Gazania Rigens Research Articles

Correction: Saini et al. Inoculation with Mycorrhizal Fungi and Other Microbes to Improve the Morpho-Physiological and Floral Traits of Gazania rigens (L.) Gaertn. Agriculture 2019, 9, 51

The Agriculture Editorial Office wishes to make the following changes to the author’s paper [...]

Pollen morphological investigation of selected species of family Asteraceae from Pakistan by using light and scanning electron microscopy.

A light and scanning electron microscopy technique was conducted to investigate the palynological features of 19 species belonging to 15 genera of the family Asteraceae. The species under investigation yielded pollen in a range of shapes, including spheroidal, prolate, and subprolate. Trizoncolporate, Tricolporate, and Tetracolporate are the three types of pollen apertures observed in examined species. Except for Gazania rigens, which has reticulate ornamentation under SEM, the exine pattern in all studied species is echinate. The majority of the species had isopolar polarity, whereas some members were apolar and heteropolar. The quantitative parameters that are polar to equatorial diameter, P/E ratio, length of colpi, width of colpi, length of the spine, width of spine, and exine thickness was measured by using light microscopy. The Coreopsis tinctoria had the lowest mean polar 19.75 μm to mean equatorial diameter 18.25 μm while the Silybum marianum had the highest polar 44.7μm to equatorial 48.2μm value. The value for colpi length/width was highest in Cirsium arvensis and lowest in C. tinctoria, measuring 9.7/13.2μm and 2.7/4.7μm, respectively. The spine length varied from 0.5μm in Sonchus arvensis to 5.5μm in Calendula officinalis. Verbesina encelioides had the highest exine thickness measurement (3.3μm), whereas S. arvensis had the lowest (0.3μm). The pollen surface of Tagetes erectus, has the highest number (65) whereas the lowest spines number (20) is found in S. arvensis. A taxonomic key based on pollen traits is provided for quick identification of the species. Significant implications for the systematics of the Asteraceae family can be drawn from the reported pollen's quantitative and qualitative data. RESEARCH HIGHLIGHTS: SEM and LM technique was used to study the palynological features of pollen grains. Quantitative and qualitative pollen features of 19 species of family Asteraceae are described. Morphological traits of pollen grains are important for the systematics of family Asteraceae.

Effect of explant type (leaf, stem) and 2,4-D concentration on callus induction: influence of elicitor type (biotic, abiotic), elicitor concentration and elicitation time on biomass growth rate and costunolide biosynthesis in gazania (Gazania rigens) cell suspension cultures

Gazania rigens (L.) Gaertn. (Asteraceae) is a medicinal plant with high ornamental potential and use in landscaping. The therapeutic potential of sesquiterpene lactones (SLs) as plant natural products for pharmaceutical development has gained extensive interest with costunolide (chemical name: 6E,10E,11aR-6,10-dimethyl-3-methylidene-3a,4,5,8,9,11a-hexahydrocyclodeca[b]furan-2-one) used as a popular herbal remedy due to its anti-cancer, antioxidant, anti-inflammatory, anti-microbial, anti-allergic, and anti-diabetic activities, among others. In the present study, two explant types (leaf, stem) and four 2,4-dichlorophenoxy acetic acid (2,4-D) concentrations (0, 0.5, 1 and 2 mg/L) were tested for callusing potential. The results showed that stem explants treated with 1.5 mg/L 2,4-D exhibited higher callus induction percentage (90%) followed by leaf explants (80%) with 1 mg/L 2,4-D, after a 4-week period. Cell suspension cultures were established from friable callus obtained from stem explants following a sigmoid pattern of growth curve with a maximum fresh weight at 20 days of subculture and a minimum one at 5 days of subculture. In the following stage, the effects of elicitation of cell suspension cultures with either yeast extract (YE) or methyl jasmonate (MeJA), each applied in five concentrations (0, 100, 150, 200 and 250 mg/L) on cell growth (fresh and dry biomass) and costunolide accumulation were tested. After 20 days of culture, YE or MeJA suppressed cell growth as compared to the non-elicited cells, while costunolide accumulation was better enhanced under the effect of 150 mg/L MeJA followed by 200 mg/L YE, respectively. In the subsequent experiment conducted, the optimal concentration of the two elicitors (200 mg/L YE, 150 mg/L MeJA) was selected to investigate further elicitation time (0, 5, 10, 15 and 20 days). The results revealed that YE biotic elicitation stimulated cell growth and costunolide production, being maximum on day 20 for fresh biomass, on day 5 for dry biomass and on day 15 for the bioactive compound. Accordingly, cell growth parameters were maximized under the effect of abiotic elicitation with MeJA for 15 days, while highest costunolide content was achieved after 10 days. Overall, MeJA served as a better elicitor type than YE for biomass and costunolide production. Irrespective of elicitor type, elicitor concentration and elicitation time, maximal response was obtained with 150 mg/L MeJA for 10 days regarding costunolide accumulation (18.47 ppm) and 15 days for cell growth (fresh weight: 954 mg and dry weight: 76.3 mg). The application of elicitors can lead the large quantity of costunolide to encounter extensive range demand through marketable production without endangering of G. rigens.Graphical

