Helianthus Annuus Plants Research Articles

Investigating Removal of Carbamazepine by Helianthus annuus Plant Cells

Investigating Removal of Carbamazepine by Helianthus annuus Plant Cells

The Impact of Cannabis sativa and Helianthus annuus Plants on Honey bee Colonies (Apis mellifera L.): Varroa destructor Infestation and Performances

The performance and Varroa destructor infestation percentage of the honey bee colonies placed in areas with Cannabis sativa and Helianthus annuus plants were investigated. The study was conducted in the Havza district of Samsun and Samsun Ondokuz Mayıs University campus. A total of 15 bee colonies, with five in three different areas, were used. No chemical treatment against Varroa was administered in the colonies. In various areas, significant differences were observed in the worker bee population, the brood production, and the Varroa destructor infestation on adult bees and pupal cells. It is determined that the amount of Varroa on adult bees of the colonies in the sunflower and campus areas three and two times higher when compared to the colonies in cannabis area. Sunflower plants had a significantly positive impact on colony development. Cannabis has significantly increased brood production at the end of summer and autumn, which is a very critical period for honey bees. The campus area had significant disadvantages due to a summer drought and lack of flora at the beginning of autumn. It has been concluded that cannabis and sunflower plants play an important role in supporting bees before winter. It is essential to examine the efficacy of pure extracts derived from cannabis in combating Varroa through clinical research.

Effective paracetamol sensor activity, thermal barrier coating (TBC), and UV-light-driven photocatalytic studies of ZrxO2:Mg2+(1−x) nanoparticles

Herein, we report the synthesis of magnesia co-stabilized zirconia (ZrO2:Mg2+) NPs by a green (Helianthus annuus plant leaves extract) combustion route and their tailored characteristics for thermal barrier coating (TBC) applications.

Lead tolerance, accumulation and translocation in two Asteraceae plants: Limbarda crithmoides and Helianthus annuus

• Limbarda crithmoides L. and helianthus annuus L. plants morphology has not been affected under effect of lead (Pb) with the exception of height reduction in some Pb applied concentrations. • According to the metal tolerance index, limbarda crithmoides was more tolerant to Pb induced stress than helianthus annuus . • High levels of Pb were detected in the above-ground parts. • The concentrations of the accumulated Pb were higher in the roots of limbarda crithmoides and helianthus than in the shoots of these species. Lead (Pb) is known as a toxic metal and a non-essential element for plant metabolism and growth. This work investigated the phytotoxicity of Pb induced stress and assessed the accumulation potential of Pb in two Asteraceae plants; Limbarda crithmoides and Helianthus annuus. The experiments were performed for 45 days using different concentrations of Pb (0, 100, 200, 300 and 500 µmol.L –1 ). The dry biomass production in shoots and roots of Limbarda crithmoides were significantly enhanced with the increase of Pb doses in the growth medium, Helianthus annuus plants showed a modest variation in shoot and root dry weights, but without any significant difference as compared to the untreated plants. In addition, metal tolerance index values determined in the shoots and roots of these two species followed a similar trend as the dry weight contents. Both phenolic compounds and flavonoids were significantly increased in the two Pb treated species in comparison to the untreated plants (except flavonoid content of Limbarda crithmoides roots). Total inorganic nitrogen and macronutrient uptake were also assessed, and the two species showed different behaviour when varying Pb concentrations. Moreover, the two species accumulated Pb in their roots more than in the shoots (less than 1000 µg.g –1 DW) with a low translocation from roots into shoots (translocation factor < 1). Our findings demonstrated that both Limbarda crithmoides and Helianthus annuus were tolerant to Pb stress; nonetheless, the two species could not be classified as Pb hyperaccumulators.

Allometric deviation in biomass and biochemicals of sunflower (Helianthus annuus) plants amplified by lemongrass (Cymbopogon citratus) foliar extract

Allometric deviation in biomass and biochemicals of sunflower (Helianthus annuus) plants amplified by lemongrass (Cymbopogon citratus) foliar extract

