Bio-Herbicidal Effects of Oregano and Rosemary Essential Oils on Chamomile (Matricaria chamomilla L.) Crop in Organic Farming System

Prospects for using pesticides in agriculture

Concerns about food safety issues have put considerable pressure on pesticide producers in Europe and worldwide to reduce the levels of pesticide residues in food. The aim of this work is to assess the use of traditional pesticides and their effects, to present perspectives in this field and to identify regulatory needs for their use and implementation. The work is based on a systematic review in which the research problem was defined, primary sources were selected and critically appraised, data were collected, analysed and evaluated, and conclusions were formulated. The state of the pesticide market and the current legal requirements for risk assessment in relation to exposure to chemical substances were reviewed. Food safety issues are presented through the prism of pesticide residues in food. Their widespread use and considerable persistence have made them ubiquitous in the natural environment and their residues pose a threat to the environment and to human and animal health. It has been shown that the most important factor influencing the search for new tools to control diseases and pests of crops is the progressive development of resistance of these populations to currently used pesticides. Various alternatives to the phasing out of synthetic pesticides in the form of natural products are therefore being developed to support the development of the natural products market.

Biocontrol Potential of Essential Oils in Organic Horticulture Systems: From Farm to Fork

In recent decades, increasing attention has been paid to food safety and organic horticulture. Thus, people are looking for natural products to manage plant diseases, pests, and weeds. Essential oils (EOs) or EO-based products are potentially promising candidates for biocontrol agents due to their safe, bioactive, biodegradable, ecologically, and economically viable properties. Born of necessity or commercial interest to satisfy market demand for natural products, this emerging technology is highly anticipated, but its application has been limited without the benefit of a thorough analysis of the scientific evidence on efficacy, scope, and mechanism of action. This review covers the uses of EOs as broad-spectrum biocontrol agents in both preharvest and postharvest systems. The known functions of EOs in suppressing fungi, bacteria, viruses, pests, and weeds are briefly summarized. Related results and possible modes of action from recent research are listed. The weaknesses of applying EOs are also discussed, such as high volatility and low stability, low water solubility, strong influence on organoleptic properties, and phytotoxic effects. Therefore, EO formulations and methods of incorporation to enhance the strengths and compensate for the shortages are outlined. This review also concludes with research directions needed to better understand and fully evaluate EOs and provides an outlook on the prospects for future applications of EOs in organic horticulture production.

A Comprehensive Review on Biology, Genetic Improvement, Agro and Process Technology of German Chamomile (Matricaria chamomilla L.)

German chamomile (M. chamomilla) is recognized as a star herb due to its medicinal and aromatic properties. This plant is found across a wide range of climatic and soil conditions. Both the flower heads and blue essential oils of German chamomile possess several pharmacological properties of an anti-inflammatory, antimicrobial, antiseptic, antispasmodic and sedative, etc., nature, which makes it a highly sought after herb for use in many pharma and aroma industries. Chamomile tea, prepared from its flower heads, is also a well-known herbal tea for mind and body relaxation. Though it is a high-demand herb, farmers have not adopted this plant for large scale cultivation as a crop, which could improve their livelihood, due to the high cost in flower heads harvesting, loss in over mature and immature flower heads picking during harvesting, unavailability of varieties and agrotechnologies for machine harvesting, a lack of efficient process development of oil extraction and in the lack of improved stable varieties. There are many studies that have reported on the phytochemistry and pharmacological uses of chamomile, which further explore its importance in the medicine industry. Several studies are also present in the literature on its cultivation practices and plant ecology. However, studies on breeding behavior, genetic improvement, varietal development and mechanical harvesting are scarce in German chamomile. Hence, keeping in mind various aspects of farmers' and researchers' interest, earlier reports on taxonomy, floral biology, processing of oil extraction, active constituents, uses, agronomy, breeding challenges and opportunities in German chamomile are summarized in this review.

