مجله گل و گیاهان زینتی
سال دوم شماره 2 (پاییز و زمستان 1396)

Plane tree (Platanus orientalis) is one of the most common trees in urban landscape due to its relatively rapid growth and an appropriate crown, thus it is favored by many landscape designers. In the recent years, chlorosis and early twigs dieback has been a serious problem in some parts of Iran and also the world. In these research field observations in some urban areas of Mahallat city was carried out in order to analyse the plant and soil samples of diseased trees. The results were compared with non diseased trees (as control) by T-Test method. Results showed that diseased trees have less nitrogen, phosphorus and boron compared with non diseased trees, which can be related with the drought stress and imbalance of nutrients. Meanwhile it is possible that salt application for melting of winter ices, has led to increased salinity and activity of lime in the soil and consequently has damageedthe trees. Therefore, it is recommended to estabelish suitable bed by optimizing irrigation and avoids soil salinization.

The planthopper, Orosanga japonicus Melichar (Hem.: Ricaniidae) with feeding on plant sap, excreting honeydew and providing the growth of black sooty mould affects the beauty of the spindle plant, Euonymus japonicus. In this research, efficiency of three chemical insecticides, imidacloprid (0.5 ml/L), chlorpyrifos (2 ml/L), cypermethrin (0.5 ml/L) against O. japonicus was compared with a botanical insecticide, palizin® (2.5 ml/L). Each treatment consisted of three replications and 3 m in length of Euonymus plant that number of live leafhoppers on it was counted one day before spraying up to 5 days after spraying. The efficiency of insecticides was calculated according to Henderson and Tilton’s formula. The most effective insecticide in control of O. japonicus was cypermethrin (100% efficiency). After cypermethrin, imidacloprid caused remarkable efficiency (97-100%). The highest efficiency of palizin® and chlorpyrifos was obtained on the first day (93.8%) and on the second day (80.3%) after treatment, respectively. So, palizin® can be effective in control of O. japonicus because of low risk for the environment and may be used instead of hazardous chemical insecticides in control of O. japonicus.

Rose (Rosa hybrida), is one of the most important cut flowers in the world. Due to importance of extending longevity and decreasing bent neck disorder of rose cut flowers, an experiment was carried out in the Ornamental Plants Research Center, Mahallat. Treatments consisted of different concentrations of salicylic acid in four levels (0, 0.25, 0.5, 0.75 mM). Different characters such as: Electrical conductivity, tissue relative humidity, flower quality index, longevity, amount of solution uptake, number of bacterial colonies, activity of PAL enzyme, lignin formation and amount of protein were measured. Results indicated that electrical conductivity, amount of solution uptake, tissue relative humidity in the 14th and 16th day of experiment were significant at 1(%) level and in the 10th day of experiment, nunmber of bacterial colonies, activity of PAL enzymes, lignin formation and amount of protein were significant at 0.1(%) level. Lowest amount of electrical conductivity and highest amount of PAL enzyme activity was attained at 0.25 mM of salicylic acid, whereas the highest amount of solution uptake was observed in 0.75 mM of salicylic acid. The lowest number of bacterial colonies and highest amount of lignin was obtained in 0mM and 0.5 mM of salicylic acid. Highest amount of protein was achieved in cv. Maroussia, while the highest longevity and best flower quality index was related to cv. Black magic. Lower concentration of salicylic acid caused delay in senescence of Rose flower; however, flower longevity was highly affected by species.

Due to the rapid industrialization, urbanization and transport systems, noise pollution has reached to a disturbing level over the past few years. Plants have been suggested as an affordable and natural construction to mitigate outdoor noise pollution in comparison to concrete, metal, plastic and other man-made materials. The goal of noise control is to promote relaxation, satisfaction and well-being in urban residents. Green belts in residential areas are known as one of the most important and effective methods to reduce noise pollution caused by road traffic in urban areas. A row of trees may be an effective technique compared to other barriers in decreasing noise pollution. In recent years, several methods have been used for measuring the effects of landscape elements on noise reduction. The results showed that green elements not only mitigate noise pollution but also play important role in creating attractive scenes for people which may enhance human tolerance for noise pollution. In addition, organization of plants and their aesthetic values may have positive role on noise reduction.

Assessment and considering the aesthetic value of plants, especially native trees in urban parks, will result in economical, beautiful and sustainable landscapes. Selecting plants in landscape won’t be only on the basis of aesthetic value, but a series of factors including; ecological, functional and aesthetic principles leads to appropriate plant selection. In this study, ten native tree species of Kordkuy city were evaluated. Scoring took place during differetnt seasonsaccording to the beauty of the landscape. The result showed that Parrotia persica and Pterocarya fraxinifolia species were very beautiful and very functional for green space. Acer velutinum Boiss, Alnus glutinosa, Quercus, Diospyros spp and Crataegus ambigua were in the second place and Ruscus aculeatus and Ficus carica trees were classified as average. Therefore, according to the results of this research, native trees can be used for the creation and development of urban green spaces in terms of aesthetic properties.

This study was performed to determine the best plant density and planting methods in two varieties of gladiolus White (White Prosperity) and pink (Rose Supreme). The experiment was conducted in Split-Split Plot design with three replications based on Randomized Complete Block design. The results showed that qualitative and quantitative indices in gladiolus cultivars (White Prosperity and Rose Supreme) were the same in different plant density and planting methodsIn other words, the highest plant height, spike length and diameter of floret was recorded in basin method and density of 40 plants per square meter in White Prosperity and Rose Supreme cultivars. The highest number of floret per plant and the plant fresh weight (gr) was observed in the basin method and density of 70 plants per square meter in White Prosperity and Rose Supreme cultivars. In conclusion, the method of planting basin was the best method for increasing quality and quantity indices of gladiolus plants.