Piotr Salachna

EFFECT OF CHITOSAN ON PLANT GROWTH, FLOWERING AND CORMS YIELD OF POTTED

The research was aimed at determining the influence of chitosan with different mo lecular weights on the growth and yield of flowers and corms of ‘Gompey’ freesia cultivated in pots. Freesia corms were soaked for 20 minutes in 0.5% chitosan solutions with low molecular weight (2 kDa), medium molecular weight (50 kDa) and high molecular weight (970 kDa). The average deacetylation level of the chitosans used was 85%. The plants were cultivated under controlled conditions (18/16 °C day/ night, relative air humidity of 60%, quantum irradiance of 90 μmol∙m -2 ∙s -1 with a light/ dark cycle of 14/8 hours). The research results obtained have shown that chitosan is used as a biostimulator in the cultivation of potted freesia. Regardless of the molecular weight of the compound, the chitosan-treated plants had more leaves and shoots, flowered earlier, formed more flowers and corms . The application of medium- and high-molecular-weight chitosan resulted in higher plants with a higher relative chlorophyll content (SPAD). The highest increase in the corm weight was observed as a result of treating plants with high-molecular-weight chitosan. No chitosan influence on the length of the main inflorescence shoot or the inflorescence length was observed.

Effect of daminozide and flurprimidol on growth, flowering and bulb yield of Eucomis autumnalis (Mill.) Chitt.

Abstract Eucomis autumnalis (Mill.) Chitt., commonly known as pineapple lily, is a new ornamental pot plant with great marketing potential. This work evaluated the effects of two gibberellin synthesis inhibitors (daminozide and flurprimidol) applied as commercial plant growth regulators (PGRs) B-Nine and Topflor on the growth, flowering, and bulb yield in E. autumnalis. The PGRs were applied three times as substrate drenches or foliar sprays at the concentration of 15 mg dm-3 (flurprimidol) or 4250 mg dm-3 (daminozide). Plant growth was restricted only by flurprimidol, particularly when it was applied as substrate drenches. Plant height was reduced by 48% at anthesis and by 38% at flower senescence, compared to the untreated control. Regardless of the application method, flurprimidol increased the leaf greenness index (SPAD) and bulb weight. Daminozide treatments were ineffective in controlling plant height and negatively influenced bulb weight. Foliar sprays of daminozide increased the length of inflorescences and the number of flowers per inflorescence.

COMPARISON OF MORPHOLOGICAL TRAITS AND MINERAL CONTENT IN EUCOMIS AUTUMNALIS (MILL.) CHITT. PLANTS OBTAINED FROM BULBS TREATED WITH FUNGICIDES AND COATED WITH NATURAL POLYSACCHARIDES

Eucomis autumnalis is an attractive ornamental species from the South Africa, commonly used in natural medicine. Plant protection programs, particularly those concerning plants grown for phytotherapeutics, are focused on prophylactic treatments that facilitate a limited use of pesticides negatively affecting the environment. Polysaccharides, such as chitosan and sodium alginate are exemplary non-toxic and biodegradable substances used for hydrogel coatings. The aim of this study was to investigate 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 effect 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 nitrogen, potassium and boron. Treating the bulbs with fungicides positively affected the number of leaves, greenness index and fresh weight of the aboveground part.

EFFECTS OF SODIUM CHLORIDE ON GROWTH AND MINERAL NUTRITION OF PURPLETOP VERVAIN

There is a rising demand for salt-tolerant species for landscaping. Purpletop vervain is an excellent landscape plant for gardens and parks, with fragrant lavender to rosepurple flowers. However, little is known concerning the effect of sodium chloride on morphological characteristics, flowering and mineral uptake of purpletop vervain. In this study, carried out in 2013–2014, the plants of purpletop vervain were grown in pots in an unheated plastic tunnel. The plants were watered with 200 mM NaCl solution four times, every seven days. Salinity-exposed plants were characterized by slightly reduced plant height, weight of the aboveground part and visual score. Salt stress caused also an increase in leaf content sodium, chlorine and manganese. Salinity had no effect on earliness of flowering and content in leaves of phosphorus, potassium, magnesium, copper, zinc and iron. Purpletop vervain seems to be plant species able to tolerate salt stress under controlled conditions.