Оценка фертильности пыльцы гибридов подсолнечника методом сплит-опыления

The main objective of the study was to study the effect of pollen from sunflower hybrids on the real seed productivity and setting of achenes in CMS-tester plants as the final indicators of pollen fertility. The studies were carried out in 2019 and 2021 at V.S. Pusotvoit All-Russian Research Institute of Oil Crops, Krasnodar. The object of the study was cultivated sunflower plants of Helianthus annuus L.: Oksi and NK Brio hybrids as paternal forms, as well as the sterile hybrid Kubansky 93 and the line VK1-klp A as CMS testers. On one vertical part of a separate head, the pollen of the Oksi hybrid was applied, and on the other, the pollen of the NK Brio hybrid was used, i.e. we applied the split-pollination method. The number of fiiled seeds on the head of the CMS tester when pollinated with the pollen of the hybrid Oksi was significantly less than that of the standard hybrid NK Brio. On average, over two years, a decrease in real seed productivity was observed in the hybrid Oksi by 1.97 times in relation to the hybrid NK Brio. The development of a larger number of achenes to technical maturity led to the progressive growth of a part of the head pollinated by the pollen of the NK Brio hybrid. A similar pattern was also noted for the seed set. On the heads of the CMS-tester, on average for two years, the pollen of the hybrid Oksi showed a significant decrease in the setting of achenes in relation to the standard – by 2.24 times. Our earlier data on the presence of morphological anomalies in the pollen of the Oksi sunflower hybrid are consistent with the facts of reduced seed productivity and seed set when evaluating the pollen quality of this hybrid crossed with the CMS-tester, established in this work. The question remains open at what stages the negative impact of the genetic factors of the reproductive function of the pollen of the Oksi hybrid occurs: pre- or post-zygotic.

Assessment of Tolerance to Lanthanum and Cerium in Helianthus Annuus Plant: Effect on Growth, Mineral Nutrition, and Secondary Metabolism.

Rare earth elements (REEs) present a group of nonessential metals for the growth and development of plants. At high concentrations, they can induce internal stress and disturb the physiological and biochemical mechanisms in plants. The potential uptake of lanthanum (La) and cerium (Ce) by the horticultural plant Helianthus annuus and the effect of these elements on its growth, its absorption of macroelements, and the contents of phenolic compounds and flavonoids were assessed. The plants were exposed to 0, 1, 2.5, 5, and 10 µM of La and Ce for 14 days. The results showed a remarkable accumulation of the two REEs, especially in the roots, which was found to be positively correlated with the total phenolic compound and flavonoid content in the plant shoots and roots. The plant’s growth parameter patterns (such as dry weight and water content); the levels of potassium, calcium, and magnesium; and the tolerance index varied with the concentrations of the two studied elements. According to the tolerance index values, H. annuus had more affinity to La than to Ce. Although these metals were accumulated in H. annuus tissues, this Asteraceae plant cannot be considered as a hyperaccumulator species of these two REEs, since the obtained REE content in the plant’s upper parts was less than 1000 mg·Kg−1 DW.

Molecular Interactions Associated with Coagulation of Organic Pollutants by 2S Albumin of Plant Proteins: A Computational Approach.

The removal of organic pollutants is a major challenge in wastewater treatment technologies. Coagulation by plant proteins is a promising technique for this purpose. The use of these proteins has been experimentally investigated and reported in the literature. However, the determination of the molecular interactions of these species is experimentally challenging and the computational approach offers a suitable alternative in gathering useful information for this system. The present study used a molecular dynamic simulation approach to predict the potentials of using Moringa oleifera (MO), Arachis hypogaea, Bertholletia excelsa, Brassica napus, and Helianthus annuus plant proteins for the coagulation of organic pollutants and the possible mechanisms of coagulation of these proteins. The results showed that the physicochemical and structural properties of the proteins are linked to their performance. Maximum coagulation of organic molecules to the proteins is between 50–100%. Among five proteins studied for coagulation, Brassica napus and Helianthus annuus performed better than the well-known MO protein. The amino acid residues interacting with the organic molecules play a significant role in the coagulation and this is peculiar with each plant protein. Hydrogen bond and π—interactions dominate throughout the protein–pollutants molecular interactions. The reusability of the proteins after coagulation derived from their structural quality analysis along with the complexes looks promising and most of them are better than that of the MO. The results showed that the seed proteins studied have good prediction potentials to be used for the coagulation of organic pollutants from the environment, as well as the insights into their molecular activities for bioremediation.

