No abstract

Water absorbing geocomposite (GC) consisting of SAP, geotextile and internal skeleton is a novel method of superabsorbent polymer (SAP) and fertilizer application. Roots can overgrow the geotextile and thus obtain access to water. The objective of the experiment was to determine the effect of the geocomposite on the growth of container-grown Brunnera macrophylla. The geocomposite was used as a multi-compound fertilizer (Insol ® U) carrier and compared with soluble fertilizer (SF) and controlled-release fertilizer (CRF). The doses of fertilizers were calculated to cover the equal N supply: 0.36 and 0.72 g plant −1. The geocomposite positively influenced the plant traits after 8 and 16 weeks of cultivation. The number of leaves increased by 42% and 60% and the biomass of the above-ground parts of plants increased by 260% and 340% in comparison to plants treated with other fertilizers. The effect of the fertilization rate on plants was weakly pronounced, but a positive influence of a higher dose and the GC combined on all the examined traits of Siberian bugloss plants was detected.

Silicon is an element that significantly reduces the vulnerability of plants to biotic and abiotic stress factors, increases their resistance to pathogens and pests, strengthens tissues and cellular membranes, increases biomass and crops, improves the nutrition state of plants and increases the chlorophyll content. It also influences the formation of morphological traits of plants. The aim of our research was to determine the influence of silicon contained in the Actisil preparation on the growth and blooming of Gazania rigens, Salvia farinacea and Verbena hybrida, which are commonly cultivated in flowerbeds and on balconies. A two-factor experiment consisted of the foliar application of a solution of silicon in the following concentrations: 0 mg dm -3 , 120 mg dm -3 and 240 mg dm -3 . The application was performed 2, 4 and 6 times at one-week intervals. Biometric measurements were carried out at the beginning of the blooming of plants. The laboratory analyses included determinations of P, K, Mg, Ca, Si and the chlorophyll content in leaves. Beneficial influence of silicon on most of the morphological traits of the analysed species was demonstrated. Plants responded the best to two or four treatments with the silicon solution of a concentration of 120 mg dm -3 , with an increase in the values of the analysed morphological traits. The application of silicon did not significantly modify the content of mineral elements in the dry weight of leaves. The application of silicon to Gazania rigens led to an increase in the content of this element in leaves as well as to an elevated chlorophyll content.

Silicon is known as an element stimulating plant immunity and resistance to unfavorable conditions. Additional treatment with silicon may also cause a positive change in plant performance, improving the quality of ornamental plants. In the years 2009-2010, a two-factorial experiment was conducted involving three cultivars of seasonal ornamental plant species: creeping zinnia Sanvitalia speciosa 'Sunbini', vervain Verbena 'Patio Blue', and purslane Portulaca umbraticola 'Duna Red'. The first experimental factor was the concentration of Actisil preparation being an equivalent of 60, 120, and 180 mg Si×dm^-3, applied three times by spraying, the second one was the type of medium: peat substrate and peat substrate with sand. The experiment proved the beneficial effect of fertilization with silicon on plant development of Verbena and the number of shoots of all examined plant species. The higher concentrations of Actisil were applied, the higher number of shoots the plants developed. Plants treated with Actisil also produced a higher number of buds and flowers or inflorescences featuring an increased diameter. Plants cultivated in peat substrate flowered better

Recent research has proved that supplementary application of silicon, involved in plant tolerance against many stress factors, positively influences plant development improving the quality of ornamental plants. A two-factorial experiment involved four cultivars of ornamental plants: Argyranthemum frutescens 'Blazer Rose', Xerochrysum bracteatum 'Gold', Osteospermum ecklonis 'Grande Pink Blush', and Gaura lindheimeri 'Corinas Choice' The first experimental factor was the concentration of Actisil preparation being an equivalent of 60, 120, and 180 mg Si×dm^-3, applied three times by spraying, while the second one was the type of medium: peat substrate and peat substrate with sand. Actisil had a beneficial effect on the number of lateral shoots in all plants. The highest number of buds and inflorescences was determined in Xerochrysum and Osteospermum plants sprayed with 0.3% Actisil, and 0.2% Actisil in case of Argyranthemum and Gaura. The effect of medium type on plant growth depended on plant species. Argyranthemum and Osteospermum plants cultivated in the medium with sand showed inhibited growth, although medium type did not affect the growth of Xerochrysum