RESPONSE OF SPECKLED SPUR-FLOWER TO SALINITY STRESS AND SALICYLIC ACID TREATMENT

One of the limitations to using ornamental plants in green areas is too high salinity and alkalization of the soil. The adverse effect of salinity on plant growth and development may be effectively reduced by application of salicylic acid. Plectranthus ciliatus is an attractive bed plant with ornamental leaves, recommended for growing in containers, hanging baskets, or sunny borders. The aim of this study was to investigate the response of P. ciliatus to salicylic acid and calcium chloride. The plants were grown in pots in a glasshouse and were sprayed with solution of 0.5 mM salicylic acid and watered with 200 mM calcium chloride. The application of salicylic acid resulted in an increased weight of the aboveground parts, higher stomatal conductance and leaf greenness index and enhanced leaf content of nitrogen, potassium, iron and zinc. Salinity-exposed plants were characterized by reduced weight, stomatal conductance and leaf greenness index. Salt stress caused also a drop in leaf content of nitrogen, potassium and iron, and an increase in calcium, sodium, chlorine, copper and manganese concentration. Salicylic acid seemed to relieve salinity-mediated plant stress.

EFFECT OF SUBSTRATES CONTAINING COMPOSTS WITH THE PARTICIPATION OF MUNICIPAL SEWAGE SLUDGE ON FLOWERING AND MACRONUTRIENT CONTENT IN THE LEAVES OF GARDEN PANSY (Viola × wittrockiana Gams.)

The aim of the study was to assess the impact of substrates containing composts made from municipal sewage sludge and straw or sawdust on flowering, leaf greenness index and macronutrient content in the leaves of ‘Fancy Carmine with Blotch’ garden pansy. Two composts, with the following compositions: K I – 70% municipal sewage sludge, 30% rye straw; K II – 70% municipal sewage sludge, 30% coniferous tree sawdust, were used for the preparation of substrates. Six substrates of peat and compost at 25, 50 and 75% (by volume) were prepared. The control object was a peat substrate, pH 5.8–6.0, supplemented with Azofoska at 2.5 g·dm -3 . It has been found that leaf greenness index of pansy increased with an increasing share of compost. Composts involving municipal sewage sludge at the level of 50% had a more positive influence on the abundance of pansy flowering than at 25 and 75%. The content of to tal nitrogen, phosphorus, potassium and sulfur in the leaves increased with increasing the dose of compost. The content of total phosphorus in the leaves at the end of pansy cultivation in compost substrates ranged optimally for this species. In the experiment conducted in 2006, pansies contained more total nitrogen, potassium and sulfur than the flowering pansies planted in 2005.

Exopolysaccharide Gellan Gum and Derived Oligo-Gellan Enhance Growth and Antimicrobial Activity in Eucomis Plants

One of the visible trends in the cultivation of plants, particularly of medicinal ones, is the increasing interest of researchers in polysaccharides and their derivatives that show biostimulatory properties and are also safe to use. In the current study, we evaluated the effects of gellan gum and its depolymerized form oligo-gellan, on growth and antimicrobial activity of two ornamental species Eucomis bicolor and Eucomis comosa used in natural medicine. The biopolymers were applied in the form of bulb coating prepared by using polyelectrolyte complexes. In both species investigated, gellan gum and oligo-gellan enhanced the fresh weight of leaves and bulbs, the performance of the photosynthetic apparatus, and the leaf content of basic macronutrients. In comparison with the control, the plants treated with oligo-gellan accumulated more biomass, were first to flower, and had the highest leaf content of potassium. The extracts from the bulbs treated with gellan gum and oligo-gellan showed higher effectiveness in reducing the count of Bacillus atrophaeus, Escherichia coli, and Staphylococcus aureus than those from the bulbs not treated with the polysaccharides. The research described here largely expands our current knowledge on the effects of gellan gum derivatives and has a huge practical potential in agriculture production.

