Organic vs conventional production of peppermint, lemon balm, and lavender; effect on yields and oil composition

Organic production and markets are expanding rapidly. A field study was conducted to compare effects of organic (OS) and conventional (CS) production systems and unfertilized control on peppermint (Mentha x piperita L.), lemon balm (Melissa officinalis L.), and lavender (Lavandula angustifolia Mill.) productivity and oil profile. In peppermint, both production systems provided greater yields than the yields in the unfertilized control. The application of vermicompost at 20 t/ha increased peppermint fresh biomass and essential oil yields with 20-31% and 24-28%, respectively, compared with the control. However, peppermint herbage and essential oil yields under OS were 7-87% and 13-54%, respectively, lower compared with the respective yields under CS. Overall, peppermint under OS had slightly higher essential oil content compared to the control; however, the oil composition was not significantly different from that in the CS. In lemon balm, fresh herbage yields in the OS were increased by 12-70% relative to the unfertilized control. However, compared with the yields at CS plots, yields in the OS were satisfactory only during the first year. In the second year, fresh herbage yields in the OS were up to 70% lower compared with those from the CS. The production system did not have a significant effect on the lemon balm oil content and composition. In lavender, the OS included two applications of probiotic product on six lavender genotypes. During the first year, CS lavender had 6 to 13% greater essential oil yield compared with the organically grown ones. In the second year, CS grown lavender out yielded OS grown by 9 to 24% in the case of inflorescence and 13 to 24% in the case of essential oil. However, during the third year of the study, the yields of inflorescences from OS stabilized and almost equaled those from CS. Overall, organic production of peppermint, lemon balm, and lavender may result in lower yields in the first 2-3 years, however, the essential oil content and composition may not be affected. Depending on the price premiums for organically produced herbage and essential oil, organically produced peppermint, lemon balm, and lavender may be economically and agronomically viable after the initial couple of years

Organic vs conventional production of peppermint, lemon balm, and lavender; effect on yields and oil composition

Organic production and markets are expanding rapidly. A field study was conducted to compare effects of organic (OS) and conventional (CS) production systems and unfertilized control on peppermint (Mentha x piperita L.), lemon balm (Melissa officinalis L.), and lavender (Lavandula angustifolia Mill.) productivity and oil profile. In peppermint, both production systems provided greater yields than the yields in the unfertilized control. The application of vermicompost at 20 t/ha increased peppermint fresh biomass and essential oil yields with 20-31% and 24-28%, respectively, compared with the control. However, peppermint herbage and essential oil yields under OS were 7-87% and 13-54%, respectively, lower compared with the respective yields under CS. Overall, peppermint under OS had slightly higher essential oil content compared to the control; however, the oil composition was not significantly different from that in the CS. In lemon balm, fresh herbage yields in the OS were increased by 12-70% relative to the unfertilized control. However, compared with the yields at CS plots, yields in the OS were satisfactory only during the first year. In the second year, fresh herbage yields in the OS were up to 70% lower compared with those from the CS. The production system did not have a significant effect on the lemon balm oil content and composition. In lavender, the OS included two applications of probiotic product on six lavender genotypes. During the first year, CS lavender had 6 to 13% greater essential oil yield compared with the organically grown ones. In the second year, CS grown lavender out yielded OS grown by 9 to 24% in the case of inflorescence and 13 to 24% in the case of essential oil. However, during the third year of the study, the yields of inflorescences from OS stabilized and almost equaled those from CS. Overall, organic production of peppermint, lemon balm, and lavender may result in lower yields in the first 2-3 years, however, the essential oil content and composition may not be affected. Depending on the price premiums for organically produced herbage and essential oil, organically produced peppermint, lemon balm, and lavender may be economically and agronomically viable after the initial couple of years

Micronutrient Concentrations in Soil and Wheat Decline by Long-Term Tillage and Winter Wheat–Pea Rotation

