Dry Flower Yield Research Articles

Harvesting Light: The Interrelation of Spectrum, Plant Density, Secondary Metabolites, and Cannabis sativa L. Yield

The approaching legalisation and associated increasing demand for medicinal and recreational Cannabis sativa L. will lead to a growing relevance for lighting systems designed for Cannabis sativa L. The interplay between plant density, light spectrum, light distribution, yield, and secondary metabolite distribution within the plant has not yet been studied. To fill this knowledge gap, a CBD-dominant Cannabis sativa L. strain was grown in a greenhouse experiment with two plant densities (2.66 and 12 plants −1 m−2) under two different light spectra. The chosen light spectra were two LED fixtures, Solray385 (SOL) and AP67, with an R: FR ratio of 12.9 and 3.7, respectively. The results indicated that light-induced effects on individual plants can be transferred to the plant stock. A low R: FR ratio induced a 16% increase in dry flower yield in the last ten days of flowering, while a change in the light spectrum could increase the potential maximum plant density per square metre. The two spectra did not affect (CBD + CBDA) yield, as a lower flower yield compensated for a higher concentration. CBDA concentration was not significantly affected by plant density. In contrast, the higher density led to an increased total cannabidiol concentration (CBD + CBDA) and altered the distribution of terpenes. Here, the light distribution over the plant stock is particularly decisive, as a more homogenous illumination led to an increased terpene concentration of up to 41%. A Photon Conversion Efficacy (PCE) of 0.05 g mol−1 under SOL and 0.06 g mol−1 under AP67 was achieved. Plants in the centre under the highest light intensity of 1200 PAR showed up to 48% reduced efficacy. These results strongly suggest that light intensity needs to be fine-tuned to the cultivation system to prevent a reduction in efficacy, resulting in yield and quality losses.

Exploring Chemical and Cultural Weed Management for Industrial Hemp Production in Georgia, USA

Industrial hemp (Cannabis sativa) production is complex, with strict regulatory constraints and challenges associated with a lack of labeled pesticides due to its status as a novel crop in the US. Four experiments were conducted in 2020 and 2021 to establish herbicide tolerances for hemp production in the coastal plain of Georgia, USA. Objectives included evaluating hemp response to pretransplant or posttransplant herbicides, determining if planting method influenced herbicide injury from residual preplant applied herbicides, and understanding how plastic mulch may influence hemp flower yields. When applied one day prior to transplanting, maximum hemp crop visual injury was less than 12% compared to the untreated control, with acetochlor, flumioxazin, fomesafen, pendimethalin, and norflurazon while dithiopyr, halosulfuron, isoxaben, and isoxaflutole resulted in greater than 50% injury. Posttransplant applications of S-metolachlor, acetochlor, pendimethalin, and clethodim resulted in less than 15% injury while halosulfuron, metribuzin, trifloxysulfuron, imazethapyr, and prometryn applications resulted in greater than 50% injury to plants. Preplant and posttransplant applied herbicides were found to have little effect on total tetrahydrocannabinol (THC), cannabidiol (CBD), or total cannabinoids in the dry flower after harvest. In a separate experiment, injury from halosulfuron and metribuzin was 52% to 56% less when planted with a mechanical transplanter as compared to the practice of using a transplant wheel to depress a hole in the soil followed by hand transplanting. In the final experiment, hemp dry flower yield in a non-plastic mulched (bareground) system was similar to that in a plastic mulched system. However, early season plant above-ground biomass was less in the plastic mulched system, which may have been due to elevated soil temperatures inhibiting early season growth.

