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

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

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)