmastuti Cahya Fatmarahmi ◽  
Ratna Asmah Susidarti ◽  
Respati Tri Swasono ◽  
Abdul Rohman
Keyword(s):  
Discriminant Analysis ◽  
Herbal Medicine ◽  
Ftir Spectroscopy ◽  
Herbal Medicines ◽  
Principal Component ◽  
Attenuated Total Reflection ◽  
Partial Least Square ◽  
Least Square ◽  
Partial Least Square Regression ◽  
Precision Data

The study aims to develop an effective, efficient, and reliable method using Fourier Transform Infrared (FTIR) spectroscopy with Attenuated Total Reflection (ATR) combined with chemometric for identifying the synthetic drug in Indonesian herbal medicine known as Jamu. Jamu powders, Metamizole, and the binary mixture of Jamu and Metamizole were measured using FTIR-ATR at the mid-infrared region (4000-650 cm-1). The obtained spectra profiles were further analyzed by Principal Component Analysis, Partial Least Square Regression, Principal Component Regression, and Discriminant Analysis. Jamu Pegel Linu (JPL), Jamu Encok (JE), Jamu Sakit Pinggang (JSP), Metamizole (M), and adulterated Jamu by Metamizole were discriminated well on PCA score plot. PLSR and PCR showed the accuracy and precision data to quantify JPL, JE, and JSP, and each adulterated by M with R2 value > 0,995 and low value of RMSEC and RMSEP. Discriminant Analysis (DA) was successfully grouping Jamu and Metamizole without any misclassification. A combination of FTIR spectroscopy and chemometrics offered useful tools for detecting Metamizole in traditional herbal medicine.

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