Determination of Yield and Quality Characteristics of Lavandula Cultivars in the Kahramanmaras Region

In recent years, there has been a growing interest in herbal remedies for therapeutic purposes. Aromatic plants have become a significant source of raw materials for the fragrance, food, and cosmetics industries. Additionally, the emergence of new applications and the trend towards natural nutrition and alternative healing methods, often referred to as "going natural," have increased the interest in medicinal and aromatic plants in our country, as well as in other countries around the world. In this study were investigated to determine yield and quality characteristics of seven different lavender (Lavandula intermedia Emeric ex Loisel. = L. hybrida L.) (Grasso, Süper-A, Seguret, Dutch, Abrial, Akmeşe, English) cultivars under dry and irrigated cultivation in Kahramanmaraş conditions between 2019 and 2020. The research was carried out in a randomized block design with 4 replications. Fresh stem flower yield was the highest variety Grasso(672.81kg/da). The lowest fresh stem flower yield was found in Seguret variety with 611.33kg/da The highest dry stemless flower yield was determined in Grasso variety with 59,66 kg/da. There were significant differences determined between cultivars the end of 2 years. The highest average fresh stem flower yield (693.067 kg/da) and the highest average dry branched flower yield (252.588 kg/ha) were measured in GRASSO variety.

Flower yield potential of Pyrethrum (<em>Chrysanthemum cinerariaefolium</em> L.) under various NPK Levels in the Lower Hills of Uttarakhand, India

Purpose: A favorable environment is available for the cultivation of Pyrethrum in the hilly regions of India, as well as in some mountainous areas of India. In view of the demand for Pyrethrin, it is very necessary to promote the huge cultivation of Pyrethrum. There is no misconception that research work has not been done to promote Pyrethrum, but the data related to the assessment of the right amount of nutrients required for the crop is not available in research related to agrotechnology. If the crop is to be taken as a ratoon crop, then it is very important to estimate the amount of nutrients for single recommendation of crop cultivation. Research Method: A research experiment was conducted in the year 2021 at the CSIR-Central Institute of Medicinal and Aromatic Plant Research, Centre Purara, Bageshwar (Uttarakhand) to study the flower yield potential of Pyrethrum under various NPK levels in the lower hills of Uttarakhand. The experiment was carried out in Complete Randomized Block Design. The six different levels of NPK (kg ha-1) were taken as treatments, i.e., control, 60:60:20, 80:70:30, 100:80:40, 120:90:50, and 150:100:60. Various plant growth and yield parameters considered in the study include plant height (cm), plant diameter (cm), number of flower heads, fresh flower weight plant-1 (g), dry flower weight plant-1(g), fresh flower yield (kg ha-1), dry flower yield (kg ha-1), Pyrethrin concentration (%) and yield (kg ha-1). Findings: Based on the research findings, it seems that the NPK level of 120:90:50 is the best combination to obtain the highest dry flower yield (310.49 kg ha-1) in the lower hills of Uttarakhand. However, the fresh flower weight obtained was the highest under the NPK level of 100:80:40 i.e., 840.47 kg ha-1, but it’s dry flower yield estimated was 301.93 kg ha-1 which was the second highest yield after 310.49 kg ha-1. This could be due to the difference in moisture levels in fresh flowers at the time of harvesting.Research Limitation: Considering the climate of the hilly regions of Uttarakhand, not much work has been done to assess and standardize the proper amount of nutrients required for Pyrethrum crop cultivation, which needs to be done.Originality/ Value: In the hilly areas of Uttarakhand, farmers are interested in the cultivation of Pyrethrum, but if farmers will adopt this crop cultivation as a ratoon crop, then in such a situation it is absolutely necessary to assess the proper amount of nutrients. This research will prove helpful in promoting the cultivation of Pyrethrum in the hilly areas of Uttarakhand.

Evaluation of the Possibility of Establishing Certain Organic Cultivation Packages as Nutrient Sources for Chamomile (Matricaria chamomilla L.) Cultivation at Temperate Region of Uttarakhand, India