INTRODUCTION TO THE COMPOSITAE – 3

INTRODUCTION TO THE COMPOSITAE – 3

Antioxidant and Organic Dye Removal Potential of Cu-Ni Bimetallic Nanoparticles Synthesized Using Gazania rigens Extract

Copper-nickel bimetallic nanoparticles (Cu-Ni BNPs) were fabricated using an eco-friendly green method of synthesis. An extract of synthesized Gazania rigens was used for the synthesis of BNPs followed by characterization employing different techniques including UV/Vis spectrophotometer, FTIR, XRD, and SEM. Spectrophotometric studies (UV-Vis and FTIR) confirmed the formation of bimetallic nanoparticles. The SEM studies indicated that the particle size ranged from 50 to 100 nm. Analysis of the BNPs by the XRD technique confirmed the presence of both Cu and Ni crystal structure. The synthesized nanoparticles were then tested for their catalytic potential for photoreduction of methylene blue dye in an aqueous medium and DPPH radical scavenging in a methanol medium. The BNPs were found to be efficient in the reduction of methylene blue dye as well as the scavenging of DPPH free radicals such that the MB dye was completely degraded in just 17 min at the maximum absorption of 660 nm. Therefore, it is concluded that Cu-Ni BNPs can be successfully synthesized using Gazania rigens extract with suitable size and potent catalytic and radical scavenging activities.

Effect of ascorbic and salicylic acids on growth and flowering of Gazania cv. Frosty Kiss Mixed

Abstract An experiment was conducted during the season 2018-2019 in the lath house to study the effect of foliar spray with Ascorbic Acid (AsA) and Salicylic Acid (SA) on vegetative and flowering growth traits of Gazania (Gazania rigens L.) cv. Frosty Kiss Mixed. The experiment was designed as a factorial experiment (3×3) in Randomized Complete Blocks Design (RCBD) with three replicates. Plants were sprayed with concentrations of 0, 100, and 200 mg L-1 of AsA, and 0, 150 and 300 mg L-1 of SA. Foliar spray with 200 mg L-1 of AsA was superior on increasing number of leaves (40.00), number of suckers (9.22), leaf area (2174.09 cm2), leaves dry weight (6.36 g), number of flowers (5.64), early of flowering date (97.22 days), flower fresh and dry weight (4.78 g) (0.51 g) respectively, while spray with a concentration of 100 mg L-1 led to increase flower diameter (6.37 cm) and flowering duration (10.85 days). Foliar spray with SA improved all vegetative and flowering traits. Treatment of 300 mg L-1 was the most significant effect in increasing number of leaves (39.56), leaf area (2182.06 cm2), leaves fresh weight (43.93 g), number of flowers (5.83), flower diameter (6.31 cm), early of flowering date (98.07 days), and flower dry weight (0.50 g). The interaction effect between the studied factors was significant in all studied traits. Treatment of AsA200×SA150 was the most effective and gave the best results in terms of number of suckers (9.11), dry weight of leaves (6.49 g), number of flowers (5.87), flower diameter (6.44 cm), flowering date (96.98 days), flowering duration (10.89 days).

