Journal of Ornamental Plants
Volume:11 Issue: 1, Winter 2021

This experiment was performed to investigate the effect of Azolla and rice straw mixed compost in peat substitution on Dieffenbachia amoena. Factorial experiment based on a completely randomized design with two factors of nutrient solution in 2 levels (1- without solution, 2- with 130 mg N L-1, 32 mg P L-1 and 117 mg K L-1) and 5 levels of Azolla and rice straw mixed compost (0, 15, 30, 45 and 60 %) was done in 3 replications, with 3 plants per treatment in greenhouse conditions. Azolla and rice straw mixed compost was replaced with peat in the control. Compost was prepared from a volumetric mixture of 50 % Azolla and 50 % rice straw. Azolla and rice straw mixed compost replaced peat in the control treatment. The control bed contained 10 % perlite: 30 % vermiculite: 60 % peat (volume percentage). Growth factors including height, diameter, number of leaves, chlorophyll index, fresh leaf weight, fresh stem weight, leaf dry weight, stem dry weight, leaf area, physical and chemical characteristics of growth medium and nutrients were measured. The results showed that the use of 45 % Azolla and rice straw mixed compost in replacement with peat (with formula 10 % perlite: 30 % vermiculite: 45 % Azolla and rice straw mixed compost: 15 % peat), in addition to improves the growth factors of Dieffenbachia amoena plant, reduces the consumption of peat by up to 75 %.

Drought stress is one of the most important abiotic stresses that seriously reduces the production of ornamental plants such as pot marigold. Proline is one of the active amino acids in the osmotic regulation phenomenon and it has an effective role in reducing cell damage and improving drought tolerance. A pot experiment as factorial arrangement in a completely randomized design with three replications was performed in order to study the effect of foliar application of proline (0, 50 and 100 mg L-1) on some morpho- physiological characteristics of pot marigold under drought stress (normal irrigation, 25, 50 and 75 % field capacity). The results showed that the highest fresh and dry weight of aerial organ, longevity of the flower on the plant, carotenoid and total chlorophyll were observed in normal irrigation+ proline 100 mg L-1. The highest fresh and dry root weight, root length and total antioxidant activity (DPPH) were for 75 % FC + proline 100 mg L-1. The highest plant height and number of flowers were in normal irrigation+ proline 50 mg L-1. The highest proline content was belonged to 25 % FC+ proline 100 mg L-1. In general, the results of this experiment showed that application of proline can partially compensate for the adverse effects of dehydration and on the other hand, despite the fact that the pot marigold plant is always able to survive in drought stress, it is recommended to irrigate 75% FC in order to increase pot marigold performance.

This study aimed to assess the effect of different levels of nitrogen and potassium on tuberose's quantitative characteristics and identification of its associated pathogens in the Khuzestan province of Iran. The experiment was carried out at Safiabad Agricultural Research and Education and Natural Resources Center as a completely randomized factorial design with 3 replications.  Factors included four levels of nitrogen (0, 100, 200 and 300 kg N ha-1) as Urea, three levels of potassium (0, 150 and 300 kg K2O ha-1) as potassium sulfate and a constant level of phosphorous (100 kg p 2O5 ha-1) as super phosphate.  In current study, leaf nitrogen, spike length, leaf length, SPAD readings, leaf area index (LAI), optical depreciation coefficient, disease percentage and absorbed photosynthetically active radiation parameters were measured. The results showed that the effect of nitrogen on leaf length, SPAD readings, optical depreciation coefficient, absorbed photosynthetically active radiation, and disease percentage was significant at 0.05 probability level while on leaf nitrogen, spike length, and LAI was significant at 0.01 probability level. Potassium had no any significant effect on corresponding parameters in this experiment. In addition, the causal agents of necrotic spots on the tips and edges of the leaves and petals were identified as Botrytis sp., Curvularia sp., and Fusarium sp. while the main cause of necrotic spots on the petals was a thrips, which is probably either F.intonsa or F.schultzei species. Overall, the application of 100 kg ha-1 of nitrogen and no application of K2O are the best treatments and recommended for florists (in planting large bulbs).