An utmost attempt was made to investigate the response of Chamomile (Matricaria chamomilla L.) to certain types and doses of organic manures at under open condition at temperate regions of Uttarakhand during the year 2019-2020. The study comprised of varying levels of three different organic manure sources namely, FYM, compost and vermicompost, along with a check treatment replicating thrice having plot having dimensions 1 m× 1 m with a spacing of 20 cm × 20 cm. The experiment was laid out in a randomized complete block design (RCBD). Forty-five (45) days old chamomile seedlings (attained about 10-15 cm in height) were transplanted during October, 2019 under open field condition. The soils of the experimental site were tested favourable with respect to some of the basic physical and chemical properties. The results revealed that maximum plant height (48.26 cm), number of branches per plant (35.40) and plant spread (33.09 cm) were significantly higher under T4 (FYM @ 25 t/ha) application at 180 days after transplanting. Application of T10 (VC @ 4 t/ha) produced early flowering (119.73 days). At bud initiation stage the highest total fresh (33.12 q/ha) and dry (7.59 q/ha) biomass yield were found in T4 (FYM @ 25 t/ha). At flowering stage maximum value of total fresh (60.02 q/ha) and dry (12.70 q/ha) biomass yield were found in T10 (VC @ 4 t/ha). The results, further revealed that T10 provided the fastest crop growth rate (0.86 g/m2/day). The highest number of flowers per plant (139.73), fresh flower yield (67.35 q/ha), dry flower yield (13.95 q/ha) and maximum cost: benefit (1:3.56) were obtained in plots which received FYM @ 25 t/ha. All the organic input treatments performed better over control and the treatment FYM @ 25 t/ha shall be recommended for profitable organic cultivation of chamomile.

Moving Away from 12:12; the Effect of Different Photoperiods on Biomass Yield and Cannabinoids in Medicinal Cannabis

The standard practice to initiate flowering in medicinal cannabis involves reducing the photoperiod from a long-day period to an equal duration cycle of 12 h light (12L)/12 h dark (12D). This method reflects the short-day flowering dependence of many cannabis varieties but may not be optimal for all. We sought to identify the effect of nine different flowering photoperiod treatments on the biomass yield and cannabinoid concentration of three medicinal cannabis varieties. The first, "Cannatonic", was a high cannabidiol (CBD)-accumulating line, whereas the other two, "Northern Lights" and "Hindu Kush", were high Δ9-tetrahydrocannabinol (THC) accumulators. The nine treatments tested, following 18 days under 18 h light/6 h dark following cloning and propagation included a standard 12L:12D period, a shortened period of 10L:14D, and a lengthened period of 14L:10D. The other six treatments started in one of the aforementioned and then 28 days later (mid-way through flowering) were switched to one of the other treatments, thus causing either an increase of 2 or 4 h, or a decrease of 2 or 4 h. Measured parameters included the timing of reproductive development; the dry weight flower yield; and the % dry weight of the main target cannabinoids, CBD and THC, from which the total g cannabinoid per plant was calculated. Flower biomass yields were highest for all lines when treatments started with 14L:10D; however, in the two THC lines, a static 14L:10D photoperiod caused a significant decline in THC concentration. Conversely, in Cannatonic, all treatments starting with 14L:10D led to a significant increase in the CBD concentration, which led to a 50-100% increase in total CBD yield. The results show that the assumption that a 12L:12D photoperiod is optimal for all lines is incorrect as, in some lines, yields can be greatly increased by a lengthened light period during flowering.

Comparison of different helichrysum species in terms of agro-morphological characteristics and essential oil content

Helichrysum species belonging to the Asteraceae family are popularly known as goldengrass, mantuvar, guddeme flower and immortelle in our country. Helichrysum species, which are commonly found in nature in Anatolia, are consumed as herbal tea. Helichrysum essential oils are used in folk medicine to protect against colds, kidney stones, stomach ailments, coronary heart disease, stroke and some cancer derivatives, thanks to their antioxidant, antiviral, antifungal, antimicrobial, anti-inflammatory properties and phenolic compounds. This research was carried out to compare agro-morphological characteristics and essential oil ratio between cultured Helichrysum italicum (HI) and naturally distributed Helichrysum stoechas (HS) species. The experiment was established in Ege University Ödemiş Vocational School’s land in April 2022 with HS and HI species according to the Random Blocks Trial Design with 3 replications. In the study, plant height, green herb yield, dry herb yield, fresh flower yield, dry flower yield and essential oil ratio parameters were investigated. The results of the analysis of variance with the data of the investigated characteristics, it was determined that the culture form HI may be a more suitable medicinal plant for the ecological conditions of İzmir-Ödemiş compared to HS, which spreads in the flora.