Modelling biophoton emission kinetics based on the initial intensity value in Helianthus annuus plants exposed to different types of stress

Biophoton radiation also referred to as ultra-weak photon emission (UPE) is used to denote a spontaneous and permanent photon emission associated with oxidative processes in cells and seems to universally occur in all living systems as a result of the generation of reactive oxygen species (ROS) that are produced under stress conditions. The measurement of this biophoton emission allows for a non-invasive approach in monitoring phenological stages throughout plant development which has direct relevance in agriculture research. In this study, the emission of photons emanating from sunflower (Helianthus annuus, L.) plants exposed to biotic and abiotic stress has been investigated. In healthy plants raised under controlled growth conditions UPE was low whereas in stressed individuals it considerably increased; particularly upon water stress. The kinetics of the signal is shown to reveal an exponential decay with characteristic dynamics, which appears to reflect different physiological states concomitantly setting in upon stress. The dynamics of the signal decay is shown to vary according to the type of stress applied (biotic vs. abiotic) hence suggesting a putative relationship between the kinetic traits of change in the signal intensity-decay and stress. Intriguingly, the determination of the change in the intensity of biophoton emission that ensued in a short time course was possible by using the initial biophoton emission intensity. The predictability level of the equations demonstrated the applicability of the model in a corroborative manner when employing it in independent UPE-measurements, thus permitting to forecast the intensity change in a very accurate way over a short time course. Our findings allow the notion that albeit stress confers complex and complicated changes on oxidative metabolism in biological systems, the employment of biophoton imaging offers a feasible method making it possible to monitor oxidative processes triggered by stress in a non-invasive and label-free way which has versatile applications especially in precision agriculture.

Пыльцевой анализ растений различных генотипов подсолнечника

Pollen analysis makes it possible to determine the reproductive potential of sunflower plants by the morphological characteristics of pollen grains with the aim of breeding to increase yields. The research was carried out in 2019–2020 at V.S. Pustovoit All-Russian Research Institute of Oil Crops, Krasnodar. The objects of the research were plants of cultivated sunflower Helianthus annuus L.: four hybrids – Factor, Typhoon, Oxy and NK Brio, confectionery variety Djinn, two parental lines of the hybrid Oxy – VK876 B and VK195, as well as a perennial wild growing hexaploid species H. tuberosus L. Pollen was stained with acetoorcein and viewed under a microscope Micros MS 20. The diameter of pollen grains in the hybrids Factor, NK Brio, Typhoon, Oxy, the line VK195 and the cultivar Djinn varied from 34 to 31 μm. The line VK876 B and H. tuberosus were characterized by the lowest values of this trait – 29 and 27 μm, respectively. For the line VK876 B and the hybrid Oxy, significant morphological heterogeneity of pollen was observed, which was expressed in a correspondingly high proportion of abnormal pollen grains – 34 and 26%. At the same time, there was a two-peak distribution of the values of the diameter of pollen grains. The morphological heterogeneity of the pollen grains of the hybrid Oxy is associated with the dominant inheritance of this trait from the maternal CMS-form VK876 A, since the paternal line VK195 has a normal characteristic of pollen grains. The pollen of the hybrid NK Brio showed a significantly higher (by 25%) seed setting in crossing with the CMS tester than that of the hybrid Oxy, which confirms the assumption that there is a relation between an increased proportion of abnormal pollen grains and reduced pollen fertility.

Avaliação da qualidade oleoquímica das sementes de gergelim (Sesamum indicum) e girassol (Helianthus annus)

Vegetable oils are extremely important for the human organism, being considered a source of energy and of fat-soluble vitamins (A, D, E and K), and fundamental in promoting the taste of food. Sunflower oil is obtained from the seed of the plant Helianthus annuus L., of the Compositae family, standing out for being the fourth oilseed in grain production and the fifth in cultivated area in the world. Another valuable seed used for oil extraction is sesame (Sesamum indicum, L.), which belongs to the Pedaliaceae family. Due to the quality and characteristics of some vegetable oils, which may change after long periods of storage, thus giving relevance to studies on the determination of these changes. From this, this work had the objective of evaluating the quality of the sesame and sunflower oil, commercial and cold extracted, to obtain more information about the alterations occurred during the storage period and its oxidative potential. The oleochemical analyzes were performed using the variables related to the iodine, peroxide, acidity and % free fatty acids (FFA) indices, where the analyzes were performed in triplicates. As a result, the commercialized sesame and sunflower oils showed values ​​above the limits recommended by the RDC No. 270, of September 22, 2005, in relation to the cold extracting sesame and sunflower oleochemical indexes presented adequate values. The contribution of the work developed shows that oils after extraction, industrial processing and depending on storage conditions can present vulnerability and compromise their quality.