Palynological investigation of selected species of family asteraceae using light and scanning electron microscopic techniques.

Palynological study on 11 species of family asteraceae, that is, Sonchus asper L., Gazania rigens L., Helianthus annus L., Dahlia pinnata Cav., Zinnia peruviana L., Tagetes erectus L., Glebionis coronaria L., Calendula officinale L., Osteospermum ecklonis L., Centaurea cyanus L. and Cosmos sulphureus Cav. was carried out in Islamia College University Campus. The light microscopy showed that pollens were oblate-sheroidal (C. cyanus), oblate (Z. peruviana), prolate-spheroidal (H. annuus, T. erectus, G. coronaria, C. officinale, O. ecklonis, C. sulphureus) and spheroidal (S. asper, G. rigens, D. pinnata) in shape. The pollen was trizonocolporate, tricolporate and echinolophate type, all pollens had echinate ornamentation except G. regins which had reticulate ornamentation under SEM. Maximum Pollens were isopolar and asymmetrical while some were apolar and radially symmetric. The P/E ratio was larger in G. rigens (45/47 μm), T. erectus (45/40 μm) and C. officinale (40/45 μm) while others had smaller P/E diameter. C. sulphureus had 6 μm thick exine when compared to other taxa. The larger number of spines/echini were found on the exine surface of H. annuus and S. asper and the distance between adjacent echini were 4-5 μm in C. cyanus and G. rigens than others which had distance equal to 1-3 μm, while pores were visible on pollen surface of C. cyanus, O. ecklonis, Z. peruviana, H. annuus and G. rigens under light microscope and were invisible on other pollen surfaces. The pollen of family asteraceae members was of stenopalynous type.

Bioregulators Can Improve Biomass Production, Photosynthetic Efficiency, and Ornamental Quality of Gazania rigens L.

Gazania rigens L. is a perennial herbaceous plant that belongs to the Asteraceae family, widely used as bedding or ornamental potted plants. The environmental and economic sustainability of ornamental production can be enhanced using environmentally friendly bioregulators. A pot experiment was conducted to evaluate the influence of key bioregulators gibberellic acid ((GA3) at 50, 100 or 150 mg L−1), humic acid ((HA) at 100, 300 or 600 mg L−1), and ascorbic acid ((AA) at 50, 100 or 200 mg L−1)), on the growth, leaf gas exchange, and ornamental quality of G. rigens. The results indicated that plants treated with foliar applications of GA3, HA, or AA exhibited higher plant fresh and dry biomass, plant height, leaf area, and leaf area ratio, root-shoot ratio, root-shoot mass fractions, and number of flowers, as well as the flowers display time. All bioregulator treatments enhanced the vegetative and floral characteristics of Gazania plants. The GA3 was the most efficient at the concentration of 100 mg L−1. The highest efficacy of HA and AA treatments was observed at the higher concentrations, 600 and 200 mg L−1, respectively. These results were associated with higher photosynthetic rate (A), transpiration rate (E) as well as stomatal conductance (gs), and water use efficiency (WUE). In conclusion, the results suggest that foliar-applied bioregulators to Gazania are promising and represent sustainable strategies to enhance growth, flowering, and flower display time of Gazania plants.