Replacing chemical fertilizers with organic and biological ones in transition to organic farming systems in saffron (Crocus sativus) cultivation

To evaluate the response of saffron to animal manure, and biological and chemical fertilizer in an arid climate, an experiment was performed as split plots based on a randomized complete blocks design with three replications during three consecutive crop growth seasons (2015–2018) at the Research Farm of University of Gonabad, Iran. The experimental treatments included application (60 t ha−1) and non-application (control) of manure as the main plot and the use of biosulfur (5 kg ha−1), biophosphate (3 L ha−1), nitroxin (3 L ha−1), chemical fertilizer (150, 100, and 100 kg ha−1 of urea, triple superphosphate, and potassium sulfate, respectively), and no fertilizer application (control) as the sub-plot. The results showed a highly significant response of the quantitative traits of saffron to the application of manure, which increased the leaf, flower, and corm indices of saffron by a mean of 15.1–35.7% than control. The interaction effect of manure with biological and chemical fertilizers for leaf, flower, and weeds indices of saffron was significant. There was no significant difference between the interaction treatments of manure and chemical fertilizer with nitroxin and biophosphorus fertilizers in most of the mentioned traits in the three experiment years. The simultaneous application of these fertilizers increased the average by about 60, 105, 135, 110, 165, and 55% of the leaf dry weight, the number of flowers, fresh flower yield, dry flower yield, dry stigma yield, and weed dry weight of saffron, respectively as compared to control. There was no significant difference between the chemical fertilizer with nitroxin or biophosphate in terms of the effect on the traits related to saffron corm so the use of these fertilizers, as compared to control, increased replacement corm weight, replacement corm size, and bud number per corm by, respectively, about 35, 60, and 40% on average. The chemical and biological fertilizers improved the content of crocin, picrocrocin, and safranal of saffron stigma. The best results were obtained from the use of chemical fertilizers, although no significant difference was observed between this treatment and the nitroxin and biophosphate treatments. Overall, the results of this three-year experiment show a very high response of the saffron plant to the simultaneous use of manure and biological fertilizers and, therefore, it is possible to replace chemical fertilizers with organic and biological fertilizers in saffron cultivation to implement organic agriculture and achieve acceptable quantitative and qualitative yields in areas similar to the experiment location.

Changes in flower yield, essential oil yield and oil composition after soil and foliage zinc and iron fertilization in German chamomile

In order to analyze the effects of zinc (Zn) and iron (Fe) on growth, yield, oil production and oil quality of German chamomile, an open field experiment was conducted at the Research Center, CSIR-Central Institute of Medicinal and Aromatic Plants (CIMAP), Pantnagar, Uttarakhand, India in 2019–2020 and 2020–2021. The experiment was set according to Randomized block design (RBD) with 7 treatments and three replications. Treatments were as follow: T1: control (without Zn or Fe fertilizers), T2: Foliar Fe spray @ 0.5%, T3: Foliar Fe spray @ 1.0%, T4: Foliar Zn spray @ 0.5%, T5: Foliar Zn spray @ 1.0%, T6: Mixing of Zn in soil @ 30 kg/ha before transplanting, T7: Mixing of Fe in soil @ 30 kg/ha before transplanting. Foliar spray of zinc (Zn) and iron (Fe) was conducted twice before flowering throughout the crop growth period. Obtained results showed that the plant height, canopy, number of flowers, fresh & dry flower yield, oil production, oil content and oil composition were radically increased and improved by foliar spray and soil mixing of Zn and Fe, compared to control. The maximum fresh flower & dry flower yield, oil content, and oil production were recorded in the treatment of foliar spray of Zn @ 0.5% followed by 1.0% in 2019–2020 and 2020–2021. The results also showed that Zn and Fe improved the oil quality and increased the concentration of major compounds like chamazulene, Z-spiroether, α-bisabolol oxide-A & B in oil compared with control.