Phenol-rich alternatives for Rosa x damascena Mill. Efficient phytochemical profiling using different extraction methods and colorimetric assays

Damask rose is a well-established, abundant source of phytochemicals, as well as economically important essential oil—however, its cultivation is demanding and costly. In this paper, extracts from four raw plant materials—Salvia officinalis, Sambucus nigra, Matricaria chamomilla, Calendula officinalis, known to be rich in phenolic compounds, but also far easier to cultivate—were directly compared to those obtained from Rosa × damascena Mill. By combining diverse extraction methodologies (in a Soxhlet apparatus, ultrawave-assisted and microwave-assisted, using supercritical CO₂) and complementary in vitro assays (radical scavenging, iron reducing, Folin–Ciocalteau and Al³⁺ complexation), it was possible to conveniently approximate and compare the phytochemical portfolios of those diverse plants. By factoring in the crop yields of different species, economically important conclusions can be reached—with pot marigold (C. officinalis) seemingly the most viable substitute for damask rose as a source of phenolics. Fatty acid and microelement analyses were also performed, to further enrich the chemical profiles of plant extracts. The paper also aims to collate and redesign multiple colorimetric assays frequently used while studying plant extracts in vitro, but criticized for their lack of correlation to in vivo activity. We show that they remain a viable tool for direct comparison of extraction methodologies, while highlighting their shortcomings.

Effects of L-Theanine on Hepatic Ischemia-Reperfusion Injury in Rats

OBJECTIVES

The effects of L-theanine on hepatic microcirculation during hepatic ischemia-reperfusion injury have not yet been investigated. The aim of this study was to investigate the influence of L-theanine on hepatic ischemia-reperfusion injury in rats.

MATERIALS AND METHODS

Thirty-two male Sprague Dawley rats weighing 250 to 300 g were used. Rats were divided into 4 groups: sham + saline, sham + L-theanine, hepatic ischemia-reperfusion injury + saline, and hepatic ischemia-reperfusion injury + L-theanine. Hepatic ischemia-reperfusion injury in rats was induced by 60 minutes of 70% ischemia and 4 hours of reperfusion. The extent of hepatic cell injury, functional capillary density, hepatic functions, and changes in some enzyme markers in hepatic tissue were investigated in the 4 groups.

RESULTS

The induction of hepatic ischemia-reperfusion injury resulted in significant increases in hepatic necrosis; serum activity of alanine aminotransferase, lactate dehydrogenase, gamma-glutamyltransferase, and tumor necrosis factor alpha; tissue activity of inducible nitric oxide synthase, myeloperoxidase, and malondialdehyde, and oxide glutathione; and H score for hypoxia-inducible factor 1-alpha in the liver. In the liver, there were significant reductions in reduced glutathione, ratio of reduced glutathione-to-oxide glutathione, and functional capillary density. The use of L-theanine improved these changes.

CONCLUSIONS

L-theanine demonstrated protective effects on hepatic injury after ischemia-reperfusion injury in rats. However, new studies are needed to confirm the preventive or reducing effects of L-theanine on hepatic ischemia-reperfusion injury.

The Applicability of Essential Oils in Different Stages of Production of Animal-Based Foods

Essential oils (EOs) have been used for centuries, and interest in these compounds has been revived in recent years. Due to their unique chemical composition as well as antimicrobial, immunostimulatory, anti-inflammatory and antioxidant properties, EOs are used in pharmacology, cosmetology and, increasingly, in animal breeding and rearing, and processing of animal raw materials. Essential oils have become a natural alternative to preservatives, taste enhancers and, most importantly, antibiotics, because the European Union banned the use of antibiotics in metaphylaxis in animal husbandry in 2006. In the animal production chain, EOs are used mainly as feed additives to improve feed palatability and increase feed intake, improve animal resistance and health status, and to prevent and treat diseases. Recent research indicates that EOs can also be applied to sanitize poultry houses, and they can be used as biopesticides in organic farming. Essential oils effectively preserve meat and milk and, consequently, improve the safety, hygiene and quality of animal-based foods. Novel technologies such as encapsulation may increase the bioavailability of EOs and their application in the production of food and feed additives.