Arbuscular mycorrhiza, but not hydrogel, alleviates drought stress of ornamental plants in peat-based substrate

In a greenhouse study, we examined the application potential of symbiotic arbuscular mycorrhizal fungi (AMF) and water absorbing gel (hydrogel) in planting pot-grown ornamental plants that periodically experience drought stress. We tested the hypotheses that either of these treatments can improve plant growth and flowering under conditions of water deficiency. Three species of ornamental plants – Gazania rigens, Pelargonium peltatum and P. zonale – were grown in pots with peat-based substrate either inoculated or non-inoculated with commercial inoculum of AMF, and either with or without added hydrogel. Generous watering during the first 14 weeks ensured well-grown plants. In the next 15 weeks, plants either were well watered or were periodically exposed to moderate or strong drought stress to an initial wilting point or sufficient to cause strong wilting, respectively, before the substrate was again re-saturated with water. The three tested species differed in their resistance to drought stress, P. peltatum being the most resistant and G. rigens the most sensitive. Strong drought decreased shoot biomass of G. rigens and P. zonale, but it had no effect on shoot biomass of P. peltatum, that even increased flowering. As a response to drought, mycorrhizal colonization of plant roots intensified and AMF significantly increased shoot biomass (and several biometric parameters) of all plant species and promoted flowering of G. rigens and P. zonale under all watering regimes. AMF thus confirmed the hypothesized potential for promoting plant growth under drought. On the other hand, the addition of hydrogel brought no positive growth effect on any plant species. On the contrary, it decreased flowering of all plants and interacted negatively with AMF.

Inoculation with Mycorrhizal Fungi and Other Microbes to Improve the Morpho-Physiological and Floral Traits of Gazania rigens (L.) Gaertn

In the present analysis, we evaluated the effect of different microbial inoculants on growth and floral responses of Gazania rigens (L.) Gaertn. Two prevailing arbuscular mycorrhizal fungi (AMF) i.e., Funelliformis mosseae and Acaulospora laevis, along with Trichoderma viride and Pseudomonas fluorescens, were examined in a pot experiment. Independent roles of these four microbes and their different combinations were used in sixteen treatments of G. rigens. The experiment was conducted in a polyhouse with five replicates per treatment in a randomized complete block design. The results of microbial inoculants were very effective for growth yield and flowering response over the control. Early flowering was noted in the combination of F. mosseae, A. laevis and P. fluorescens, which also showed the best results for flower head size, flower fresh and dry weight, total chlorophyll, carotene and phosphorus content. Arbuscular mycorrhiza (AM) root colonization (%) and AM spore number were also the highest for the same treatment, whereas the number of leaves, number of buds and root length were maximum in the combined treatment (F. mosseae + A. laevis + T. viride + P. fluorescens). Overall, this study proposes that growers should consider microbial inoculants for the better yield and flower quality of G. rigens.

Comparative GC-MS Analysis of Nine Different Seasonal Flowers Growing in Selected Region of Pakistan