Determination of Critical Weed Competition Period in Chamomile (Matricaria chamomilla L.) Production at Wondo Genet, Southern Ethiopia

The study was carried out at Wondo Genet to determine the critical weed competition period for growth, yield, and yield components of the chamomile plant. The weed competition duration had a significant influence on plant height, the number of primary branches/plants, fresh stem yield/plant, fresh leaves yield/plant, fresh and dry flower/plant, fresh and dry flower yield/ha, essential oil content (v/w) and yield kg/ha. The highest fresh and dried flower yield (3780.10 kg/ha) and (798.32 kg/ha) was recorded from weed-free check followed by weed-free for 60 DACE (Days After Crop Emergence) (3652.10 kg/ha) and (789.43 kg/ha), respectively. The maximum essential oil content and yield were recorded from the weed-free check (0.79v/w) and (6.25 kg/ha) whereas the minimum was in the weedy-check (0.10 v/w) and (0.15kg/ha), respectively. The yield losses of chamomile were estimated based on the fresh and dry flower and essential oil yield per hectare. Thus, the highest fresh and dry flower yield losses were recorded from the weedy-check (83.58%) and (81.05%) while the lowest was from weed-free check (0.00%), respectively. The highest essential oil yield loss was also recorded from the weedy for 60DACE (97.92%) followed by weedy-check (97.60%). To determine the beginning and the end of the critical period of crop-weed competition 5 and 0% acceptable yield loss levels were used. Therefore, to reduce the yield losses of chamomile by more than 10% and higher economic return, plants must be kept weed-free within 40 to 60DACE to reduce the risk of economic yield losses as it is the critical period of weed-crop competition in chamomile plants.

Impact of Three Different Light Spectra on the Yield, Morphology and Growth Trajectory of Three Different Cannabis sativa L. Strains.

Cannabis is one of the oldest cultivated plants, but plant breeding and cultivation are restricted by country specific regulations. Plant growth, morphology and metabolism can be manipulated by changing light quality and intensity. Three morphologically different strains were grown under three different light spectra with three real light repetitions. Light dispersion was included into the statistical evaluation. The light spectra considered had an influence on the morphology of the plant, especially the height. Here, the shade avoidance induced by the lower R:FR ratio under the ceramic metal halide lamp (CHD) was of particular interest. The sugar leaves seemed to be of elementary importance in the last growth phase for yield composition. Furthermore, the last four weeks of flowering were crucial to influence the yield composition of Cannabis sativa L. through light spectra. The dry flower yield was significantly higher under both LED treatments compared to the conventional CHD light source. Our results indicate that the plant morphology can be artificially manipulated by the choice of light treatment to create shorter plants with more lateral branches which seem to be beneficial for yield development. Furthermore, the choice of cultivar has to be taken into account when interpreting results of light studies, as Cannabis sativa L. subspecies and thus bred strains highly differ in their phenotypic characteristics.

Comparing of Cultivated Annual and Perennial Calendula officinalis L. Species

The aim of this study was to determine the highest dry flower yield and essential oil content of yellow and orange flowered annual and perennial marigold plants. Annual and perennial Calendula officinalis L. plant seeds with yellow and orange flower obtained from Research and Application Center of Botanical Garden and Herbarium, Ege University were used as a study material. The experiment was established to the 1000 m2 area of Ege University Odemis Vocational School field according to split-split plot parcel design with three replications on 28th of March 2016. Flowers were harvested when the plants in full blossom stage, every ten days. Annual yellow and orange flowers and perennial yellow and orange flowers were evaluated separately for each harvest. Totally seven harvest were done. All fresh flowers were weighed after then dried in a drying cabinet at 30 oC and essential oil contents were obtained by hydro distillation method. The highest dry flower yields for perennial plants were provided for yellow flowered plants; at 7.54 kg da-1 and for orange flowered plants; 7.28 kg da-1. The highest essential oil contents in perennial were determined for yellow flowered plants as 0.051%, and orange flowered plants; 0.020%. In general, it can be said that content of essential oil is higher in perennial plants than single years.

Cannabis lighting: Decreasing blue photon fraction increases yield but efficacy is more important for cost effective production of cannabinoids.