Essential oil characterization of Prunus spinosa L., Salvia officinalis L., Eucalyptus globulus L., Melissa officinalis L. and Mentha x piperita L. by a volatolomic approach

In this study a volatolomic approach is proposed for the characterization of the volatile organic compound (VOC) composition of essential oils (EOs) extracted from common aromatic plants. Five species (Prunus spinosa L., Salvia officinalis L., Eucalyptus globulus L., Melissa officinalis L. and Mentha x piperita L.), particularly widespread in Southern Italy, were selected as recognized sources of natural bioactive compounds with beneficial properties. Hydro distillation and solid-liquid extraction with ethanol at different percentages were used to obtain EOs, and their extraction capabilities were compared analyzing chromatographic profiles obtained by headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography - mass spectrometry (GC-MS). The analytical procedure was optimized in term of SPME fiber, adsorption time and desorption time. GC-MS analyses were performed allowing the profiling of the VOC fingerprint in each plant extract. Experimental data were processed by a statistical multivariate approach (Analysis of Variance and Principal Component Analysis obtained for compounds and chemical classes), confirming that EO aroma profiles were statistically different for each of the selected five plants. The proposed volatolomic approach has proved to be an easy and efficient tool to study the aroma profile, allowing the collection of specific information and opening new perspectives and opportunities for the detection and identification of VOCs in agricultural and ecological applications.

Acaricidal Efficacy of Jasmine and Lavender Essential Oil or Mustard Fixed Oil against Two-Spotted Spider Mite and Their Impact on Growth and Yield of Eggplants

Simple Summary

The two-spotted spider mite (TSSM) represents the highly polyphagous pest worldwide in protected and open field condition results in a serious economic yield loss (50-100%) in severe infestation conditions. The ecological crisis attributable to the extra-application of acaricides has been an issue of concern in modern decades. It is former to estimate that nearly 2.5 million tons of pesticides are utilized in agricultural production yearly and the global injury evoked by pesticides achieves $100 billion yearly. It is therefore hoped that natural oils can offer alternative options to synthesis acaricides and contribute to pesticide resistance. Application of essential oils of lavender and jasmine, as well as mustard fixed oil, is inducing the plant resistance to TSSM as well as and improving plant growth and yield of eggplants

Abstract

Eggplant is repeatedly attacked by numerous pests, particularly two-spotted spider mite (TSSM), which considerably decline plant productivity. Synthetic acaricides are frequently applied for controlling TSSM, resulting in environmental pollution. The utilization of rational novel substances which repel or prevent TSSM establishment represents a sustainable eco-friendly to reduce the utilization of agrochemicals. A greenhouse investigation was done for assessing the bio-acaricidal activity of mustard (Brassica juncea L.) fixed oil (MFO), jasmine (Jasminum grandiflorum L.) essential oil (JEO), or lavender (Lavandula angustifolia L.) essential oil (LEO), and their influences on eggplant growth and productivity. The results demonstrated that JEO represents the most acaricidal properties against TSSM followed by MFO and/or LEO compared to control. Spraying with natural oils significantly improved eggplant growth, i.e., plant height, number of leaves, and branches/plant, in addition to the leaf area and relative leaf dry mass of the 3rd–5th upper leaves. The JEO had the strongest positive effect compared with other oils or control. Additionally, Natural oils application significantly increased photosynthetic pigment, chlorophyll _a:b ratio, and nitrogen, phosphorus, potassium, ascorbic acid, and phenols. The application of oils increased yield and its quality. In this study, JEO (2.5 mL/l) is shown to be extremely promising for the progress of new eco-friendly acaricides, improving plant growth and increasing eggplant yield.