Phytoremediation of zinc polluted soil using sunflower (Helianthus annuus L.)

This study aimed at assessing the ability of sunflower to remediate zinc (Zn) impacted soils and the partitioning factors of Zn in soil-plants interactions. The research method used ex situ experiments using teddy bear sunflower seeds with 8 different treatments for each. This began with the preparation of the sample soil media on garden soil, and the seeding of sunflower seeds. This research was carried out for six months starting in August - December 2020, with Helianthus annuus plants with variations of the Zn. Various concentrations of Zn were applied, ranging from 50 ppm to 350 ppm. Laboratory analysis of Zn was carried out using the Atomic Absorption Spectrophotometry (AAS) method. The research results have revealed that roots have the ability to translocate more Zn than shoots, which suggests a phytoremediation mechanism. Sunflower plants are able to translocate Zn, which proves it reliable for phytoremediation of Zn-polluted soil.

Cell wall composition and thickness affect mesophyll conductance to CO2 diffusion in Helianthus annuus under water deprivation.

Water deprivation affects photosynthesis, leaf anatomy, and cell wall composition. Although the former effects have been widely studied, little is known regarding those changes in cell wall major (cellulose, hemicelluloses, pectin, and lignin) and minor (cell wall-bound phenolics) compounds in plants acclimated to short- and long-term water deprivation and during recovery. In particular, how these cell wall changes impact anatomy and/or photosynthesis, specifically mesophyll conductance to CO2 diffusion (gm), has been scarcely studied. To induce changes in photosynthesis, cell wall composition and anatomy, Helianthus annuus plants were studied under five conditions: (i) control (i.e. without stress) (CL); (ii) long-term water deficit stress (LT); (iii) long-term water deficit stress with recovery (LT-Rec); (iv) short-term water deficit stress (ST); and (v) short-term water deficit stress with recovery (ST-Rec), resulting in a wide photosynthetic range (from 3.80 ± 1.05 μmol CO2 m-2 s-1 to 24.53 ± 0.42 μmol CO2 m-2 s-1). Short- and long-term water deprivation and recovery induced distinctive responses of the examined traits, evidencing a cell wall dynamic turnover during plants acclimation to each condition. In particular, we demonstrated for the first time how gm correlated negatively with lignin and cell wall-bound phenolics and how the (cellulose+hemicelloses)/pectin ratio was linked to cell wall thickness (Tcw) variations.

Genetic variability of some vegetative and flowering growth characteristics of multiflower mutant of Helianthus annuus L. plants

Abstract Present investigation was conducted to study the genetic variability of some growth and flowering traits of branching mutant of Helianthus annuus (sunflower) plants that having many inflorescences per plant. This study was done during two successive seasons at the Nursery of Ornamental Plants, Faculty of Agriculture, South Valley University, Qena, Egypt.High broad sense heritability with high genetic variance( GCV% and PCV%) were found for number of inflorescences per plant, stem diameter, leave area, fresh weight of vegetative growth and 100 seeds weight. This result refer to the small amount of environmental effects and these traits are under the influence of genetic control. While high heritability in broad sense with moderate genetic variance were found for plant height. Whereas moderate heritability in broad sense with moderate genetic variance were found for number of leaves per plant, inflorescence diameter, number of seeds per mean head. So, Selection is an expected tool to improve branching mutant of Helianthus annuus plant characteristics.

Various Parts of Helianthus annuus Plants as New Sources of Antimalarial Drugs.

Background Each part of H. annuus plants is traditionally used as medicinal remedies for several diseases, including malaria. Antimalarial activity of the leaf and the seed has already been observed; however, there is no report about antimalarial activity of the other parts of H. annuus plants. In this study, we assess in vitro and in vivo antimalarial activity of each part of the plants and its mechanism as antimalarial agent against inhibition of heme detoxification. Objective To investigate the antimalarial activity of various parts of H. annuus. Methods Various parts of the H. annuus plant were tested for in vitro antimalarial activity against Plasmodium falciparum 3D7 strain (chloroquine-sensitive), in vivo antimalarial activity against P. berghei using Peters' 4-day suppressive test in BALB/c mice, curative and prophylaxis assay, and inhibition of heme detoxification by evaluating β-hematin level. Results Ethanol extract of the roots showed the highest antimalarial activity, followed by ethanol extract of leaves, with IC50 values of 2.3 ± 1.4 and 4.3 ± 2.2 μg/mL, respectively and the percentage inhibition of P. berghei of 63.6 ± 8.0 and 59.3 ± 13.2 at a dose of 100 mg/kg, respectively. Ethanol extract of roots produced an ED50 value of 10.6 ± 0.2 mg/kg in the curative test and showed an inhibition of 79.2% at a dose of 400 mg/kg in the prophylactic assay. In inhibition of heme detoxification assay, root and leaf ethanol extracts yielded a lower IC50 value than positive (chloroquine) control with a value of 0.4 ± 0.0 and 0.5 ± 0.0 mg/mL, respectively. Conclusion There were promising results of the ethanol extracts of root of H. annuus as a new source for the development of a new plant-based antimalarial agent.