LED technology facilitates a range of spectral quality, which can be used to optimize photosynthesis, plant shape and secondary metabolism. We conducted three studies to investigate the effect of blue photon fraction on yield and quality of medical hemp. Conditions were varied among studies to evaluate potential interactions with environment, but all environmental conditions other than the blue photon fraction were maintained constant among the five-chambers in each study. The photosynthetic photon flux density (PPFD, 400 to 700 nm) was rigorously maintained at the set point among treatments in each study by raising the fixtures. The lowest fraction of blue photons was 4% from HPS, and increased to 9.8, 10.4, 16, and 20% from LEDs. There was a consistent, linear, 12% decrease in yield in each study as the fraction of blue photons increased from 4 to 20%. Dry flower yield ranged from 500 to 750 g m-2. This resulted in a photon conversion efficacy of 0.22 to 0.36 grams dry flower mass yield per mole of photons. Yield was higher at a PPFD of 900 than at 750 μmol m-2 s-1. There was no effect of spectral quality on CBD or THC concentration. CBD and THC were 8% and 0.3% at harvest in trials one and two, and 12% and 0.5% in trial three. The CBD/THC ratio was about 25 to 1 in all treatments and studies. The efficacy of the fixtures ranged from 1.7 (HPS) to 2.5 μmol per joule (white+red LED). Yield under the white+red LED fixture (10.4% blue) was 4.6% lower than the HPS on a per unit area basis, but was 27% higher on a per dollar of electricity basis. These findings suggest that fixture efficacy and initial cost of the fixture are more important for return on investment than spectral distribution at high photon flux.

Genetic improvement of pyrethrum (Tanacetum cinerariifolium Sch. Bip.) through gamma radiation and selection of high yield stable mutants through seven post-radiation generations

Purpose To increase the size of the flowers for easy plucking, flower yield, pyrethrins content (%), and elite mutant selection in pyrethrum. Materials and methods To increase pyrethrum production and acclimatize in north Indian plain condition, a genetic improvement program was undertaken to widen the range of variations for size and yield of flowers and pyrethrins content (%) in pyrethrum crop. Pyrethrum seeds of the variety Avadh were irradiated with gamma rays at 20 to 300 Gy doses in Gamma chamber 5000 (cobalt-60 research irradiator). Results Observations gathered visually in M1 based on vigor, synchronization of flowering, and flower’s size. Out of 90 M2 families, 20 mutants were raised in M3 along with the check-in preliminary evaluation trial. The four promising mutants, 1 (20 Gy-3), 7 (40 Gy-5), 10 (40 Gy-8), 14 (60 Gy19-10) was grown for four years in a bench-scale trial (randomized block design, replicated thrice) to test the yield performance and selection of high yielding elite mutant (s). It has been found that pyrethrum is sensitive to gamma rays irradiation and produced a high range of qualitative and quantitative variations. After massive screening over four years, two promising mutants for high dry flower yield and pyrethrins content, namely 7 (40 Gy-5), and 10 (40GY-8) were isolated. Conclusions The mutagenesis changed traits mean in positive or negative directions. Pyrethrum plant is highly sensitive to gamma irradiation and produced a high range of variability in the qualitative and quantitative traits. The mutagenesis changed the mean of traits in both positive and negative directions. Due to mutagenic efficacy, two mutants 7 (40 Gy-5), and 10 (40GY-8) were expressed high performance for pyrethrin percent i.e., 87.23 and 59.78% improvement over the check variety ‘Avadh’, with synchronous flowering. These two mutants are in the pipeline for release as a variety for cultivation in the North Indian plains.

INVESTIGATION OF SUPER ABSORBENT POLYMERS AND ZINC SULFATE ON THE YIELD AND YIELD COMPONENTS OF Calendula officinalis L.

Calendula officinalis L. is one of the most valuable medicinal plants of Asteraceae family and is widely used in the pharmaceutical, health, and food industries. To evaluate the effect of different treatments of super absorbent and zinc sulfate fertilizer on the yield and yield components of Calendula officinalis L., this experiment was conducted at the Islamic Azad University of Khoy. This was a factorial experiment using as the first factor super absorbent polymers at four levels to the soil (0, 4, 6, 8 g/kg) and as the second factor, 4 zinc sulfate concentrations of 0, 25, 50, and 70 mg per pot (based on a randomized complete block design with three replications). The results showed that super absorbent polymers had significant effect on all yield traits, but Zn sulfate fertilizer had only a significant effect on flower diameter, number of stems, total biomass with seeds, total biomass yield, seed yield, and harvest index. The interaction of the super absorbent polymers and zinc sulfate fertilizer increased the plant height, total biomass with seeds and flowers, seed weight, and flower and seed harvest index, whereas the diameter of flowers, number of stems, dry flower yield, flower number per m2, and seed yield were not affected. Super absorbent polymers with zinc sulfate fertilizer had the greatest effect on most yield traits and had a positive effect on increasing the yield components of Calendula officinalis L., which improved the grain yield. The use of super absorbent polymers can improve the water holding capacity of the soil, which reduces the need for water and improves the yield in arid and semi-arid areas.