Essential Oils as Potential Alternative Biocontrol Products against Plant Pathogens and Weeds: A Review

Naturally produced by aromatic plants, essential oils (EO) contain a wide range of volatile molecules, including mostly secondary metabolites, which possess several biological activities. Essential oils properties such as antioxidant, antimicrobial and anti-inflammatory activities are known for a long time and hence widely used in traditional medicines, cosmetics and food industries. However, despite their effects against many phytopathogenic fungi, oomycetes and bacteria as well as weeds, their use in agriculture remains surprisingly scarce. The purpose of the present review is to gather and discuss up-to-date biological activities of EO against weeds, plant pathogenic fungi, oomycetes and bacteria, reported in the scientific literature. Innovative methods, potentially valuable to improve the efficiency and reliability of EO, have been investigated. In particular, their use towards a more sustainable agriculture has been discussed, aiming at encouraging the use of alternative products to substitute synthetic pesticides to control weeds and plant diseases, without significantly affecting crop yields. An overview of the market and the recent advances on the regulation of these products as well as future challenges to promote their development and wider use in disease management programs is described. Because of several recent reviews on EO insecticidal properties, this topic is not covered in the present review.

Assessment of Factors Constraining Organic Farming Expansion in Lis Valley, Portugal

Organic farming can play an important role in rural development and food production, by reinforcing the trend toward sustainable agriculture and its purpose of ecosystem conservation. The agribusiness of organic farming is particularly relevant in family farming, given the labor availability and the short marketing circuits. The innovative techniques of organic farming, namely with soil fertility, weed and pest control, opens a wide range of possibilities in its development and extension. The expectation of organic farming profitability in small-scale family farming, supported by known successful examples, were the theme of a field study on Lis Valley Irrigation District to assess the constraints to its expansion in order to outline the procedures for the acquisition of technical knowledge, the adaptation of technologies, the support for the conversion of production models, and the specialized training of farmers for action. Results revealed that the: (i) farmer’s land structure, (ii) their mature age, (iii) low education level, and (iv) markets, are the main constrains for organic farming development. Furthermore, other uncertainties were identified, namely: (i) the certification process, (ii) the knowledge of new technologies, especially of crop protection, and (iii) the marketing problems to guaranteeing profitability. This study concludes that organic farming has significant potential for development in the Lis Valley and that the efforts and resources of the various stakeholders, namely the state, need to be harmonized to deliver effective support to farmers to promote organic farming that prioritizes: (i) rural development policies, (ii) supporting land restructuring, (iii) modernization of irrigation, (iv) stimulation of young farmers, (v) conversion and implementation of innovative technologies, (vi) the organization of farmers for better productive efficiency, and (vii) to facilitate market access.

Control of Erigeron bonariensis with Thymbra capitata, Mentha piperita, Eucalyptus camaldulensis, and Santolina chamaecyparissus Essential Oils

In the search of sustainable and environmentally friendly methods for weed control, there is increasing interest in essential oils (EOs) as an approach to reduce synthetic herbicide use. The phytotoxicity of Thymbra capitata, Mentha piperita, Eucalyptus camaldulensis, and Santolina chamaecyparissus EOs against the noxious weed Erigeron bonariensis were evaluated in pre- and post-emergence assays in greenhouse conditions. The EOs were applied at 2, 4, and 8 µL/mL, with Fitoil used as emulsifier. In post-emergence, two ways of application were tested, irrigation and spraying. Several germination parameters (germination %, mean germination time, and synchrony of the germination process) were evaluated in pre-emergence tests, and the phytotoxicity level was assessed in post-emergence. In pre-emergence, all EOs significantly reduced seed germination as compared to the controls, ranking: T. capitata > E. camaldulensis > S. chamaecyparissus > M. piperita. The effectiveness of all EOs varied with the tested dose, always following the rank 2 μL < 4 μL < 8 μL, with T. capitata EO showing full effectiveness even at the lowest dose. In post-emergence, T. capitata was the most effective EO, inducing a rather complete inhibition of plantlet growth at the highest two doses. These EOs demonstrated to have good potential for the formulation of natural herbicides.