Rainfed cultivation with supplemental irrigation modelling on seed yield and oil of Coriandrum sativum L. using precision agriculture and GIS moisture mapping

The aim of the present study was to determine the effects of rainfed and supplemental irrigation, and sowing period (SP) treatments on coriander (Coriandrum sativum L) yield, essential oil content and umbel heights by applying new agro-technologies (TDR-sensors for soil moisture (SM), geographical information system (GIS), precision agriculture, soil-hydraulic analyses and geostatistical models) for yield and SM root zone geospatial modelling and two-dimensional GIS mapping. Results of laboratory analysis indicated a suitable soil for coriander's growth and revealed that field's soil was characterized sandy clay loam (SCL) with mean values: soil organic matter (SOM) = 1.70%, bulk specific gravity = 1.42 g·cmr3, plant available water = 0.129 cm·cmr1, pH = 7.10 and cation-exchange capacity (CEC) = 19.3 cmol·kg-1. The two-way ANOVA statistical analysis (P = 0.05) results revealed that the irrigation treatments (IR1: rainfed, IR2: rainfed plus supplemental irrigation [best]), and the SP treatments (SP1: October's last week, SP2: November's first week [best]) significantly affects coriander's seed yield and essential oil content, but the SP have no significant effect on plant's umbel height (P = 0.873). Supplemental irrigation, using a limited amount of water, if applied during the critical crop growth stages, can result in substantial improvement on seed yield (+284.934%), essential oil content (+125.396%) and plant's umbel height (+117.929%). © 2021 IWA Publishing. All rights reserved

Lavender organic cultivation yield and essential oil can be improved by using bio-stimulants

Lavender is an aromatic-medicinal plant, cultivated in Greece and in Mediterranean basin in general. The aim of the current study was to investigate if the use of bio-stimulants could increase the yield of the flowering shoots and the essential oil content even from the establishment year. For the purposes of the study, in Microkastro Vojo Kozanis, lavender experimental field was established on November 2017 and the results refer to the experimentation years 2018 and 2019. The effect of four different formulations (bio-stimulants and foliar preparations; control, amalgerol 15,000 cc ha–1, millerplex 450 cc ha–1, sugarxpress 12,000 cc ha–1, in three equal applications) on flower yield, essential oil content and yield were studied in a completely randomized experimental design under five replicates. The bio-stimulants application produced significantly higher flower shoots and essential oil yield comparing with control. The use of millerplex resulted to higher essential oil yield in higher values than the reported in literature, while the use of 'amargerol' produced flowering shoots with stable essential oil content for both experimental years. Therefore, the use of the above mentioned bio-stimulants is suggested to be used from the establishment year and thereafter, while further investigation on essential oil quality should be considered. © 2020 Informa UK Limited, trading as Taylor & Francis Group

Could bio-stimulators affect flower, essential oil yield, and its composition in organic lavender (Lavandula angustifolia) cultivation?

Soil-climatic conditions of Greece and Mediterranean basin in general are favor for the development of aromatic-medicinal plants. A great aromatic-medicinal plant that is cultivated on a large scale in Greece and in Mediterranean basin in general for its essential oil is lavender. Lavender organic cultivation is facing a serious problem with Rhizoctonia and Fusarium fungal infections resulting in the most cases to the destruction of the cultivation. The aim of the current study was to investigate the effect of bio-stimulators to flower and essential oil yield and its composition. For the purposes of the study field experiments were established in Microkastro Vojo Kozanis (40°14′44.25″N, 21°30′25.87″E) in 2018 and 2019, using a complete randomized experimental design. There was investigated the effect of different treatments (i). control, (ii). amalgerol 15000 mL ha−1, (iii). millerplex450 ml ha−1, (iv). sugarXpress 12000 mL ha−1, in three equal applications) on flower, essential oil yield and composition under five replicates. The results refer to the sixth and seventh lavender’ growing year. It was found that flower (spike) yield was decreased by 50% at the second experimentation year while the use of the bio-stimulators had a statistically significant effect compared with control, indicating their positive effect. In essential oil content case, amalgerol treatment was found to have the same content for both growing years. Finally, the identified essential oil components were 48, and there were found many differences to the composition between the tested treatments. © 2020 Elsevier B.V