Influence of plant growth promoting rhizobacterial strains Paenibacillus sp. IITISM08, Bacillus sp. PRB77 and Bacillus sp. PRB101 using Helianthus annuus on degradation of endosulfan from contaminated soil

Endosulfan is a broad spectrum insecticide used in agriculture for protection of various food and non-food crops. It is persistent in nature and hence found in soil, air and water. The potential use of plants and microorganisms for the removal of endosulfan from soil was studied. Helianthus annuus plant was grown in soil spiked with 5, 10, 25 and 50 mg kg−1 concentrations of endosulfan and inoculated with plant growth promoting rhizobacterial strains Paenibacillus sp. IITISM08, Bacillus sp. PRB77 and Bacillus sp. PRB101 for 40, 80 and 120 days. Potential of plant for endosulfan uptake was evaluated by investigating the endosulfan levels in plant tissues (root and shoot). The results indicated that endosulfan accumulation followed the pattern of root > shoot as well as decrease in uptake of endosulfan in root and shoot of a plant grown in bacterial inoculated soil as compared to un-inoculated soil. Bacterial inoculation had a positive effect on endosulfan degradation. Maximum degradation of 92% at 5 mg kg−1 of endosulfan in soil was observed on inoculation with PRB101 after 120 days of inoculation. The results showed that plant growth promoting bacteria enhances plant biomass production. Lipid peroxidation was also estimated by determining the malondialdehyde (MDA) production, which is a biomarker of oxidative damage. Decrease in MDA formation by root and leaves of plants grown in the bacteria inoculated plant was also observed. The results suggested the effectiveness of plant growth promoting rhizobacteria to boost accumulation potential, biomass production and enhance remediation of endosulfan contaminated soil.

Diaporthe novem isolated from sunflower (Helianthus annuus) and other crop and weed hosts in Australia

In 2011, patches of lodged plants of Helianthus annuus (commercial sunflower) with stem lesions were observed in a commercial crop at Kingsthorpe, Queensland, Australia. Several species of Diaporthe were consistently isolated from the lesions. Diaporthe novem was identified by DNA sequence analysis. In following surveys, Diaporthe novem was found to be associated with other crop species including Cicer arietinum (chickpea), Glycine max (soybean), Lupinus alba (lupin), Sorghum bicolor (sorghum) Vicia faba (faba bean) and Vigna radiata (mungbean), and with the weed species Datura stramonium (common thornapple), Helianthus annuus (wild-type sunflower), Malva parviflora (small flowered mallow), Rapistrum rugosum (turnip weed), Sambucus gaudichaudiana (wild elderberry), Sisymbrium orientale (indian hedge mustard), Sonchus oleraceus (sowthistle), Verbena sp., Vicia sativa (common vetch), and Xanthium strumarium (noogoora burr). In pathogenicity tests, isolates of D. novem from sunflower were highly virulent when re-inoculated on commercial sunflower varieties. This study has identified D. novem as a frequent cause of stem canker of sunflower in the eastern cropping areas of Australia, and extends the known host range of D. novem.

Overcoming limitation of “recalcitrant areas” to phytoextraction process: The synergistic effects of exogenous cytokinins and nitrogen treatments