Tillage plays a major role in nutrient dynamics under dryland cropping systems, but there remains uncertainty regarding the long-term impacts of tillage on nutrient availability. The objective of this study was to examine the influence of tillage intensity and timing on micronutrient concentration of soils and winter wheat (Triticum aestivum L.) under dryland winter wheat–pea (Pisum sativum L.) or WW-P rotation. The treatments included moldboard tillage in fall (FT) and spring (ST), disk/chisel tillage (DT), and no-tillage (NT). The concentrations of Mehlich III extractable boron, manganese, zinc, copper, and iron in soil were unaffected by the tillage methods; however, a significant decline in extractable zinc in the top 10 cm soil was observed compared to an adjacent undisturbed grass pasture (GP) (NT: 2.3 mg kg−1 vs. GP: 6.0 mg kg−1). In the upper 10 cm soil surface, NT (123 mg kg−1) maintained the extractable manganese concentration with GP (175 mg kg−1) whereas FT (97 mg kg−1), ST (92 mg kg−1), and DT (113 mg kg−1) had lower manganese than GP. Soil pH declined in the upper 10 cm under NT more than in the rest of the WW-P treatments. The results suggest NT can play a vital role in sustaining micronutrient availability due to decreased soil pH and the greater amount of organic matter within the surface soil of NT compared to other tillage method

Utilization of nutmeg (Myristica fragrans Houtt.) seed hydrodistillation time to produce essential oil fractions with varied compositions and pharmacological effects

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. The intent of this study was to utilize distillation timeframes (DT) of nutmeg (Myristica fragrans) essential oil (EO) to generate fractions with differential chemical compositions and bioactivity. Ten fractions were captured at the following distillation timeframes: 0.0–0.5, 0.5–1.0, 1.0–2.5, 2.5–5.0, 5.0–10, 10–30, 30–60, 60–90, 90–120, and 120–240 min. In addition, a control EO was collected from a straight 0–240 min non-stop distillation. ANOVA and advanced regression modeling revealed that the produced EO fractions possess substantial variation in the concentration of potentially desired compounds. The concentrations (%) of α-phellandrene, 3-carene, p-cymene, limonene, α-thujene, α-pinene, camphene, sabinene, β-pinene, and myrcene decreased, while the concentrations (%) of α-terpinene, γ-terpinene, terpinolene, and myristicin increased in later DT fractions. Nutmeg EO showed some antimalarial activity against Plasmodium falciparum D6, but did not exhibit significant antifungal activity. In general, nutmeg seed oil yields increased with an increase of DT. These results may be utilized by industries using nutmeg EO

Macronutrients in Soil and Wheat as Affected by a Long-Term Tillage and Nitrogen Fertilization in Winter Wheat-Fallow Rotation

The insights gained from the long-term impacts of tillage and N fertilization on soil fertility are crucial for the development of sustainable cropping systems. The objectives of this study were to quantify the effects of 75 years of tillage and N fertilization on macronutrients in soil and wheat (Triticum aestivum L.) tissues grown in a winter wheat–summer fallow rotation. The experiment included three types of tillage (disc, DP; sweep, SW; and moldboard, MP) and five N application rates (0, 45, 90, 135, and 180 kg ha−1). Soil and tissue samples were analyzed for the concentration of total N, S, and C, Mehlich III extractable P, K, Mg, Ca in the soil, and the total concentration of the same nutrients in wheat tissue. Soil N concentration was significantly greater under DP (1.10 g kg−1) than under MP (1.03 g kg−1). The P concentration in upper 20 cm soil depth increased with increased N rates. Comparison of experiment plots to a nearby undisturbed pasture revealed a decline of P (32%), SOC (34%), Mg (77%), and Ca (86%) in the top 10 cm soil depth. The results suggest that DP with high N rates could reduce the macronutrient decline in soil and plant over time

Essential Oil Yield and Composition of the Balkan Endemic Satureja pilosa Velen. (Lamiaceae)