Proizvodni potencijal i ekonomska održivost proizvodnje hrvatskih ekotipova buhača

Croatia is pyrethrums original growing zone and among rare places in the world where wild populations are found intact in nature. The aim of the research was to explore a production potential of Croatian wild pyrethrum ecotypes, and its use in breeding programs. Three wild ecotypes were tested for vegetative and yield parameters and a comparison between financial production parameters in Croatia and Slovakia was made. Plant height, number of flowers per plant, lodging, fresh and dry flower yield were not affected by ecotype in productive seasons (second and third). However, ecotypes differed in plant diameter and mass of 100 flowers. Positive linear regression among plant height, plant diameter, and number of flowers per plant with yield was found, but these traits did not correlate with lodging. Even though we found no significant difference between ecotype yields, financial analysis revealed the difference between ecotype profitability. Positive financial result was obtained in third season of growing with ecotypes 2 and 3. High costs of labour could be the main constraint in commercial pyrethrum production. Tested wild ecotypes, showed good productive characteristics and profitability potential, but there is a need for high yield breeding, and selection for traits adjusted to use of agro-mechanization.

Brassinosteroid Uygulamalarının Munstead Lavander Çeşidinde Bitki Gelişimi ile Sekonder Metabolit Üretimi Üzerine Etkileri

Bu araştırma steroid yapıda bir büyümeyi düzenleyici olan 24-epibrassinolid (24-eBL)‘in Lavandula angustifolia türüne ait “Munstead” lavander çeşidinde bitki gelişimi, uçucu yağ verimi ve bileşenleri ile toplam fenolik madde miktarları üzerine olan etkilerini belirlemek amacıyla gerçekleştirilmiştir. Bu amaçla bitkilere tomurcuklanma başlangıcında ve ilk uygulamadan 10 gün sonra olmak üzere iki kez 4 farklı konsantrasyonda (0, 0,75, 1,50 ve 2,25 mg/l) 24-eBL uygulanmıştır. Tam çiçeklenme döneminde hasat edilen bitkiler, taze ve kuru saplı çiçek verimi, kuru sapsız çiçek verimi, toplam fenolik madde miktarı ile uçucu yağ verimi ve bileşenleri bakımından değerlendirilmişlerdir. Araştırma sonucunda 0,75 ve 1,50 mg/l konsantrasyonlarında uygulanan 24-eBL‘nin sapsız kuru çiçek verimi, toplam fenolik madde miktarı ile bitki başına uçucu yağ verimini önemli ölçüde artırdığı belirlenmiştir. 24-eBL uygulamalarının uçucu yağ kompozisyonunu da değiştirdiğinin belirlendiği araştırmada, lavanderde 24-eBL uygulamasının kuru çiçek verimi ile uçucu yağ ve fenolik madde miktarını artırmak için kullanılabilecek bir uygulama olduğu tespit edilmiştir.

تأثیر تنش خشکی و کودهای فسفر و روی بر صفات زراعی مورفولوژیکی و میزان اسانس بابونه آلمانی