Seasonal flowers contribute in the attraction and fragrances of volatile compounds. These flowers volatiles also contribute in the protection of plants from different diseases. The current study was aimed to analyze and identify the flowers volatile from seasonal flowers grown in Hazara. For this purpose a comparative study of volatile compounds from aqueous fractions of nine different seasonal flowers in terms of qualitative and quantitative composition was done by gas chromatography-mass spectrometry (GC/MS). The mass spectrum of unknown compounds was identified by comparing the mass spectrum of known compounds using NIST 5 library search program and available standards library. Total 67 compounds were identified belongs to different classes of organic compounds i.e esters, fatty acyls, terpenoid, saponins, tannins, alkaloids, aldehydes, ketones and hydrocarbons. 10 compounds were identified in Veronica chamaedrys, 12 in Ligustrum sinense, 11 in Ixora coccinea, 11 in Gazania rigens, 11 in Ligustrum lucidum, 14 in Amaryllis belladonna, 8 in Plantago lanceolata, 15 in Rosa indica and 26 in Callistemon viminalis. The main compounds in nine different seasonal flowers were mono(2-ethylhexyl) phthalate, n-hexadecanoic acid, phytol, 6-octadecenoic acid, methyl ester, (Z)-, hexadecanoic acid, methyl ester, beta cubebene, caryophyllen, phenylethyl alcohol, 4H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl-, benzaldehyde, 2-hydroxy-4-methyl-, bicyclo[2.2,1]heptane-1 carboxylic acid, 7,7,dimethyl-2-oxo-, 2-furancarboxaldehyde, 5-(hydroxymethyl)-, γ.-sitosterol, methyl gallate, pyrogallol, α-linolenic acid, 11-octadecenoic acid, methyl ester, lupeol, 2-cyclopenten-1-one, 2-hydroxy-, 1,2-benzenediol, β.-sitosterol, octadecanoic acid, oleic acid, 9, 12-octadecadienoic acid (Z,Z)-, 1-heptacosanol, spirost-8-en-11-one, 3-hydroxy-, (3,14,20,22 β.,5. α, 25R)-, 2-cyclopenten-1-one, 2-hydroxy-, eucalyptol, spiro[4,5]decan-7-one,1,8-dimethyl-8,9-epoxy-4-isopropyl.. Some compounds were detected in all nine flowers such as mono (2-ethylhexyl) phthalate. The concentration of this compound was more in Veronica chamaedrys (28.851%) and on the other hand having fewer amounts in flower Ixora coccinea (0.218%) and some compounds identified only in one flower such as caryophyllene. Most of the compounds were present in all selected flower while there were also some unique compounds which were present in one flower while absent in other. It shows that specific properties of flower associated with these unique compounds. Similarly, identified compounds suggested their role in the field of medicines and pharmaceutical sciences which need further investigations.

Metabolomic profiling and anti-infective potential of Zinnia elegans and Gazania rigens (Family Asteraceae)

The present study evaluates the chemical composition of Zinnia elegans and Gazania rigens based on their metabolomic profiles using liquid chromatography coupled with high-resolution mass spectrometry (LC‐HR-MS), alongside with the anti-infective activities of their ethanol extracts, as well as, different fractions. A significant difference was observed between the LC-MS profiles of the two plants such as, coumarins, sesquiterpene lactones and phenylethanoids which were characteristic for Z. elegans, while amides and phenolic acid derivatives were characteristic for G. rigens. These results highlight the chemical potential of Z. elegans and G. rigens. Furthermore, the ethyl acetate fraction of Z. elegans showed a significant antimalarial activity with IC50 values of 21.03 and 13.72 µg/mL against Plasmodium falciparum D6 and P. falciparum W2, respectively.

Effects of Arbuscular Mycorrhizal Fungi on Gazania rigens Pot Plant Cultivation in a Mediterranean Environment

Herbaceous plants used in island beds and borders need to be rapid growing, high performing and maintaining good visual quality during the growing season. Arbuscular mycorrhizal (AM) fungi application is acquiring interest for its beneficial effects on ornamental bedding plants. Gazania rigens is a herbaceous ornamental plant grown for its large daisy-like flowers. The species thrives in the coastal areas of the Mediterranean region, particularly in the mild climate of southern Italy and Sicily, where performs well in summer bedding schemes in sea side gardens even in dry and windy conditions. The aim of this study was to evaluate the effect of inoculation with Rhizophagus irregularis on several ornamental parameters of Gazania rigens. Prior to transplanting, three-months-old plants received a mycorrhizal inoculum carrying 40 spores g-1 of Rhizophagus irregularis. Inoculum was applied at a rate of 10 g plant-1. The AM application significantly increased number of flowers per clump by 100% and number of flowers per plant by 124.0%. Rhizophagus irregularis also positively influenced number of leaves per plant, plant height, and roots dry weight. Our findings indicated that mycorrhizal inoculation with R. irregularis may be beneficial to nursery growers wishing to produce high quality gazania for spring-summer bedding plant schemes.

