Alireza Moshrefi Araghi; Rohangiz Naderi; Mesbah Babalar; mohammad taheri
Abstract
Poinsettia (Euphorbia pulcherrima) is a potted plant, which its colorful bracts appear in short days. In thisexperiment, effect of different ammonium to total nitrogen ratios on quantitative and qualitative traits ofpoinsettia was studied. The experiment was conducted as a complete randomized design ...
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Poinsettia (Euphorbia pulcherrima) is a potted plant, which its colorful bracts appear in short days. In thisexperiment, effect of different ammonium to total nitrogen ratios on quantitative and qualitative traits ofpoinsettia was studied. The experiment was conducted as a complete randomized design with threereplicates. The plants were irrigated with water containing of different ammonium to total nitrogen ratiosof 0, 0.05, 0.1 and 0.16. At the end of experiment, vegetative traits, fresh and dry weight of shoot androot, chlorophyll index and mineral elements concentration were assessed. Overall study results revealedthat quality and quantity characteristics of poinsettia were significantly affected by various ammoniumsto total nitrogen ratios. So that, the maximum bract area and leaf area achieved for the ratio 0.05 meq/land the minimum achieved for the ratio 0.16 meq/l. Bract productions in plants delayed and its longevitydecreased by ratios higher than 0.05 meq/l. In addition, effect of treatments on fresh and dry weight ofbract, leaf, stem, and root and leaf nitrogen level was significant. According to the results, adjustment ofammonium to total nitrogen in the nutrient solution with ratio of 0.05 meq/l likely makes improving in theproduction characteristics of poinsettia.Keywords: ammonium, bract, chlorophyll
Azizollah Khandan-Mirkohi; Farzaneh Kazemi; Mesbah Babalar; Rouhangiz Naderi
Abstract
To evaluate the effect of limited application of nitrogen (N) on the height control of geranium(Pelargonium hortorum) and improving its quality performance, an experiment was conducted based on acomplete randomized block design with three replications in the greenhouse environment through theyears 2011-2012. ...
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To evaluate the effect of limited application of nitrogen (N) on the height control of geranium(Pelargonium hortorum) and improving its quality performance, an experiment was conducted based on acomplete randomized block design with three replications in the greenhouse environment through theyears 2011-2012. Geranium seedlings were cultivated in the pots filled with peat-based substrate (peat, 80vol. percent + sandy loam field soil 20 vol. percent). For the limited application of N, four differentnutrient solutions with the same macro and micro elements, except N levels of 2.5, two, 1.5 and one mMwere applied. The rate of ammonium to nitrate nitrogen for all treatments was kept as 20 to 80 percent.The traits such as plant height, number and length of shoots, number of florescence and number offlowers in the florescence, pedicle length and leaf number, leaf area, chlorophyll, antocianins, fresh anddry weight of shoot and root were measured at the end of the experiment. Limitation of N applicationfrom 2.5 mM to 1.5 mM in the nutrient solution, although reduced the length of shoot, but did not affectnegatively the quality of plants. Farther decreasing of N level to 1 mM, negatively influenced the allquality and quantity parameters of the plant and may not be introduced for production of geranium.