The aim of the present work was to test the efficiency of the phytoextraction process involving the use of exogenous phytohormone (cytokinins, CKs) and fertilizer (nitrogen, N) treatments in phytotechnologies to address risk management in “recalcitrant areas”. The CKs and N treatments, alone or combined (CKs + N) in a Modulated Application (MA), were tested on the crop plant Helianthus annuus, common to Mediterranean area, fast growing and with high biomass production. Plants were grown on boron (B) contaminated sediments (collected from a geothermal area located in Tuscany (Italy). Plant growth, B uptake, together with plant stress parameters were investigated. Boron is easily taken up and translocated by some crop plants, but the high phytotoxicity can dramatically impact the plant growth and consequently the applicability and efficiency of the phytoextraction process. As indicators of plant stress, oxidative balance and photosynthetic parameters were investigated to give a deeper insight of phytotoxic mechanisms. Results showed that while each treatment (CKs and N alone) had significantly positive effects on plant health, the MA treatment provided a synergistic effect on morphological parameters and biomass production as a whole. After MA treatment, plants showed antioxidant activity comparable to that of the control (unpolluted sediments) and showed an increase of net photosynthesis. Moreover, our data showed very high values of B uptake and translocation (about 800 mg kg−1 in shoots), without any alteration triggered by the treatments (CKs and N alone or combined in MA). B phytoextraction resulted increased about fivefold with the MA treatments, while each treatment alone increased only two or three folds when treated with either CKs or N. The MA treatment is not “contaminant specific”, so it could be applied in other “recalcitrant areas” where different types of contaminations occur, in order to overcome limitations of plant growth.

Osmotic and Salt Stresses Modulate Spontaneous and Glutamate-Induced Action Potentials and Distinguish between Growth and Circumnutation in Helianthus annuus Seedlings.

Action potentials (APs), i.e., long-distance electrical signals, and circumnutations (CN), i.e., endogenous plant organ movements, are shaped by ion fluxes and content in excitable and motor tissues. The appearance of APs and CN as well as growth parameters in seedlings and 3-week old plants of Helianthus annuus treated with osmotic and salt stress (0–500 mOsm) were studied. Time-lapse photography and extracellular measurements of electrical potential changes were performed. The hypocotyl length was strongly reduced by the osmotic and salt stress. CN intensity declined due to the osmotic but not salt stress. The period of CN in mild salt stress was similar to the control (~164 min) and increased to more than 200 min in osmotic stress. In sunflower seedlings growing in a hydroponic medium, spontaneous APs (SAPs) propagating basipetally and acropetally with a velocity of 12–20 cm min−1 were observed. The number of SAPs increased 2–3 times (7–10 SAPs 24 h−1plant−1) in the mild salt stress (160 mOsm NaCl and KCl), compared to the control and strong salt stress (3–4 SAPs 24 h−1 plant−1 in the control and 300 mOsm KCl and NaCl). Glutamate-induced series of APs were inhibited in the strong salt stress-treated seedlings but not at the mild salt stress and osmotic stress. Additionally, in 3-week old plants, the injection of the hypo- or hyperosmotic solution at the base of the sunflower stem evoked series of APs (3–24 APs) transmitted along the stem. It has been shown that osmotic and salt stresses modulate differently hypocotyl growth and CN and have an effect on spontaneous and evoked APs in sunflower seedlings. We suggested that potassium, sodium, and chloride ions at stress concentrations in the nutrient medium modulate sunflower excitability and CN.

Cultivation of Helianthus annuus L. cv. Sunflower Sunspot Dwarf with silicon application

In recent years Brazil has been presenting a constant production of flowers and ornamental plants, with an increase in diversity, quantity and quality. As for the Sunflower ornamental dwarf, in addition to the production of vegetable oil, may be an alternative in floriculture. The objective of the present work was to verify the effect of the use of silicon doses in the production and development of chapters of the ornamental dwarf sunflower crop cultivated in a pot under protected environment. The experiment was conducted from seeds of the hybrid Helianthus annuus L. cv. Sunflower Sunspot Dwarf. The substrate used in the vessels was based on pinus bark with vermiculite, perlite and rooting. The seeds were seeded in trays of expanded polystyrene, and after germination were transplanted in polypropylene pots with 10 replicates, totaling 50 plants. The irrigation system used was the micro sprinkler and the recommended fertilization for the crop weekly. The application of silicon was performed weekly at doses 0,0 g L -1 (Witness); 0.5 g L -1 ; 1.0 g L -1 ; 1.5 g L -1 and 2.0 g L -1 . The evaluations of the agronomic parameters were: plant height, stem and inflorescence diameters. For the plant height variable, the control group had the highest growth. For stem diameter and inflorescence there was no significant difference between treatments. The weekly application frequency and the silicon doses did not result in significant differences in stem diameter and inflorescence parameters evaluated for the ornamental plant Helianthus annuus L. cv. Sunflower Sunspot Dwarf compared to the witness.