Lavender organic cultivation yield and essential oil can be improved by using bio-stimulants

Lavender is an aromatic-medicinal plant, cultivated in Greece and in Mediterranean basin in general. The aim of the current study was to investigate if the use of bio-stimulants could increase the yield of the flowering shoots and the essential oil content even from the establishment year. For the purposes of the study, in Microkastro Vojo Kozanis, lavender experimental field was established on November 2017 and the results refer to the experimentation years 2018 and 2019. The effect of four different formulations (bio-stimulants and foliar preparations; control, amalgerol 15,000 cc ha–1, millerplex 450 cc ha–1, sugarxpress 12,000 cc ha–1, in three equal applications) on flower yield, essential oil content and yield were studied in a completely randomized experimental design under five replicates. The bio-stimulants application produced significantly higher flower shoots and essential oil yield comparing with control. The use of millerplex resulted to higher essential oil yield in higher values than the reported in literature, while the use of 'amargerol' produced flowering shoots with stable essential oil content for both experimental years. Therefore, the use of the above mentioned bio-stimulants is suggested to be used from the establishment year and thereafter, while further investigation on essential oil quality should be considered

Influence of trichoderma harzianum and glomus mycorrhiza on biomass and essential oil yield of organic ocimum basilicum cultivation

The growing interest in dealing with the cultivation of aromatic – medicinal plants requires the study of factors related to the production process, which includes the development of plants in field, as well as their processing and the receipt of essential oils. The aim of this study was to investigate the effect of two organic formulations, Trichoderma harzianum (T22), and Glomus mycorrhiza (G), in the cultivation of seedlings of Ocimum basilicum variety "Genovese" fresh and dry weight, as well as essential oil content and its quality characteristics. For the purposes of the study a field experiment was conducted in 2018 and 2019, using a factorial experimental design, with two factors: a) control, b) Trichoderma harzianum (T22) and c) Mycorizas Glomus (G) under four replicates. There was found statistically significantly difference between the two harvests occurred in each year on fresh and dry weight while no significant difference was recorded through the tested treatments. Furthermore, there was recorded a decrease in the essential oil yield between the cultivating years (approximately 14%), and also between annual cuts. Finally, the most remarkable finding was that although the different treatments did not show significant differences in the quantitative characteristics of sweet basil in the case of quality characteristics with mycorrhiza treatments essential oil having 40 identified ingredients instead of 21 that identified in control. Therefore, the use of these organic formulations is suggested to be used only in case of essential oil production where a predetermined quality of essential oil will be known. © 2020, University of Montenegro. All rights reserved

Irrigation and nitrogen application affect Greek oregano (Origanum vulgare ssp. hirtum) dry biomass, essential oil yield and composition

Oregano is a perennial crop native to the mountains, which has been extensively cultivated in the last decade. Due to the growing interest in oregano cultivation, the aim of this study was to investigate the effect of irrigation and nitrogen fertilization on the yield of Greek oregano and the production of essential oil in order to increase the harvested yield without reducing the quality of the product. For the purposes of the study, field experiments were established in 2016 and 2017 using a factorial split-plot experimental design with main factor irrigation (I1: rainfed, I2: 100 % ETo) and sub factor nitrogen fertilization (N1: 0, N2: 150, and N3: 300 kg ha−1) under four replicates. Total yield measured by final samplings where plants were cut at 5–8 cm above ground. Essential oil content was determined, using a Clevenger-type distillation apparatus. Irrigation had not a significant effect on yield, with irrigated treatments producing almost the same yield with the rainfed treatments (3650 and 3250 kg ha-1, respectively), probably due to the satisfactory precipitation during the growing period. In addition, nitrogen fertilization had a significant effect on yield and on essential oil. The higher yield and essential oil production were found for the irrigated and fertilized with the higher nitrogen testing amount (I2N3) treatment (4750 and 275 kg ha-1 dry leaves and flower biomass and essential oil, respectively). Therefore, Greek oregano seems to be a promising cultivation in areas characterized by a typical Mediterranean climate with satisfactory precipitation (>250 mm) during growth period, characterized by satisfactory yields. © 2020 Elsevier B.V