© 2020 by the authors. Satureja pilosa Velen. senso lato is a Balkan endemic plant that is not well characterized and is found on rocky outcrops of limestone base in Stara Planina (the Balkan Mountains) and the Rhodope Mountains. The objective of this study was to assess the variability of essential oil (EO) content and composition of S. pilosa collected at 33 locations across the Balkan and Rhodope Mountains in Bulgaria using advanced statistical methods including cluster analysis. The EO content in dried aboveground biomass varied from 0.52% to 2.03%. More than 21 EO constituents were identified, belonging to the groups of monoterpenes and sesquiterpenes. The monoterpenes were the predominant class, comprising 84.8% to 96.1% of the total EO. Thymol and carvacrol were the major constituents of the phenolic monoterpenoids. Thymol varied from 36.6% to 67.1% and carvacrol varied from 52.4% to 93.0% of the total oil. p‐Cymene also varied widely, from 9.6%–34.0%. There were significant variations between locations and within a location in the EO content and composition. This study identified several chemotypes: (1) thymol and p‐cymene; (2) thymol, p-cymene and γ‐terpinene; (3) carvacrol and p‐cymene; (4) carvacrol, p‐cymene and γ‐terpinene; and (5) carvacrol. This is the first comprehensive study on the endemic plant S. pilosa that identified several chemotypes based on the EO composition. The S. pilosa EO from the five different chemotypes exhibited larvicidal and mosquito repellent activity against Aedes aegypti. The identified chemotypes can be utilized for the development of new varieties with desirable compositions to meet specific industry needs and new mosquito management control products

Essential Oil Yield, Composition, and Bioactivity of Sagebrush Species in the Bighorn Mountains

Sagebrush (Artemisia spp.) are dominant wild plants in large areas of the U.S., Canada and Mexico, and they include several species and subspecies. The aim was to determine if there are significant differences in essential oil (EO) yield, composition, and biological activity of sagebrush within the Bighorn Mountains, U.S. The EO yield in fresh herbage varied from 0.15 to 1.69% for all species, including 0.25–1.69% in A. tridentata var. vaseyana, 0.64–1.44% in A. tridentata var. tridentata, 1% in A. tridentata var. wyomingensis, 0.8–1.2% in A. longifolia, 0.8–1% in A. cana, and 0.16% in A. ludoviciana. There was significant variability in the EO profile between species, and subspecies. Some EO constituents, such as α-pinene (0–35.5%), camphene (0–21.5%), eucalyptol (0–30.8%), and camphor (0–45.5%), were found in most species and varied with species and subspecies. The antioxidant capacity of the EOs varied between the species and subspecies. None of the sagebrush EOs had significant antimicrobial, antimalarial, antileishmanial activity, or contained podophyllotoxin. Some accessions yielded EO with significant concentrations of compounds including camphor, eucalyptol, cis-thujone, α-pinene, α-necrodol-acetate, fragranol, grandisol, para-cymene, and arthole. Therefore, chemotypes can be selected and possibly introduced into culture and be grown for commercial production of these compounds to meet specific industry needs

Grinding and Fractionation during Distillation Alter Hemp Essential Oil Profile and Its Antimicrobial Activity

