Journal of Organic Farming of Medicinal Plants
Volume:1 Issue: 1, Winter-Spring 2022

Purple coneflower (Echinaceae purpurea (L.) Munch) root is a rich source of phenolic components used in pharmaceutical industries and the content of phenolic components depends on many factors such as drought stress and nitrogen (N) nutrition. This experiment was conducted in Lordegan, Iran, from 2014 to 2016, to investigate the effect of N and nitroxin on the content of phosphorus, potassium and nitrate, yield, content and yield of phenol compound of purple coneflower root under three irrigation regimes. Irrigation after 25%, 50% and 75% of soil water depletion, as the main factor and 0 kg N ha-1 (control), nitroxin (containing Azotobacter and Azospirillium bacteria), 40 kg N ha-1, a combination of nitroxin and 40 kg N ha-1 and 80 kg N ha-1 were considered as the sub-factor and arranged as a split plot in the randomized complete block design with three replications. Nitrogen application increased potassium content and root yield and also phosphorus content in all irrigation levels. The highest root nitrate accumulation was obtained by the application of 80 kg N ha-1 in all irrigation treatments. Irrigation after 75% of soil water depletion decreased potassium content and root yield. The highest root yield was achieved from nitroxin+40 kg N ha-1. Root phenolic compounds were raised by increasing irrigation intervals, and N consumption decreased them at each irrigation regime. The highest phenolic compound yield was obtained from the application of nitroxin in irrigation after 75% of soil water depletion. Generally, irrigation after 75% of soil water depletion and utilization of nitroxin is suggested for the best quantity and also quality root production in the studied region.

Intensive cultivation has led to a rapid decline in organic matter and nutrient levels besides affecting the physical properties of soil. The sustainability of production systems has become an important issue throughout the world. Black cumin (Nigella sativa L.) is one of the most widely used medicinal and industrial plants. Furthermore, today, using organic and biofertilizers as a tool to achieve sustainable agriculture was considered. The current study was conducted as a factorial experiment at the Forest and Rangeland Research Institute of Iran in 2019 as a randomized complete block design with three replications. The treatments included six vermicompost levels (0, 3, 6, 9, 12, and 15 tons ha-1), and the foliar application of amino acid at 3 levels (no foliar application, foliar application at the beginning of the flowering stage and foliar application at the beginning of the encapsulation stage). The results of the study showed that amino acids, vermicompost, and their interaction had a significant effect on leaf yield. Moreover, the interaction of amino acid × vermicompost significantly affected biological yield and essential oil yield. Comparing the mean oil yield showed that the highest oil yield (73.22 kg ha-1) was related to the 6 tons of vermicompost × no foliar application of amino acids. The results showed that using vermicompost and amino acids could increase the quantity and quality of Nigella sativa L. in sustainable cropping systems.

Water scarcity has become an increasingly important factor contributing to crop yield decline in arid regions. Soil amendments and certain growth regulators are some strategies used to mitigate the negative effects of drought stress. This study aimed to investigate the effects of biochar and salicylic acid on some physiological and biochemical properties of Borago officinalis L. under water deficit conditions. This experiment was conducted as a split-plot factorial experiment based on a randomized complete block design with four replicates. The factors were irrigation regimes according to the percentage of water requirement (100% WR, 75% WR, and 50% WR) in the main plots, biochar application (0, 5, and 10 ton ha-1) and foliar application of salicylic acid (0, 0.5 mM) in the subplots. This study was conducted in the research field of Shahrood University of Technology, Shahrood, Iran, in two cropping years, 2017 and 2018. The results showed that the total amount of soluble sugars decreased with an increase in the irrigation regime; however, the leaf antioxidant enzymes (SOD, CAT, and POX) and leaf proline concentration significantly increased in the 75% WR irrigation regime and slightly decreased in the 50% WR irrigation regime in both years. Applying salicylic acid (0.5 mM) significantly increased the leaf proline by 50% and 55% in irrigation regimes of 100% WR and 75% WR, respectively, in both years. It also modified the total amount of soluble sugars in both years. In addition, salicylic acid also stimulated leaf antioxidant enzymes under 100%WR under 75% WR and 50% WR irrigation regimes in both years. Biochar application reduced leaf proline concentration by 27% and 28% (10 ton ha-1) under 100% WR and 75% WR irrigation regimes, respectively. An improvement of all antioxidant enzymes via biochar application was found in both years. Application of 5 ton ha -1 biochar mitigated relative water content in 75% WR. Our results clearly indicated that applying exogenous salicylic acid in combination with biochar could be a promising approach to improve plant stress tolerance mechanisms under water deficit conditions.

The main objective of this investigation was to study the effects of manure and amino acid foliar application on the quantity and quality of essential oil in coriander. The experiment was conducted at the research fields of Islamic Azad University, Roudehen, Iran in the spring of 2017. The experiment was carried out as a factorial arrangement based on a randomized complete block design with three replications. The factors were manure application at five levels (0, 3, 6, 9, and 12 ton ha-1) and amino acid foliar application at two levels (control and foliar application). Results showed that the highest essential oil content (0.56%) and geranyl acetate (2.61%) were obtained by using 12 ton ha-1 of manure. But, applying 9 ton ha-1 of manure resulted in maximum alpha-pinene (10.83%) and linalool (69.93 %). Mean comparison showed that amino acid foliar application caused maximum essential oil content (0.5%), alpha-pinene (10.35%), and linalool (68.20%). Gamma-terpinene and orto-cimene content in essential oil were significantly affected by the interaction of treatments so that the maximum gamma-terpinene (10.16%) was obtained by using 6 ton ha-1 of manure with amino acid foliar application whereas the highest orto-cimene content (1.58%) was observed by using 9 ton ha-1 of manure with amino acid foliar application. Overall, the results of this experiment show that manure and foliar application of amino acid play an important role in improving the quality of the essential oil of coriander in a sustainable production system.

Intensive cultivation has led to a rapid decline in organic matter and nutrient levels besides affecting the physical properties of soil. The sustainability of production systems has become an important issue throughout the world. This study assessed the effects of nitrogen fertilizer and vermicompost on chamomile's qualitative and quantitative yield. The investigation was conducted at the Research Fields of Ran Company in Firouzkouh, Iran, in the spring of 2017. Treatments consisted of 1) Control, 2) 100% nitrogen from urea, 3) 100% nitrogen from ammonium nitrate, 4) 75% nitrogen from urea and 25% from vermicompost, 5) 75% nitrogen from ammonium nitrate and 25% from vermicompost, 6) 50% nitrogen from urea and 25% from vermicompost, 7) 50% nitrogen from ammonium nitrate and 25% from vermicompost, 8) 25% nitrogen from urea and 25% from vermicompost, 9) 25% nitrogen from ammonium nitrate and 25% from vermicompost and 10) 100% nitrogen from vermicompost. The results of this investigation showed that the maximum plant height (67.03 cm) and plant weight (93.21 g plant-1) were obtained by 200 kg ha-1 urea. The application of 202.5 kg ha-1 ammonium nitrate + 1.5-ton ha-1 vermicompost, caused maximum flower diameter. The highest fresh flower yield (7539.45 kg ha-1), dry flower yield (1715.93 kg ha-1) and essential oil yield (6.95 kg ha-1) were obtained in plots that received 135 kg ha-1 nitrate ammonium + 3-ton ha-1 vermicompost. It seems using vermicompost could enhance the quantitative and qualitative characteristics of chamomile.