Ecophysiological responses of six coastal dune species along the eastern seaboard of South Africa

AbstractEcophysiological responses of six co‐occurring dune species were investigated in a field study to determine whether they exhibit similar functional traits in response to environmental stressors. The species included Brachylaena discolor DC, Chrysanthemoides monilifera (L.), Scaevola plumieri (L.) Vahl, Canavalia maritima (Aubl.) Thouars, Gazania rigens (L.) Gaertn. and Cyperus esculentis L. Carbon dioxide exchange was saturated at 1,800 μmol m−2 s−1 in S. plumieri and at 1,000–1,300 μmol m−2 s−1 in the others. Maximal CO2 exchange occurred during mid‐morning. Midday stomatal closure occurred in S. plumieri, C. monilifera and B. discolor, while stomatal regulation was achieved by maintaining low conductance. Photoinhibition was minimized by efficient mechanisms for light dissipation. Species such as S. plumieri, C. maritima and B. discolor exhibited sclerophylly, a trait for survival in saline and nutrient‐ and water‐deficient environments. Concentrations of Na+ and Cl−1 were high in C. monilifera, G. rigens, B. discolor and S. plumieri, while the high C:N ratio in S. plumieri and C. esculentis suggested nitrogen deficiency. The responses of the six species to environmental stressors in terms of light use, gas exchange, ion and water relations and degree of sclerophylly suggest similar strategies for survival in the dune environment.

Compost-based substrate for Gazania rigens (L.) cultivation

Compost-based substrate for <i>Gazania rigens</i> (L.) cultivation

The Influence of Silicon and Multinutrient Fertilizer On the Quality and Chemical Composition of Gazania Rigens ‘Kiss Yellow’, Salvia Farinacea ‘Fairy Queen’ and Verbena ‘Obsession Lilac’ Plants

Abstract Silicon supplementation may lead to positive changes in plant quality, including their appearance. The two-factorial experiment with three ornamental plant taxa Gazania rigens ‘Kiss Yellow’, Salvia farinacea ‘Fairy Queen’ and Verbena ‘Obsession Lilac’ was conducted in the years 2012-2013. The first factor was foliar application of Si in form of ortho-silicic acid stabilized with choline (YaraVita Actisil) at the concentrations of 60, 120 and 180 mg·dm-3, while the second was soil application of multinutrient fertilizer (Insol U) at the concentrations of 0.25% and 0.50%. Biometric measurements of plants were carried out at the beginning of flowering. The laboratory analyses included the determination of the content of P, K, Ca, Mg and Si as well as chlorophyll content in the leaves. Silicon had a beneficial influence on a majority of the analysed morphological features. Plants reacted best to high silicon doses (120 and 180 mg·dm-3). Particularly beneficial effects were noted with respect to improved flowering of all analysed plant taxa and to the vegetative development of Salvia and Gazania. Insol U supplementation noticeably improved the flowering of Verbena.

Identification of new plant hosts of 16SrII group phytoplasmas in Saudi Arabia

Qassim region is one of the main agricultural areas in Saudi Arabia. During 2015, ornamental, landscape and bindweed plants showing virescence; yellowing, phyllody, witches’ broom, proliferation, fasciation, short internode, and dieback symptoms were observed in this region. To confirm the presence of phytoplasmas, DNA extracted from symptomatic and asymptomatic plants was used to amplify 16S rRNA-encoding gene through direct and nested PCR assays using P1/P7, R16F2n/R16R2 and fU5/rU3 primers. Phytoplasma DNA was detected in all symptomatic plants collected. Sequencing and phylogenetic analysis were performed to identify the phytoplasmas detected. BLAST comparison indicated that the phytoplasmas showed more than 99.2% identity with phytoplasmas in 16SrII group. Three phytoplasma strains from Albizia and periwinkle shared 100% identity with ‘Candidatus Phytoplasma aurantifolia’, subgroup 16SrII-B, while phytoplasmas affecting Parkinsonia aculeate, Gazania rigens, Hibiscus rosa-sinensis, Calendula officinalis, Plectranthus scutellarioides, Convolvulus arvensis, Zinnia Magellan, Conocarpus lanceolatus and Catharanthus roseus were identical to papaya yellow crinkle, classified in the 16SrII-D subgroup.