Effect of irrigation and fertilization levels on mineral composition of cannabis sativa L. Leaves

A field experiment was conducted in central Greece to study, the effect of two irrigation (I1: 100% ETo, I2: 60% ETo) and N-fertilization levels (N1: 244, N2: 184 kg ha-1), on the nutrients concentration of Cannabis sativa leaves (cv. 'Fibranova'). The N, K, Ca, Mg, P -concentration in the leaves was ranged by 2.8 to 3.51%, 1.8 to 2.57%, 1.96 to 2.17%, 0.86 to 0.88%, and 0.3 to 0.37% respectively, while by the micronutrients the iron showed the highest concentration that ranged by 129 to 139.8 mg kg-1dw. The treatment I1F1, where the highest level of irrigation and N -fertilization was applied, compared to the other treatments, showed the highest dry biomass yield, however, in the leaves the highest concentrations of N, K, Mn and Cu were not observed. Moreover, it was found that the N, K, Ca, Mg, P and Fe removal only by one ton dry biomass of leaves was ranged by 28 to 35.12 kg, 18.01 to 25.65 kg, 19.6 to 21.7 kg, 8.34 to 8.75 kg, 3.01 to 3.70 kg and 0.129 to 0.140 kg, respectively. These results could contribute optimal fertilizer application and therefore to the reduction of production costs of the crop. © 2019 Academic Press

Matricaria chamomilla L. (German chamomile) flower yield and essential oil affected by irrigation and nitrogen fertilization

Matricaria chamomilla is one of the most important medicinal herbs. The aim of this study was to investigate irrigation and N-fertilization effect on German chamomile yield and essential oil production. For the purposes of this study, field experiments were established at the Experimental Farm of the University of Thessaly, Larissa, Greece, in 2016 and 2017. The experimental design was a factorial split-plot design with main factor irrigation (I1: rainfed, I2: 100% ETo) and sub factor N-fertilization (F1: 0, F2: 80, and F3: 160 kg ha-1) with four replications. Flower yield measured by samplings at the ideal collection stage (2/3 of the rounds of tubes have been opened on the elevated flowering plant). Essential oil content was determined, using a Clevenger-type distillation apparatus and essential oil analysis by a GC-MS on a fused silica DB-5 column. Irrigation had a significant effect on yield, with irrigated treatments producing higher yield in comparison with rainfed treatments (5,250 and 2,200 kg ha-1, fresh and dry flowers, respectively). Furthermore, N-application had also a significant effect on yield, with the higher N-supply producing higher yield. The highest yield and essential oil production were found for the irrigated and fertilized treatment with the higher N-dressing (I2F3, 3,800 and 25 kg ha-1 dry flowers and essential oil yield, respectively). Moreover, it was found that the irrigated treatments produced lower amount of essential oil, while N-fertilization had a positive effect on α-bisabolol and chamazulene and a negative effect on bisabolol oxide A. Although irrigation had a negative impact on the content of essential oils, the high increase in yield led to a maximization of the essential oil production for the irrigated cultivation with maximum nitrogen fertilization. Therefore, chamomile seems to be a promising annual cultivation in Greece which can be established in areas of similar environmental conditions producing satisfactory yields. © 2020 United Arab Emirates University

The effect of organic fertilizers and biostimulants on oregano (origanum vulgare) yield and essential oil

The purpose of this study was to investigate the effect of biological fertilizers and a natural origin stimulant in oregano cultivation. For the purposes of the study a field experiment was established in Larissa (central Greece). There was used a factorial experimental design with three factors: a) T1: Control, b) T2: Application of 1500 kg ha-1 Italpollina + 2 sprays with Auxym and c) T3: Application of 1500 kg ha-1 Solfero + 2 sprays with Auxym under four replications. The fresh and dry total weight of T2 and T3 were reduced to rates of approximately 4% and 6% respectively, compared to those of T1. Contrary to the above observation, the dry drogue weight of T1 plants was reduced by approximately 13.5% compared to T2 and by 7% compared to T3. Finally, essential oil yield was higher in T2, at rates of 21% and 15% compared to T1 and T3 respectively. Copyright © 2020 for this paper by its authors. Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0)