The hypothesis of this study was that we can modify the essential oil (EO) profile of hemp (Cannabis sativaL.) and obtain fractions with differential composition and antimicrobial activity. Therefore, the objective was to evaluate the effects of grinding of hemp biomass before EO extraction and fractionation during distillation on EO profile and antimicrobial activity. The study generated a several EO fractions with a diversity of chemical profile and antimicrobial activity. The highest concentrations of beta-pinene and myrcene in the EO can be obtained in the 5-10 min distillation time (DT) of ground material or in the 80-120 min DT of nonground material. High delta-3-carene and limonene EO can be obtained from 0-5 min DT fraction of nonground material. High eucalyptol EO can be sampled either in the 0-5 min DT of the ground material or in the 80-120 min of nonground material. Overall, the highest concentrations of beta-caryophyllene,alpha-(E)-bergamotene, (Z)-beta-farnesene,alpha-humulene, caryophyllenyl alcohol, germacrene D-4-ol, spathulenol, caryophyllene oxide, humulene epoxide 2,beta-bisabolol,alpha-bisabolol, sesquiterpenes, and cannabidiol (CBD) can be obtained when EO is sampled in the 80-120 min DT and the material is nonground. Monoterpenes in the hemp EO can be increased twofold to 85% by grinding the material prior to distillation and collecting the EO in the first 10 min. However, grinding resulted in a slight but significant decrease in the CBD concentration of the EO. CBD-rich oil can be produced by collecting at 120-180 min DT. Different EO fractions had differential antimicrobial activity. The highest antimicrobial activity of EO fraction was found againstStaphylococcus aureussubsp.aureus. THC-free EO can be obtained if the EO distillation is limited to 120 min. The results can be utilized by the hemp processing industry and by companies developing new hemp EO-infused products, including perfumery, cosmetics, dietary supplements, food, and pharmaceutical industries

Micronutrients in the Soil and Wheat: Impact of 84 Years of Organic or Synthetic Fertilization and Crop Residue Management

Crop residues are an important source of plant nutrients. However, information on the various methods of residue management on micronutrients in soil and wheat (Triticum aestivum L.) over time is limited. A long-term (84-year) agroecosystem experiment was assessed to determine the impact of fertilizer type and methods of crop residue management on micronutrients over time under dryland winter wheat-fallow rotation. The treatments were: no N application with residue burning in fall (FB), spring (SB), and no residue burn (NB); 45 kg N ha−1 with SB and NB; 90 kg N ha−1 with SB and NB; pea vines; and farmyard manure (FYM) and a nearby undisturbed grass pasture (GP). Wheat grain, straw, and soil samples from 1995, 2005, and 2015 were used to determine tissue total and soil Mehlich III extractable Mn, Cu, B, Fe, and Zn, and soil pH. After 84 years, extractable Mn and B in the top 10 cm of soil decreased in all plots, except for B in FYM and SB. The FYM plots had the highest extractable Mn (114 mg kg−1) in the top 10 cm soil; however, it declined by 33% compared to the GP (171 mg kg−1). Extractable Zn in the top 10 cm of soil increased with FYM while it decreased with inorganic N application in 2015; however, total Zn in grain increased by 7% with inorganic N (90 kg ha−1) application compared to FYM application. The results suggest that residue management had similar impact on soil micronutrients. Inorganic N and FYM application can be integrated to reduce micronutrient losses from cultivatio

Chemical Characterization and Antibacterial Activity of Essential Oil of Medicinal Plants from Eastern Serbia

The objective of this study was to evaluate wild growing Satureja kitaibelii, Thymus serpyllum, Origanum vulgare, Achillea millefolium and Achillea clypeolata with respect to their essential oil (EO) content, composition and antimicrobial activity. The five species were collected at Mt. Rtanj and the village of Sesalac, Eastern Serbia. The main EO constituents of Lamiaceae plants were p-cymene (24.4%), geraniol (63.4%) and germacrene D (21.5%) in Satureja kitaibelii, Thymus serpyllum and Origanum vulgare ssp. vulgare, respectively. A. millefolium EO had multiple constituents with major ones being camphor (9.8%), caryophyllene oxide (6.5%), terpinen-4-ol (6.3%) and 1,8-cineole (5.6%), while the main EO constituents of A. clypeolata were 1,8-cineole (45.1%) and camphor (18.2%). Antimicrobial testing of the EO showed that Staphylococcus aureus (Gram-positive) was more sensitive to all of the tested EOs than Escherichia coli (Gram-negative). S. kitaibelii EO showed the highest antimicrobial activity against both tested bacterial strains. This is the first study to characterize the EO composition and antimicrobial activity of these five medicinal species from Eastern Serbia in comparison with comprehensive literature data. The results can be utilized by the perfumery, cosmetics, food and pharmaceutical industries, but also for healing purposes in self-medication