Journal of Ecological Engineering Volume 16, Issue 2, Apr. 2015, pages 136–142 DOI: 10.12911/22998993/1868 Research Article COMPARISON OF MORPHOLOGICAL TRAITS AND MINERAL CONTENT IN EUCOMIS AUTUMNALIS (MILL.) CHITT. PLANTS OBTAINED FROM BULBS TREATED WITH FUNGICIDES AND COATED WITH NATURAL POLYSACCHARIDES Piotr Salachna1, Agnieszka Zawadzińska1 1 Department of Horticulture, Faculty of Environmental, Management and Agriculture, West Pomeranian University of Technology in Szczecin, Papieża Pawła VI 3, 71-459 Szczecin, Poland, e-mail: piotr.salachna@zut. edu.pl; [email protected] Received: 2014.12.24 ABSTRACT Accepted: 2015.02.04 Eucomis autumnalis is an attractive ornamental species from the South Africa, com- Published: 2015.04.01 monly used in natural medicine. Plant protection programs, particularly those con- cerning plants grown for phytotherapeutics, are focused on prophylactic treatments that facilitate a limited use of pesticides negatively affecting the environment. Poly- saccharides, such as chitosan and sodium alginate are exemplary non-toxic and biode- gradable substances used for hydrogel coatings. The aim of this study was to investi- gate the effects of treating E. autumnalis bulbs with fungicide or coating with natural polysaccharides on the morphological traits and content of minerals in the leaves and bulbs. Prior to planting, the bulbs were divided into three groups: (I) untreated bulbs (control); (II) bulbs treated with Kaptan and Topsin fungicides; (III) bulbs coated with oligochitosan and sodium alginate. Bulb coating was found to exert a stimulating ef- fect on plant height, number and length of leaf, greenness index (SPAD), number of flowers per inflorescence, fresh weight of the aboveground part and fresh weight of bulbs. The leaves and bulbs of plants grown from coated bulbs contained more nitro- gen, potassium and boron. Treating the bulbs with fungicides positively affected the number of leaves, greenness index and fresh weight of the aboveground part. Keywords: pineapple lily, oligochitosan, sodium alginate, macronutrients, micronutrients. INTRODUCTION stimulate seed germination [4], accelerate flow- ering [5], increase chlorophyll content [6], and Synthetic fungicides used in plant protec- plant tolerance to stress [7], and improve yield tion have a negative impact on the environment, quantity and quality [8]. Another natural polymer and therefore, environmentally-friendly solutions that can be potentially used in plant cultivation is based on non-toxic and biodegradable substances sodium alginate. It is composed of β-1,4 linked are sought for. Some examples of environmental- β-D-mannuronic acid and α-L-guluronic acid. On ly-safe compounds are natural polysaccharides, of the industrial scale, alginates are extracted from which chitosan and its derivatives are particularly brown algae, mainly Laminaria and Lessonia [9]. promising [1]. Chitosan is a polymer obtained Sodium alginate, particularly in the form of depo- by N-deacetylation of natural chitin. It is a linear lymerized oligosaccharide, was reported to have a polymer containing D-glucosamine (GlcN) and stimulating effect on the growth in several plants, N-acetyl-D-glucosamine (GlcNAc) molecules such as mint [10], fennel [11], and potato [12]. linked by β-1,4-glycosidic bonds [2]. It is used in Natural polysaccharides can be used for coating agriculture and horticulture, mainly as an elicitor formation on the surface of plant organs [13]. of resistance to certain pathogenic infections and Eucomis autumnalis (Mill.) Chitt., also as a growth stimulator [3]. In plants, chitosan can known as “pineapple lily”, is an original bulbous 136 Journal of Ecological Engineering vol. 16(2), 2015 plant of Asparagaceae family, native to southern 60×40×19 cm, filled with deacidified peat (Kro- Africa. The plants have very decorative raceme nen, Poland), pH 6.0, with mean content of mac- -3 inflorescences composed of numerous, star- ronutrients amounting to 11 mg∙dm N-NO3, shaped, greenish-white and sweetly scented flow- 39 mg∙dm-3 P, and 13 mg∙dm-3 K. The substrate ers. This species can be grown as garden plants, was supplemented with multicomponent fertil- cut flowers and flowering potted plants, with high izer Hydrocomplex (Yara International ASA, demand by the European and North American Norway) at a dose of 5 g·dm-3 that contained markets [14]. Due to antibacterial and antifungal 12% N, 11% P2O5, 18% K2O, 2.7% MgO, 8% S, compounds, the bulbs of E. autumnalis are used 0.015% B, 0.2% Fe, 0.02% Mn, and 0.02% Zn. in southern African traditional medicine [15]. The Each box contained 8 bulbs, planted at a spacing of anti-inflammatory activity in E. autumnalis plant 10×10 cm. The plants were grown in an unheated depends on age, season, fertilization and growth plastic tunnel, under natural photoperiod. Air conditions [16]. The subject literature lacks data temperature was controlled with vents that were on E. autumnalis cultivation in the Central Eu- opened when the temperature exceeded 20 °C. ropean climatic conditions, which is a problem The