Attractive and colorful cultivars of cactus have been developed that are mainly propagated by grafting. The aim of this study was to determine histological events during graft union formation in Gymnocalycium cactus influenced by BA (Benzyladenine) application, grafting method and rootstock. The basal end of the scions and the top end of the rootstocks were first dipped into BA solution at concentrations of 0, 100 and 500 mg L-1 for 10 s, before being grafted on Lemaireocereus marginatus and Myrtillocactus geometrizans rootstocks using horizontal or wedge techniques. Longitudinal sections of the graft union were taken weekly to observe the developmental process of graft formation. The rootstocks did not have a significant effect on grafting success and scion growth, while horizontally grafted Gymnocalycium showed better grafting success rate. The grafting rate and scion growth were enhanced by application of BA compared with the control. The best results were obtained from treating the graft cut-surfaces of both scions and rootstocks with 100 mg L-1 BA. Histological observations showed that the graft union process involved development of a thin necrotic layer, callus formation at the graft interface, cambium differentiation and initiation of new vascular elements, developing the new vascular tissue, and connection of scion and rootstock vascular bundles. BA stimulated rapid proliferation of callus between the scion and rootstock as well as differentiation of vascular elements. We suggest the horizontal graft and application of BA (100 mg L-1) on the cut surfaces of both scion and rootstock as an easy and reliable method for successful graft union in Gymnocalycium cactus, which may have potential use in the commercial production of other cactus species as well.

Poinsettia (Euphorbia pulcherrima) is one of the most important ornamental pot plants that form colored bracts in short days. The present research carried out to evaluate the effect of different concentrations of nitrogen in nutrient solution (180, 230, 280 and 330 mg L-1) and culture media composition (peat moss and perlite (2:1 v/v ratio) and cocopeat and perlite (2:1 v/v ratio) on some morphological and physiological indices of poinsettia. The experimental was factorial based on a completely randomized design with eight treatments and three replications. Results showed that the nitrogen concentration of 230 mg L-1 with cocopeat and perlite media increased plant height, canopy diameter and nitrogen content of leaf tissue. The concentration of 230 mg L-1 nitrogen also increased fresh weight of stem and root more than other treatments whereas highest stem dry weight resulted with the concentration of 280 mg L-1 nitrogen and cocopeat and perlite media. Using peat moss and perlite mixture with 330 mg L-1 of nitrogen increased chlorophyll a and bract anthocyanin content. Generally, results showed that the application of 230 and 280 mg L-1 nitrogen and cocopeat and perlite (2:1 v/v ratio) medium mixture improve growth indices and quality properties of poinsettia.

This review deals with two untreated wastewater types, including domestic wastewater (in tourist destinations) and pharmaceutical industry wastewater, to shed light on the efficiency of constructed wetlands (CW). In mountainous areas, it has always been difficult to have a proper sewage treatment and disposal system for which a proper method is proposed in this paper. In CW, toxic materials should be removed from the water for which a surface CW layer is constructed. Ornamental plants (Canna flaccida, Zantedeschia aethiopica,and Canna indica)were used inthis study and they showed usefulness in reducing 80% of BOD (biological oxygen demand) and COD (chemical oxygen demand). Carbamazepine is a pharmaceutical drug that is widely used and pollutes aquatic environments when it is discharged untreated. This problem can be solved by constructing a horizontal subsurface flow wetland in which the vertical subsurface flow in the wetland is considered and the wastewater is then stabilized in ponds. Three different ornamental species were used (Thypha latifolia, Iris sibirica,and Zantedeschia aethiopica) and their performance was explored on parameters like dissolved oxygen, pH, oxidation/redox potential (Eh) whose average mass removal was 62.5 ± 4.5% and 59.0 ± 4.5%, respectively. The results showed the amazing performance of the two former species. The ornamentals used to get the flowers for commercial production included Zantedeschia aethiopica, Strelitzia reginae, Anthurium andraeanum and Agapanthus africanus. After the system was supplied with the target wastewater, Zantedeschia aethiopica grew about 60 flowers and maintained a healthy outlook while other species grew large leaves, and some died due to the harsh environmental conditions. The reviewed data depicts that Canna indica gave great results for the BOD and COD removal with Z. aethiopica having the potential of giving a greater number of flowers while tolerating the weather conditions. However, for carbamazepine, two species that could take up the pollutants were found to be Iris sibirica and Zantedeschia aethiopica.