Sewage Sludge Compost as Potting Media Component for ivy Pelargonium (Pelargonium peltatum (L.) L’Her.) Production

The increasing demand and raising cost of high quality peat for horticultural use have led to search for low cost substrates as an alternative. The source of materials for their production can be various types of industrial, municipal and agricultural waste. Most of them are rich in organic matter and minerals essential for plant growth. The aim of the study was to evaluate the growth and flowering of two ivy pelargonium cultivars (‘Beach’ and ‘Boneta’) grown in the media containing sphagnum peat and composts made from municipal sewage sludge and structure-forming components. Two different types of composts were used, consisting in equal proportions of sewage sludge and straw (SSRS) or leaves (SSL). The composts replaced 25% or 12.5% of sphagnum peat (v/v) in the growth media. A control media was sphagnum peat (100%) supplemented with a mixed fertilizer. It was found that the media containing both types of compost might be useful for growing ivy pelargonium. The most beneficial effect on the growth, foliage, and a decorative value of the pelargonium was observed for the medium containing 12.5% of SSL compost and 87.5% of peat. Decorative value of the pelargonium grown in the medium with 25% of SSL compost or with either dose of SSRS compost, did not differ from the control plants. The investigated cultivars differed in the number of shoot, color and area of leaves as well as length of stem of inflorescence. ‘Boneta’ cv. developed more stems and had greener leaves than those from ’Beach’ cultivar. While cultivar ‘Beach’ had greater area of leaves per plant and longer stem of inflorescence.

Enhancing Growth in Eucomis autumnalis (Mill.) Chitt. Seedlings with Exogenous Application of Nitric Oxide

Abstract Nitric oxide (NO) is a molecule that regulates biological processes in plants and may be used in horticultural practice as a potential plant growth regulator. Eucomis autumnalis (Mill.) Chitt., also known as pineapple lily, is a member of the Asparagaceae and native to South Africa. Pineapple lily are well suited for production as pot plants, cut flowers, and garden plants. The potential also exists for this species to be used as a medicinal plant. The aim of the study was to assess the effects of the NO donor of sodium nitroprusside (SNP) on morphological features of E. autumnalis seedlings. The plants grown in a greenhouse were drenched four times, at weekly intervals, with SNP solutions of the following concentration: 0, 100, 200, 300, 400, and 500 μM. The study revealed that the application of SNP significantly improved greenness index of leaves, leaf length, and leaf fresh weight, as compared to the control at all levels. This treatment also showed a significant increase in bulb and root fresh weight, root number, and root length. Application of SNP at 200 μM increased the values of the attributes studied to the maximum extent.

GROWTH, FLOWERING AND PHOTOSYNTETIC PIGMENTS OF PELARGONIUM × HORTORUM L.H. BAILEY ‘SURVIVOR HOT PINK’ AND ‘GRAFFITI FIRE’ GROWN IN SUBSTRATES CONTAINING SEWAGE SLUDGE COMPOST

The aim of this study was to assess usability of composts made of sewage sludge and either straw or leaves used as substrates for growing zonal pelargoniums. The study plants ‘Hot Pink’ cv. of Survivor group and ‘Fire’ cv. of Graffiti group were grown in 5 different substrates. The control substrate was high peat (100%) deacidified with chalk and dolomite up to pH 5.8–6.0 and supplemented with 2.5 g·dm-3 of Azofoska multicomponent fertilizer. The other four substrates contained two types of composts: SSRS – sewage sludge, straw (1:1, v/v) and SSL – sewage sludge, leaves (1:1, v/v), mixed with high peat at two different proportions, 1:3 (v/v) and 1:7 (v/v). Chemical composition of the substrates was investigated and they were supplemented with nitrogen and potassium as recommended for pelargoniums. Plant morphological parameters were evaluated during flowering. They included plant height and diameter, number of shoots and leaves, leaf assimilation area and leaf weight. Leaf chlorophyll and carotenoid content was also estimated. Inflorescence related parameters included inflorescence diameter and inflorescence stem length, number of flowers per inflorescence and flower diameter. All inflorescences formed over 10 weeks of flowering were counted. Plant ornamental value was assessed using a five-score bonitation scale. The investigated composts were found to be useful components of the substrates for zonal pelargonium production. Irrespective of the compost share, the tested substrates significantly affected most of the evaluated morphological traits. The substrate containing the compost made of sewage sludge and straw (SSRS) and peat (1:3, v/v) was found the most beneficial for pelargonium foliage, i.e. the number of leaves, their fresh weight and assimilation area. Leaf chlorophyll and carotenoid content in the pelargoniums grown in the substrates containing either dose of SSRS compost did not differ from the control plants. Substrate type did not affect bonitation score of ‘Survivor Hot Pink’ cultivar. The bonitation score of ‘Graffiti Fire’ cultivar was the highest for plants growing in the substrates with either SSRS or SSL compost plus peat in 1:3 ratio (v/v).