plants were cultivated according to agro- for the producers of ornamental and medicinal technical standards developed for Eucomis by plants interested in wider use of this species. So the International Flower Bulb Centre [19]. When far, no information has been published on the use the plants reached the full bloom stage, the fol- of natural polysaccharides for encapsulation of lowing parameters were evaluated: plant height, E. autumnalis bulbs before planting. Therefore, leaf number and length, inflorescence length, and the aim of this study was to evaluate growth, de- number of flowers per inflorescence. Leaf green- velopment and the content of minerals in E. au- ness index that highly correlates with chlorophyll tumnalis plants grown from the bulbs treated with content was determined using Chlorophyll Meter traditional fungicides and from the bulbs coated SPAD-502 (Minolta, Japan). This evaluation is with oligochitosan and sodium alginate. based on determining the quotient of difference in light absorption by a leaf at 650 nm and 940 nm. The result is given in dimensionless units MATERIAL AND METHODS called SPAD. Mean SPAD value was calculated based on four readings of four leaves from each Plant material and treatments plant. The plants were dug out in both years of th The study was conducted at a research plot of the study on 20 October and the aboveground the West Pomeranian University of Technology in part and bulbs were weighted. Szczecin (53°25’ N, 14°32’ E; 25 m asl.). Study material were E. autumnalis bulbs, 14–16 cm in Determination of mineral content circumference, obtained from Dutch plantations. Prior to planting, the bulbs were divided into three The content of macro- and micronutrients groups: (I) non-treated control bulbs; (II) bulbs in the bulbs and leaves obtained at full anthesis treated for 30 min with fungicide suspension 1.0% was analyzed in a laboratory. To this end, 8 plants (w/v) Kaptan 50 WP (active ingredient: Captan) from each variant were randomly dug out, and the and 0.7% (w/v) Topsin M 500 SC (active ingre- maternal bulbs without roots and fully developed dient: thiophanate-methyl); (III) bulbs coated as leaf blades were separated. Chemical analyzes described by Startek et al. [17] in 0.2% (w/v) oli- were carried out in dried at 105 °C material, ac- gochitosan and 1% (w/v) sodium alginate (Sigma cording to the standards of an accredited labo- -1 ratory of the Chemical and Agricultural Station Aldrich). Oligochitosan (Mw 48 000 g∙mol ; DD 85%) was purchased from Center of Bioimmobili- in Szczecin. The mineralized plant material was sation and Innovative Packaging Materials (Szc- used for the determination of nitrate nitrogen by zecin, Poland). The products have been obtained means of a colorimetric method, potassium and using the free radical degradation process [18]. calcium by means of the atomic emission spec- trometry (Solaar S AA spectrometer), phosphorus Growth conditions and plant measurements content was evaluated based on Baton method on Marcel s 330 PRO spectrophotometer at a wave- The bulbs were planted on 15th April 2012 length λ = 470 nm, and magnesium and micronu- and 17th April 2013, into polyethylene boxes trient (B, Cu, Fe, Mn, Zn) content were measured 137 Journal of Ecological Engineering vol. 16(2), 2015 by means of the flame atomic absorption spec- suggested that chitosan stimulates the vegetative troscopy using Solaar S AA spectrometer [20]. growth and the developing of roots and shoots and improves the efficiency of nutrient and water Statistical analysis uptake, which can be beneficial for plant growth [21, 22]. Apart from oligochitosan, the coatings The study was designed as a univariate ex- investigated in our study included also sodium periment involving randomized sub-blocks, with alginate, which is another biostimulator exerting four replications comprising 8 plants each. The positive effects on plant metabolism. According results were verified statistically by means of to Khan et al. [23], treating opium poppy plants one-way analysis of variance (ANOVA), using (Papaver somniferum L.) with oligo-alginates at FR-ANALWAR software developed by Professor the doses of 0.02 to 0.1 mg·ml-1, improved root Franciszek Rudnicki of the University of Science and shoot length, dry weight, and total content of and Technology in Bydgoszcz. Significance of chlorophylls, carotenoids and alkaloids, including mean values variation was assessed by Tukey`s codeine and morphine. In fennel (Foeniculum vul- multiple comparison test at p = 0.05. gare Mill.), oligo-alginates positively affected the activity of nitrate reductase, plant growth and de- RESULTS AND DISCUSSION velopment, seed yield, and the content of assimila- tion pigments, proline and essential oils [24]. Statistical analysis of the experimental results The plants derived from the bulbs treated revealed that the treatment of E. autumnalis bulbs with a mixture of Kaptan and Topsin had signifi- before planting significantly affected most of the cantly more leaves, higher greenness index and evaluated traits (Table 1).