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The effect of inert media and fertilization levels on nutrition status of green house tomato cv. ‘Maeva F₁’ was investigated. Mean microelement content was: 118.5 mg Fe, 51.7 mg Zn, 269.0 mg Mn and 11.43 mg Cu kg⁻¹ of dry mass of the index parts of the tomato (9–10 leaf form the top). No significant effect of rockwool, expanded clay and polyurethane foam on microelement contents was found in the index parts of the greenhouse tomato, except for zinc whose content was significantly higher in the leaves of the plants grown in rockwool and polyurethane foam than in expanded clay. Fertilization levels did not affect significantly the content of iron, manganese and copper in the index parts, except for zinc whose content lowered at higher fertilization level. High tolerance of the tomato plants to zinc and manganese content in feeding solutions was indicated. No phytotoxicity of zinc nor manganese was found at the content of 2.01 mg Zn and 1.78 mg Mn dm⁻³ of water or feeding solution.
In the years 2005–2007, research work on the influence of surface and subsurface drip irrigation on the yield and quality of roots of parsley grown on ridges and on flat ground was carried out. Irrigation water was supplied via drip lines, which in subsurface irrigation were placed at a depth of 50 mm below the surface of the ridges, along the centreline between two rows of plants. In the case of surface irrigation, the drip lines were placed on the surface of the ridges between two rows of plants. Irrigation started when soil water potential was between -30 and -40 kPa. Nitrogen fertilizers (100 kg⋅ha-1) were applied in two doses. The first dose was applied pre-plant, while the second one was delivered by fertigation. In the control treatment without irrigation, the second dose of nitrogen was applied by broadcasting. Both surface and subsurface irrigation used in the cultivation on ridges and on flat ground had a significant effect on the marketable yield of parsley roots. However, no significant differences in the yield between surface and subsurface drip irrigation were found. The yield of non-marketable parsley roots in flat cultivation was twice as high as that in ridge cultivation. Parsley plants cultivated on ridges produced significantly longer, better-shaped storage roots compared to those cultivated on flat ground. Surface and subsurface drip irrigation significantly decreased the total N and K content in parsley roots.
The content of total iron, cuprum and boron in leaves of four chrysanthemum cultivars was studied in 12 growth cycles starting on the second day of each month throughout the year, from January to December. From the moment of potting, the plants were treated with a short day. In periods of naturally long days, the day was shortened to 10.5 hours using a black-out cover. No supplementary light was used. The time of culture associated with real insolation had a significant influence on micronutrients content. Maximum contents of cuprum and boron were recorded in the leaves of chrysanthemums grown in periods of light deficit. The reverse regularity in case of iron was observed.
Vegetation studies were conducted from 2002 to 2004, in two leading farms, located near Poznan where have obtained optimum anthurium (Anthurium cultorum Birdsey) yielding. Plants were grown in expanded clay with the application of fertigation with a standard nutrient solution (in mg·dm⁻³): N-NH₄<14.0, N-NO₃ 105.0, P 31.0, K 176.0, Ca 60.0, Mg 24.0, S-SO₄ 48.0, Fe 0.840, Mn 0.160, Zn 0.200, B 0.220, Cu 0.032, Mo 0.048, pH 5.5 – 5.7, EC 1.5 – 1.8 mS·cm⁻¹. Significant changes of macroelement contents were found in drainage water in comparison to nutrient solution. The most decreased contents (in %) of macroelements were found for phosphorus (51.2), potassium (26.7) and nitrogen (15.4). The EC value showed a downward trend of about 9.5%. Nutrients which concentration increased in drainage water were (in %): calcium (27.9), sulphur (14.3) and magnesium (5.5). The knowledge of variations of nutrient concentrations in drainage waters is the basis for the practical application of closed fertilization systems with the recirculation of nutrient solution.
Effects of growing media and concentration of nutrient solution on growth, flowering, evapotranspiration and macroelement content of media and leaves of Tymophylla tenuiloba were evaluated under ebb-and-flow conditions. Two media: peat and peat + perlite (3: l, v/v), and four concentrations of nutrient solution: 1.0, 1.5, 2.0, 2.5 mS cml were applied. High quality plants were produced in both media and all concentration of nutrient solution. The lowest evapotranspiration was measured at the highest concentration of nutrient solution. N concentration of leaves was high in all treatments. Concentrations of K, Ca, and Mg decreased with increasing concentration of nutrient solution. Opposite was found for P. At the end of cultivation the lowest pH was measured in the upper layer of growing media. The highest total soluble salt level was measured in the upper layers. Upper layers accumulated more N-N03, P, Ca, and Mg. Mineral element eon tent of both media was high in all concentrations of nutrient solution. Low concentration of nutrient solution at 1.0 mS cm-1 is recommended, although Tymophylla tenuiloba can be also cultivated at higher concentrations of nutrient solution up to 2.5mS cm-l, if placed on the same bench with other bedding plants requiring more nutrients.
In order to achieve a high yield and quality of apple fruit, more effective ways of fertilization are required in the modern, high density apple orchards. The objective of this research was to determine the efficiency (partial nutrient balance, PNB) of different methods (foliar and fertrigation) and forms (chelates and salts) of microelements application in relation to the levels of N fertilization in apple orchard cultivar (‘Golden Delicious’). The combined effects of these fertilizers on the number of apple fruits per tree and on the yield per tree were also studied. Foliar application of Mn, Zn and Fe had significantly higher partial nutrient balance values compared to the soil application in both years of the experiment. However, most of the PNB values were below 10% indicating relatively low efficiency of the applied fertilizers with microelements.
The aim of the study has been to assess the efficiency of choline-stabilized orthosilic acid (ch-OSA; bioavailabile form of silicon) application under increasing intensity of manganese stress on the chemical composition of plants and yielding of tomato (Lycopersicon esculentum Mill. cv. Alboney F1 and cv. Emotion F1). Plants were grown in rockwool with the application of a nutrient solution of the following chemical composition (mg dm-3): N-NH4 2.2, N-NO3 230, P 50, K 430, Ca 145, Mg 65, Cl 35, S-SO4 120, Fe 2.48, Zn 0.50, Cu 0.07; pH 5.50, EC 3.00 mS cm-1. The following manganese levels in the nutrient solution were tested (mg dm-3): 9.6 and 19.2. The effect of ch-OSA application (at a concentration of Si equal 0.3 mg dm-3 of the nutrient solution) was investigated at both Mn-levels. The ch-OSA application alleviated Mn toxicity by increasing the biomass production in the Mn-low variant (+ 8.2% for Alboney F1 and 16.8% for Emotion F1, the differences being significant for Emotion F1), whereas the ch-OSA application in the Mn-high variant did not influence the plant yielding. All the factors affected the plant nutrient status and the chemical composition of tomato fruits. The chemical composition of leaves depended on (means of all the studied combinations): Mn (K, Na) and ch-OSA nutrition (N, Mg, Na), cultivar (for P, K, Ca, Na), but in the case of fruits significant differences were found between Mn (N, P, Ca, Mg) and ch-OSA nutrition (N, Mg, Na) and cultivar (N, P). In both Mn-levels, visual symptoms of manganese toxicity appeared on plants – in the Mn-high variant, they were observed after 4 weeks, while in the case of the Mn-low variant - after 10 weeks of exposure to strong Mn-stress. Treatment with ch-OSA at both of the studied Mn levels did not prevent the development of visual toxicity symptoms on the plants.
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