Comparative DNA profiling, botanical identification and biological evaluation of Gazania longiscapa DC and Gazania rigens L.

Gazania longiscapa DC and Gazania rigens L. are species of cultivated ornamental plant that grow in Egypt. Genus Gazania has a role in folk medicine to prevent toothache; this study presents a comparative investigation of genetic and botanical features of root, rhizome, leaves and flowers of the two Gazania species and comparing their biological activity as analgesic and antiinflammatory as related to their folk medicinal use.The genetic and botanical differences between the two Gazania species are reported for the first time in this study. The results contribute toward validation of the traditional use of Gazania showing that both species are safe for oral administration and they exhibit significant antinociceptive and anti-inflammatory effects in a dose dependent manner.

Morpho-physiological and phytochemical traits of gazania (Gazania rigens) affected by foliar application of bio-stimulants

Background: Gazania (Gazania rigens), a member of the Asteraceae family, is an ornamental plant that is cultivated on a large scale in gardens and landscapes. Material and Methods: : This experiment was carried out to evaluate the effects of bio-stimulants compounds on morpho-physiological and phytochemical traits of gazania on the basis of randomized complete blocks designed (RCBD) with three replications. The treatments included biostimulants of aminolforte, kadostim, fosnutren, humiforte (each of them at 2 and 4 L.ha-1), and control treatment (foliar spray with distillated water). Results: The effects of treatments were significant (pN0.01) on all of the traits except for the number of leaves and capitula per plant, and capitula diameter. The maximum amount of the plant height and total dry weight was obtained in the treatment of kadostim at 2 L.ha-1. The largest collar diameter of the stem and total fresh weight was observed in the treatment of aminolforte at 4 L.ha-1. The greatest diameter of the flower and stem was observed in the treatment of aminolforte and fosnutren at 2 L.ha-1, respectively. Also, the highest quantity of SPAD value, chlorophylls a and b, and total chlorophyll, carotenoids, and nitrogen content were related to the foliar application of aminolforte at 4 L.ha-1, but the highest percentage of potassium content was attained in humiforte treatment at 4 L.ha-1. In comparison, the least amount of all traits was observed in control treatment. Conclusions: The findings showed that the foliar applications of bio-stimulants based on bio-active amino acid compounds with a mixture of nutrients have positive effects on the growth, morphophysiological, and phytochemical traits of the gazania.

CHARACTERIZATION OF NUTRIENT DISORDERS OF GAZANIA RIGENS 'DAYBREAK WHITE'

Gazania rigens ‘Daybreak White’ plants were grown in silica sand culture to induce and photograph symptoms of nutritional disorders. Plants were grown with a complete modified Hoagland’s all nitrate solution: (macronutrients in mM) 15 NO3-N, 1.0 PO4-P, 6.0 K, 5.0 Ca, 2.0 Mg, and 2.0 SO4-S, plus µM concentrations of micronutrients, 72 Fe, 18 Mn, 3 Cu, 3 Zn, 45 B, and 0.1 Mo. The treatments causing nutrient deficient symptoms were induced with a complete nutrient formula minus one of the nutrients. Boron toxicity was also induced by increasing the element 10× higher than the complete nutrient formula. Reagent grade chemicals and deionized water of 18-mega ohms purity were used to formulate treatment solutions. The plants were automatically irrigated. The solution drained from the bottom of the pot and was captured for reuse. A complete replacement of nutrient solutions was done weekly. Plants were monitored daily to document and photograph sequential series of symptoms as they developed. Typical symptomology of nutrient disorders and critical tissue concentrations are presented. Out of the thirteen treatments, eleven exhibited symptoms. Deficiency symptoms of N, S, and Ca were first to manifest. Should nutritional disorders arise growers should first consider these three problems when trying to determine the possible cause.