Drought is one of the most important limiting factors of plants growth which limits about 25 percent of arable lands production over the world. To investigate the effect of drought stress and phosphorus and zinc fertilizer levels on the quantitative properties and essential oil content of German chamomile (Matricaria recutita cv. Gural), a split plot factorial experiment was conducted in a randomized complete block design with three replications at Research Farm of University of Zabol in 2013. Treatments consisted of three irrigation levels (75% (control), 50% (mild stress) and 25% of field capacity (severe stress)) as main plots, and factorial combinations of three triple superphosphate fertilizer CaH4P2O8 levels (0, 150, and 300 kg ha-1) and two zinc sulphate fertilizer ZnSO4(H2O) levels (0 and 30 kg ha-1) as sub plots. Some traits such as plant height, number of flowers per plant, flower diameter, fresh and dry flower yield, root length and essence yield were measured. The results showed that drought stress significantly reduced values for all morphological traits, except root length. However, no significant mild stress effect was observed for essential oil content. The application of 150 kg P fertilizer ha-1 and 30 kg Zn fertilizer ha-1 increased essential oil content and values for morphological traits. The application of high amount of P fertilizer (300 kg ha-1) had negative effects on chamomile yield. In general, the results of this experiment showed that the application of 150 kg P fertilizer ha-1 and 30 kg Zn fertilizer ha-1 under mild stress (50% of field capacity) can improve essential oil content in German chamomile.

Effects of different fertilizer sources on vegetative characteristics of pot marigold plant (Calendula officinalis L.)

Medicinal plants are one of very valuable resources in wide range of natural resources of Iran that it can have an important role in health. In order to investigate the effect of nitrogen fertilizer and zinc sulfate on vegetative characteristics of Calendula Officinalis, as factorial experiment based on randomized complete block design was carried out with three replications in Takestan, Iran during 2010-2011 cropping season. The experimental factors were consisted of nitrogen fertilizer (manure and urea) with 5 levels (0 tons of manure + 120 kg.ha-1urea, 10 tons of manure + 90 kg.ha -1 urea, 20 tons of manure + 60 kg.ha -1 urea, 30 tons of manure + 90 kg.ha -1 urea and 40 tons of manure + 0 kg.ha -1 urea) and zinc sulfate of 3 levels (no spraying, once spraying and twice spraying). The results showed that the effect of nitrogen fertilizer (manure and urea) and zinc sulfate was significant on number of stem sub, leaf dry weight, stem dry weight, capitulum dry weight and flower yield. The highest flower yield was obtained from 20 tons manure + 60 kg.ha-1 urea with the amount of 77.96 g.m-2. In the case of zinc Sulfate, was obtained the maximum yield flower with twice spraying, the amount of 78.05 g g.m-2, interaction between treatments had no significant effect on shoot weight and flower yield. The maximum flower yield was obtained from combination treatment of 20 tons of manure + 60 kg.ha -1 urea and twice spraying zinc to amount

Improving growth, flower yield, and water relations of snapdragon (Antirhinum majus L.) plants grown under well-watered and water-stress conditions using arbuscular mycorrhizal fungi

The influence of arbuscular mycorrhizal (AM) fungus Glomus deserticola (Trappe and John) on plant growth, nutrition, flower yield, water relations, chlorophyll (Chl) contents and water-use efficiency (WUE) of snapdragon (Antirhinum majus cv. butterfly) plants were studied in potted culture under well-watered (WW) and water-stress (WS) conditions. The imposed water stress condition significantly reduced all growth parameters, nutrient contents, flower yield, water relations, and Chl pigment content and increased the electrolyte leakage of the plants comparing to those of nonstressed plants. Regardless of the WS level, the mycorrhizal snapdragon plants had significantly higher shoot and root dry mass (DM), WUE, flower yield, nutrient (P, N, K, Mg, and Ca) and Chl contents than those nonmycorrhizal plants grown both under WW or WS conditions. Under WS conditions, the AM colonization had greatly improved the leaf water potential (Ψw), leaf relative water content (RWC) and reduced the leaf electrolyte leakage (EL) of the plants. Although the WS conditions had markedly increased the proline content of the leaves, this increase was significantly higher in nonmycorrhizal than in mycorrhizal plants. This suggests that AM colonization enhances the host plant WS tolerance. Values of benefit and potential dry matter for AM-root associations were highest when plants were stressed and reduced under WW conditions. As a result, the snapdragon plants showed a high degree of dependency on AM fungi which improve plant growth, flower yield, water relations particularly under WS conditions, and these improvements were increased as WS level had increased. This study confirms that AM colonization can mitigate the deleterious effect of water stress on growth and flower yield of the snapdragon ornamental plant.